D04D - INSTALLATION GUIDE - SANDING AND FINISHING
D04D-1 Basics of hardwood finishing
D04D-2 Site or pre-finished flooring?
D04D-3 Selecting a finish
D04D-4 Colourants
D04D-5 Wood fillers
D04D-6 Sealers
D04D-7 Glazes
D04D-8 Toners
D04D-9 Finishes
D04D-10 Factory or pre-finishing
D04D-11 Site finishing - general
D04D-12 Site sanding
D04D-13 Site sanding / refinishing of existing hardwood flooring
D04D-14 Final preparation for site finishing
D04D-15 Application of sealers
D04D-16 Application of penetrating sealers with stain
D04D-17 Application of pigmented wiping stains
D04D-18 Application of other stains
D04D-19 Application of surface finishes
D04D-20 Application of decorative borders and patterns
D04D-21 Finishing hardwood sports flooring
D04D-22 Refinishing
D04D-2 Site or pre-finished flooring?
D04D-3 Selecting a finish
D04D-4 Colourants
D04D-5 Wood fillers
D04D-6 Sealers
D04D-7 Glazes
D04D-8 Toners
D04D-9 Finishes
D04D-10 Factory or pre-finishing
D04D-11 Site finishing - general
D04D-12 Site sanding
D04D-13 Site sanding / refinishing of existing hardwood flooring
D04D-14 Final preparation for site finishing
D04D-15 Application of sealers
D04D-16 Application of penetrating sealers with stain
D04D-17 Application of pigmented wiping stains
D04D-18 Application of other stains
D04D-19 Application of surface finishes
D04D-20 Application of decorative borders and patterns
D04D-21 Finishing hardwood sports flooring
D04D-22 Refinishing
Preface:
This reference guide covers both factory and site finishing of hardwood flooring. The information given is a guide only and cannot fully cover all aspects of finishing hardwood flooring. Specifiers and/or persons selecting finishes for such products should verify all facts relative to finish types and availability with the product manufacturer / supplier.
1 • BASICS OF HARDWOOD FINISHING
.01 Hardwood flooring is finished not only to enhance or alter its natural beauty (grain and colour) but also to protect it from damage, wear, dirt, oxidation and from the rapid exchange / absorption of moisture. As a flooring surface hardwood flooring will be subject to wear depending on the amount of traffic it is subject to. Any finish will play an important part in protecting and maintaining the appearance and durability of the flooring.
.02 Whether a finish is site or factory applied it is expected that it will eventually wear off and need to be recoated or completely replaced. With proper care and maintenance the life expectancy of such finishes can be greatly extended. Some finishes are more durable than others. A poor quality or poorly applied finish will allow a wood's natural beauty to deteriorate and create an unneeded maintenance problem. The selection of an appropriate finish and its proper application must be done with due care based on sound knowledge and experience.
.03 Irrespective of the type of flooring and finish selected, there are some things that should not be expected of hardwood flooring and finishing:
This reference guide covers both factory and site finishing of hardwood flooring. The information given is a guide only and cannot fully cover all aspects of finishing hardwood flooring. Specifiers and/or persons selecting finishes for such products should verify all facts relative to finish types and availability with the product manufacturer / supplier.
1 • BASICS OF HARDWOOD FINISHING
.01 Hardwood flooring is finished not only to enhance or alter its natural beauty (grain and colour) but also to protect it from damage, wear, dirt, oxidation and from the rapid exchange / absorption of moisture. As a flooring surface hardwood flooring will be subject to wear depending on the amount of traffic it is subject to. Any finish will play an important part in protecting and maintaining the appearance and durability of the flooring.
.02 Whether a finish is site or factory applied it is expected that it will eventually wear off and need to be recoated or completely replaced. With proper care and maintenance the life expectancy of such finishes can be greatly extended. Some finishes are more durable than others. A poor quality or poorly applied finish will allow a wood's natural beauty to deteriorate and create an unneeded maintenance problem. The selection of an appropriate finish and its proper application must be done with due care based on sound knowledge and experience.
.03 Irrespective of the type of flooring and finish selected, there are some things that should not be expected of hardwood flooring and finishing:
- A perfectly flat "table top" or "mirror-like" finish is not achievable. A smooth surface to the eye is achievable. However depending on the cut (plain or quarter sawn) and the fact that each resulting piece of flooring will sand differently depending on its grain (resulting in raised grain) and differential moisture absorption on either side due to humidity or substrate conditions it will make it virtually impossible to provide or maintain a completely flat surface.
- A monochromatic (single colour) finish is not possible as wood is a natural not a man made product that varies from piece to piece. Each milled piece will have its own unique grain pattern and colour variation consistent within the grade and species selected. If a monochromatic finish is required then choose another flooring material rather than hardwood flooring.
- Any touch-ups required due to damage may not be consistent with or match the applied finish, particularly factory applied finishes. A touch-up kit of stains and coatings from the same batch used on the material supplied complete with instructions should be provided by the applicator or manufacturer.
- A dust free site finish is virtually impossible. Since finishing on site is never conducted in a "clean room" environment, it is not possible to achieve a totally dust free surface. Some dust may fall onto a freshly applied finish.
- An impact resistant or dent free floor is not possible. In spite of the term "hardwood", even the hardest wood flooring species, such as Brazilian Cherry, Jarrah, or Wenge, will still dent, albeit less than Oak flooring. High heel traffic (especially damaged heels) will dent and mar hardwood flooring and any finish applied will not prevent this from happening.
- Depending on the colour, species, construction, and installation method used, a gap / crack free floor is virtually impossible, particularly with glue-down flooring (this occurs less with engineered flooring). Although new strip, plank, or parquet flooring will be laid with tight joints, it will, as a natural product, absorb and release moisture overtime in its environment. This natural process will cause the flooring to expand and contract from season to season with the changes in humidity and temperature. This will result in some cracks between some of the thousands of pieces of hardwood in the floor assembly. It should also be noted that some light stain colours, such as white, will likely show more gaps / cracks than dark stains.
- Not all surfaces can be finished. Installation of site or pre-finished flooring will require cutting, fitting, and at least some touch-up finishing. Some of the flooring will be beyond reach of close inspection when an installation is complete.
2 • SITE OR PRE-FINISHED FLOORING?
.01 There are many finishing systems produced by a variety of manufacturers for both pre-finished and site-finishing hardwood flooring, each with their own recommendations and guidelines for application (site applied) and for maintenenance. As a result, costs of finishing systems vary greatly with the higher performing finishes usually being more costly than lower performing finishes.
.02 The choice of pre-finished material (i.e. factory finished) or site-finished material (i.e. finished after installation) requires careful consideration. There are a number of factors that should be considered when choosing one or the other.
.01 There are many finishing systems produced by a variety of manufacturers for both pre-finished and site-finishing hardwood flooring, each with their own recommendations and guidelines for application (site applied) and for maintenenance. As a result, costs of finishing systems vary greatly with the higher performing finishes usually being more costly than lower performing finishes.
.02 The choice of pre-finished material (i.e. factory finished) or site-finished material (i.e. finished after installation) requires careful consideration. There are a number of factors that should be considered when choosing one or the other.
Site Finished
.03 Advantage of site finishing hardwood floors: Site sanding and finishing hardwood flooring creates a seamless, smooth look to the finished product. Bevels or (V grooves) are not required to compensate for unevenness between planks. This results in a smooth even surface throughout the floor installation. Custom stain colors can be chosen. Finish sheen levels can be chosen.
Prefinished
.04 Pre-finishing hardwood flooring: Most pre-finished flooring has an eased or beveled edge used to compensate for any unevenness between planks. Pre-finished flooring planks show little to no trace of factory sanding and finishing. Factory applied finishes are harder than air drying site applied finishes. Many factory finished hardwood floors are supplied with additives such as Aluminum Oxide or Ceramic particles in one or more of the multiple, factory applied finishes layers. These additives increase the durability of the whole finish system.
Pre-finished hardwood flooring wear warranties are very detailed and require specific maintenance procedures be carefully followed. These include descriptions of acceptable maintenance, regularity of cleaning and preventative maintenance, Each manufacturer should provide detailed maintenance instructions, warranty details and installation guidelines with each product. Such documents can usually be downloaded from the manufacturers website. In all cases such documents should be fully reviewed prior to purchasing and installing any product.
Pre-finished hardwood flooring wear warranties are very detailed and require specific maintenance procedures be carefully followed. These include descriptions of acceptable maintenance, regularity of cleaning and preventative maintenance, Each manufacturer should provide detailed maintenance instructions, warranty details and installation guidelines with each product. Such documents can usually be downloaded from the manufacturers website. In all cases such documents should be fully reviewed prior to purchasing and installing any product.
3 • SELECTING A FINISH
There are a number of other factors that must be considered when selecting a finish system.
.01 Number of Coats
There are a number of other factors that must be considered when selecting a finish system.
.01 Number of Coats
- Thin coatings do not protect or moisture-proof the wooden surface and a thin, light coat of finish will often leave the surface dry with completely open pores.
- The least expensive oil finish requires eight coats to equal two coats of a catalyzed urethane, yet the oil will not protect the surface against water or chemicals.
- Top coat costs vary greatly.
- Low-cost finishes may have only 30 percent solids and 70 percent solvent while more expensive finishes might have 70 percent solids, 10 percent catalyst and 20 percent solvent.
- Unnecessary costs can be added to a project by over-specifying a finish. In millwork, for example, crown moldings at the ceiling line do not have to have the same level or quality of finish as that required for handrails.
.02 Wear Resistance- The wear resistance of a finish depends on the coating's strength, which is based on its molecular makeup, its solids content, and the final dry film total thickness of the applied finish. Most wood finishes are made of complex mixes of resins, ranging from simple long grain oils to lacquers, varnishes, vinyls, urethanes, and polyesters with each having their own characteristics in regard to wear and durability.
.03 Chemical Resistance- Some cleaners (including most household cleaners) contain strong chemicals that may harm an applied finish. The relative resistance to these chemicals is an important issue when selecting an appropriate finish system.
.04 Reparability- Scratches in the top clear layers of a finish are fairly easily repaired with any of the finishing systems. Scratches that penetrate the stain will require the addition of a colourant and a clear coat. Scratches that go deeply into the wood will have to have a filler or binder added to build up the damaged area before the application of a new top layer of finish.
- Repairs made with soft-coloured putty will look fine the first day, but given a few weeks and viewed from the side they may show small smudges of oily residue and will attract dirt or dust.
.05 Adhesion- Adhesion is a finish's ability to stick to the flooring's surface. Adhesion is very important because a nick or dent can break the bond between the wood and finish. At that point the finish will become translucent and flake off. In some cases stains or solvents can interfere with the process of adhesion.
- Almost all touch-up colour should be a similar coating to the finish surrounding it. A competent touch-up or repair requires a good eye for colour and its surface effect, gloss, and grain character. Almost all finish is repairable, but high gloss finishes are the hardest to repair.
.06 Clarity
- Some finishes are clearer than others. Conversion varnishes and water-borne applications may appear milky when small bubbles are entrapped in the finish. This "micro-foam" will also show up as a consistently milky area when applied over a dark stain.
- Many finishes have an amber colour, and thus appear to be less clear. The typical term used in the profession when looking for a clear finish is "water white." However, on wood such as red oak, or white oak, a yellowish finish may enhance the character of the wood and be aesthetically pleasing. When trying to attain a clear dark colour, the best results come from a finish that has a high clarity.
.07 Elasticity and Hardness
.08 Application and Thickness
- Wood is an elastic natural material which moves constantly with changes in humidity and temperature. Finishes that are too brittle or inelastic, or become so over time, are not recommended for wood.
.08 Application and Thickness
- In addition to the type of finish the performance of a finish depends on the applied dry film thickness as well as the care and maintenance of the finish.
- The required number of finish coats depends on the material manufacturer's recommendations for the type of wood and performance level required. The total dry film thickness of the applied coating system must meet these requirements. Given the varying solids content of finishes, a suggested rule of thumb for the number of coats required should be based on a combined total solids content of 100. This means that if the solids content of a finish is 50% then a total of two coats would be required.
The skill of the applicator, the method of application (brush, roller, mop, or spray) and the application / spread rate are all important. Materials must be installed by skilled applicators, using appropriate tools and methods, and in strict conformance with the manufacturer's spread rates.
4 • COLOURANTS
Colourants are dye or stain materials used to enhance or change the colour of hardwood flooring. They are applied to the wood, allowed to soak in, and the excess is then wiped off, and the wood then dried. Some colourants may seal the surface while some may not. Where the latter is the case the wood must be sealed. Some colourants may present a mottled appearance as spring wood absorbs more colour than winter growth wood. The use of any dye or stain therefore must be done in strict accordance with the material manufacturers recommendations using flooring material samples to ensure compatibility of materials and the desired final finish appearance.
Colourants can be broken into two large groups:
.01 Dyes
.02 Stains
Colourants are dye or stain materials used to enhance or change the colour of hardwood flooring. They are applied to the wood, allowed to soak in, and the excess is then wiped off, and the wood then dried. Some colourants may seal the surface while some may not. Where the latter is the case the wood must be sealed. Some colourants may present a mottled appearance as spring wood absorbs more colour than winter growth wood. The use of any dye or stain therefore must be done in strict accordance with the material manufacturers recommendations using flooring material samples to ensure compatibility of materials and the desired final finish appearance.
Colourants can be broken into two large groups:
.01 Dyes
- Dyes are a solution of colourants in mineral spirits, oil, alcohol or water. Modern woodworking dyes are very similar to those used for dyeing cloth, paper or leather. Dyes change the hue of the wood without hiding its figure or rendering the surface unclear or muddy. In addition, dyes penetrate both the soft and hard grain, and often enhance or "bring out the grain."
- The molecular size of the dye particles is much smaller than that of mineral particles in stains, and thus dyes appear more transparent. In addition, dyes bind to the wood because of their chemical molecular structure and no additional binder is required. With water-based dyes, as the water evaporates, the wood is left with only the colour in its surface.
- There are four main types of dyes: water-based, alcohol-based, oil-based, and solvent-based. Each has a particular use in the colouring process. With Maple or Birds-eye Maple for instance it may be found that water-soluble dyes penetrate more evenly across the whole surface. On a more oily wood, oil, or solvent-based dyes may penetrate better.
- Oil and solvent-based dyes may be added to pigment stains to form a combined stain and dye. This process may be able to yield the same colour with only one operation.
- Dyes are less light-fast than pigmented stains and in renovation work this can be used to an advantage.
.02 Stains
- Produced from a variety of synthetic and organic mineral sources, stains are dispersions of particles of pigment within an oil or solvent base. The pigments are ground into fine particles and come in a powdered form that may be added to other stains to increase colour and density.
- The depth of the stain and its opaqueness are directly related to the pigment's solubility, as well as the size, and density of particles in the solution.
- Stains may be sprayed, brushed, or wiped onto the surface. The depth of penetration and final colour are determined by the length of time the stain is allowed to remain on the surface and how hard the stain is wiped off.
- In very dark colours, it is difficult to reach the saturation of colour without also covering the grain. For this reason, many projects are coloured with a dye and then stained to produce a clear but dark colour.
- Pigmented stains will fill the grain and leave the wood surface with less colourant, whereas dyes will stain the grain and the areas between the grain approximately the same colour.
- Oil-based stains are convenient for large areas if site finishing is used as they dry more slowly, giving the finisher more time to wipe off the excess stain.
- For future re-finishing, it is essential to know the brand names and colour of the stain and other finishing products used, or if the floors were pre-finished at the flooring manufacturing plant.
- Not a dye or stain, bleaches specially formulated for wood flooring, reduce variations in colour without obscuring the grain pattern. White stain is sometimes applied after bleaching. Any stain used after bleaching must be compatible with bleach. The use of bleach also tends to soften the wood and drying time is critical.
- Factory bleaching is also available from some manufacturers for pre-finished hardwood flooring.
5 • WOOD FILLERS
.01 Woods with open grain structure such as oak and ash have very large pores. In some cases it may be desirable to fill the pores to allow the surface to appear smoother or the pores to appear lighter. Oil-based fillers may be mixed with oil-based stains to even the wood's colour and fill in one step.
.02 Fillers are applied in a heavy film or paste form either by spraying or brushing, and the excess is wiped off with rags, scrapers, or burlap, flush with the top of the wood surface.
6 • SEALERS
.01 All finishes require a sealer to "seal" the wood surface thus reducing the absorption of succeeding coats allowing them to build up.
.02 Sealers are also used to lock in the colourant or stain and protect the grain. Sealers start the filling process and provide a sandable coating. In many cases, the sealer is filled with particles that make the surface easier to sand but may also inhibit clarity.
.03 Sealer Types: There are two basic types
.05 Other Types of Sealers: A number of sealers were used originally but due to advances in technology, environmental concerns (VOC's and off-gassing), and in some cases their flammability they are no longer used or recommended. These include the following:
.01 All finishes require a sealer to "seal" the wood surface thus reducing the absorption of succeeding coats allowing them to build up.
.02 Sealers are also used to lock in the colourant or stain and protect the grain. Sealers start the filling process and provide a sandable coating. In many cases, the sealer is filled with particles that make the surface easier to sand but may also inhibit clarity.
.03 Sealer Types: There are two basic types
- Penetrating Sealer and Wax: Clear; normal or fast drying sealer for natural finish which soaks into wood pores and hardens to seal the floor against dirt and stains. Two coat application is recommended, followed by hardwood floor wax and buffing.
- Penetrating Sealer with Stain: If other than a natural finish is desired staining must be a first step in the finishing process. Stains are available in a number of wood tones and several colours. A pigmented wiping stain (a penetrating oil-resin vehicle to which pigments have been added) is normally used. The pigment collects in the open pores of the wood and accentuates the grain pattern. Stain is applied followed by clear penetrating sealer and wax.
- Oil Based Carriers: Oil modified sealers are similar to a regular topcoat finish with a 40 to 50% solids content except they have a much lower solids content (30 to 35%). Because of the higher mineral spirit content these sealers penetrates the wood more. As mineral spirits dry slowly there are fast drying oil-modified sealers with faster drying solvent or additives. The use of such sealers may now be limited due to increasing environmental concerns (VOC's and off-gassing).
- Water Based Carriers: water based sealers which break down into two types: acrylic and acrylic / urethane types each available as a single-component product or a two-component product requiring a catalyst or cross-linker.
.05 Other Types of Sealers: A number of sealers were used originally but due to advances in technology, environmental concerns (VOC's and off-gassing), and in some cases their flammability they are no longer used or recommended. These include the following:
- Lacquer and Shellac: Alcohol based and extremely flammable. These still may be used in some areas because of their fast drying times: 1 hour for shellac and 15 minutes for lacquer.
- Linseed and Tung Oil: These products form the basis for most oil-based stains but are rarely used alone today as sealers.
7 • GLAZES
.01 Glazes are transparent or semi-transparent stains that are applied after the sealer coat. In some cases, a transparent alcohol dye may be applied as a glaze as well. Glazes are often used to even out a light and dark area after the staining and sealing process.
.02 It is only after the sealer has been applied and sanded that the true colour of the wood can be seen. This is also typically the time when touch-up of glue marks and unevenness of colour can be corrected.
.01 Glazes are transparent or semi-transparent stains that are applied after the sealer coat. In some cases, a transparent alcohol dye may be applied as a glaze as well. Glazes are often used to even out a light and dark area after the staining and sealing process.
.02 It is only after the sealer has been applied and sanded that the true colour of the wood can be seen. This is also typically the time when touch-up of glue marks and unevenness of colour can be corrected.
8 • TONERS
.01 Toners are tinted applications of sealers or top coats which are used to build up a colour.
.02 Toners tend to cover the grain because they are essentially pigments suspended in the finish.
.01 Toners are tinted applications of sealers or top coats which are used to build up a colour.
.02 Toners tend to cover the grain because they are essentially pigments suspended in the finish.
9 • FINISHES
.01 A finish is one or more top-coats applied to protect wood from abrasive wear from foot traffic. When such finishes wear out they can be sanded down and re-applied (re-coated). These finishes take many forms:
b. Oil-Modified Urethanes: A solvent-based urethane finish that dries by solvent evaporation in about eight hours and ambers with age. Easy to apply this type was once the most common surface finish but is being replaced due to environmental concerns (VOC compliance).
c. Moisture-Cured Urethanes: A solvent-based polyurethane finish that cures by absorbing minute quantities of moisture from the air, which causes it to dry and harden. Relative humidity is critical to the curing process. This type of finish is harder and more moisture resistant than the other surface finishes and comes in non-yellowing and in ambering types generally available in satin or gloss. These finishes are extremely difficult to apply, have a strong odour and are best left to the professional.
.01 A finish is one or more top-coats applied to protect wood from abrasive wear from foot traffic. When such finishes wear out they can be sanded down and re-applied (re-coated). These finishes take many forms:
- Urethanes: A blend of synthetic resins, plasticizers, and other film-forming ingredients, which produce an extremely durable surface, that is moisture-resistant. Urethanes are available in high gloss, semi-gloss, and matte finishes, and in water-base, oil modified, or moisture curing forms.
b. Oil-Modified Urethanes: A solvent-based urethane finish that dries by solvent evaporation in about eight hours and ambers with age. Easy to apply this type was once the most common surface finish but is being replaced due to environmental concerns (VOC compliance).
c. Moisture-Cured Urethanes: A solvent-based polyurethane finish that cures by absorbing minute quantities of moisture from the air, which causes it to dry and harden. Relative humidity is critical to the curing process. This type of finish is harder and more moisture resistant than the other surface finishes and comes in non-yellowing and in ambering types generally available in satin or gloss. These finishes are extremely difficult to apply, have a strong odour and are best left to the professional.
- Water-Based Urethanes: A water-borne type urethane finish available in single or two component form (the latter requiring a catalyst or cross linker) that dries by water evaporation in about two to three hours. These finishes are clear and non-yellowing and have a milder odour than oil-modified finishes.
- Oil-Modified Urethanes: A solvent-based urethane finish that dries by solvent evaporation in about eight hours and ambers with age. Easy to apply this type was once the most common surface finish but is being replaced due to environmental concerns (VOC compliance).
- Moisture-Cured Urethanes: A solvent-based polyurethane finish that cures by absorbing minute quantities of moisture from the air, which causes it to dry and harden. Relative humidity is critical to the curing process. This type of finish is harder and more moisture resistant than the other surface finishes and comes in non-yellowing and in ambering types generally available in satin or gloss. These finishes are extremely difficult to apply, have a strong odour and are best left to the professional.
- Conversion Varnish or Swedish Finish: A clear, fast drying, moisture resistant, non-yellowing durable acid-curing urea formaldehyde floor finish that is generally harder than polyurethanes. The type of undercoat, working time, number of coats, and other factors are all critical and make application difficult. This finish should be applied ONLY by highly skilled applicators.
- Water-Based Urethanes: A water-borne type urethane finish available in single or two component form (the latter requiring a catalyst or cross linker) that dries by water evaporation in about two to three hours. These finishes are clear and non-yellowing and have a milder odour than oil-modified finishes.
10 • FACTORY OR PRE-FINISHING
.01 As the name implies factory finished hardwood flooring is sanded and finished in the manufacturer's plant using various finishes. The types of finishes available and their suitability must be reviewed by the Design authority or Owner prior to selection.
.02 Factory finishing offers some advantages: Refer also to item 2 above.
- Finishing: Site finishing hardwood entails three steps – sanding, staining / sealing, and finish coating. Factory finished hardwood may go through as little as four to as many as thirteen steps during finishing that may include additional sanding and extra finish coats which add richness and depth to the material. As in site finishing, factory finishing may also use bleaches, stains, and sealers.
- Controlled Environment: All factory finishes including the use of bleaches, stains, and sealers are applied in a controlled environment in accordance with the manufacturer's specifications and should result in a consistent finish. In addition manufacturers don't have to contend with the effects of other building trades working nearby and the effects of dust, traffic, temperature, and humidity.
- The Right Tools: Pre-finishing operations work with low-pressure, high-volume spray guns and spray booths, so uniformly good appearance from piece to piece comes much more easily.
- Cost and Labour: Pre-finished hardwoods can cost more than unfinished products, however, savings may be realized in both installation and finishing. Finishing hardwood flooring to factory standards in the field can tie up a work site for a number of days. In addition, a crew of finishers and extensive site preparation is required. As well adjacent work could jeopardize the quality of the finish and may have to stop, adding time to the construction schedule. With pre-finished products, site preparation is simpler, and other trades can continue to work. A lone qualified individual can complete touch-up in a day or two.
- Sheen levels are determined by the amount of light reflecting off the finish. Each manufacturer can use different application procedures that can affect sheen levels. There are different sheen level options (listed below). Products supplied with lower sheen levels such as Satin or Matte, can help disguise normal wear and tear hence most manufacturer's use lower reflective sheen levels on their products. The glossier (shinier) the finish, the more natural wear and tear is noticed. For this reason, very few manufactures will produce pre-finished hardwood flooring in a gloss finish.
- Gloss - Highly reflective (site applied). Likely to show wear and tear sooner than a finish sheen that reflects light less such as Satin or Matte.
- Semi-Gloss
- Satin
- Matte - Lower light reflection
.03 Factory Finishes: A variety of proprietary finishes specially formulated for factory finishing of hardwood flooring are available from most hardwood flooring manufacturers. These are non-yellowing ultra-violet (UV) resistant and durable coatings requiring no waxing that are applied in numerous layers, or baked into the wood. The types available may include:
- Baked / Pigmented Finish: Tung oil filler and pigmented finish applied and baked into wood followed by carnauba wax which is melted and applied to the wood and baked. The final flooring is then brushed and buffed to a satin finish.
- Polyurethane Finish: A surface finish of four or more coats of UV resistant urethane to manufacturer's standard, available in matte, semi-gloss or gloss finish.
- Swedish Finish: A clear, fast drying, non-yellowing resin based extremely durable surface finish that is available in different sheens.
- Polyurethane Finish with Aluminum Oxide or Ceramic Granules: A finish that contains aluminum oxide or ceramic granules for added wear resistance. These grit materials were initially applied in the final coats of finish but created a problem if the floor ever needed to be sanded and re-coated at a later date. Most manufacturers now apply one or two coats of an anti-scratch surface coat that contains aluminum oxide or ceramic granules over the finish coat. This finish can be cleaned and re-coated to take care of minor surface scratches and worn appearances without having to remove all the finish down to bare wood.
- Special Finishes: Other factory finishes may be available. The designer or Owner must verify the types and suitability with flooring manufacturers.
.04 Moldings and accessories used with factory finished flooring may be supplied sanded and finished or be unfinished with finishing to be done on site to match the floor finish.
.05 Touch-up and Repair of Prefinished Hardwood: Maintaining consistency of finish across a whole installation with pre-finished hardwood may be a concern especially where cutting and mitering or damage exposes fresh wood. Some factory finishes are difficult to match, and touch-ups are tricky if there's damage on a busy job-site. Finish matching is easier, however, if a touch-up kit of stains and coatings from the same batch used on the material supplied complete with instructions is provided by the manufacturer. Any such touch-up repairs must conform to the material manufacturer's written requirements.
.05 Touch-up and Repair of Prefinished Hardwood: Maintaining consistency of finish across a whole installation with pre-finished hardwood may be a concern especially where cutting and mitering or damage exposes fresh wood. Some factory finishes are difficult to match, and touch-ups are tricky if there's damage on a busy job-site. Finish matching is easier, however, if a touch-up kit of stains and coatings from the same batch used on the material supplied complete with instructions is provided by the manufacturer. Any such touch-up repairs must conform to the material manufacturer's written requirements.
11 • SITE FINISHING - GENERAL
Note: The following is general information only. Site finishing requirements vary with the type of hardwood flooring and finish selected. Refer to finish manufacturer's product instructions and those of the equipment being used.
Note: The quality of any site finish depends on the species of wood, the type of finish materials and equipment used, and on the experience and skill level of the individual performing the finishing work.
.01 After unfinished hardwood flooring has been installed it must be carefully inspected. Any loose boards must be tightened by face nailing using the correct flooring cleats or nails, preferably into joists, and any damaged or defective flooring boards removed and replaced. In addition, any protruding nail heads or nails not driven down below the wood's surface must be pulled out or counter-sunk using a nail set (sanding exposed nails can produce sparks creating a fire hazard in the sander dust bag). Any missed cracks and nail holes must be spot filled using a putty knife with a sparingly applied commercial flooring filler. When dry, these shall be hand sanded with fine sandpaper of the same grit to be used in the final sanding.
Note: Check with finish manufacturer or supplier to make sure fillers are compatible with finish materials to be applied.
.02 All site finishing of flooring should begin one to three weeks after installation is complete and the flooring has become acclimatized to its environment and after the wood surfaces have been properly prepared (e.g., sanded). Longer periods of exposure to job site conditions before site finishing can result in future problems.
Note: Check with finish manufacturer or supplier to make sure fillers are compatible with finish materials to be applied.
.02 All site finishing of flooring should begin one to three weeks after installation is complete and the flooring has become acclimatized to its environment and after the wood surfaces have been properly prepared (e.g., sanded). Longer periods of exposure to job site conditions before site finishing can result in future problems.
.03 Prior to any sanding operations, the area, including ventilation ducts, shall be suitably sealed off and all surfaces shall be suitably masked to prevent dust from contaminating surfaces and to prevent dust from entering into adjacent areas.
.04 Site finishing of moldings and accessories used with site finished hardwood flooring must also be sanded and finished on site to match the selected floor finish.
.04 Site finishing of moldings and accessories used with site finished hardwood flooring must also be sanded and finished on site to match the selected floor finish.
12 • SITE SANDING
.01 Immediately before sanding all floor surfaces must be swept clean or vacuumed and inspected for any protruding nail heads and loose boards, and any damaged or defective boards must be remedied or replaced.
.01 Immediately before sanding all floor surfaces must be swept clean or vacuumed and inspected for any protruding nail heads and loose boards, and any damaged or defective boards must be remedied or replaced.
.02 A sander, an edger, and a floor polisher with a disc attachment for holding sand paper or screen discs should be used to sand floor surfaces to achieve the finish desired.
Note: The type of sanding equipment used (e.g. drum, oscillating, or orbital type sanders and edgers), the grit of paper, and the number of cuts or passes required to achieve the level and quality of sanded finish required, depends entirely on the experience and skill level of the individual doing the sanding.
.03 Generally speaking, all hardwood floor surfaces are sanded initially with a course grit sand paper, followed by a medium grit sand paper, and then completed by using the same procedure with a fine grit sand paper. The direction of the various sand paper cuts and other sanding techniques shall be in accordance with material manufacturer recommendations and minimum NFCA / NOFMA requirements.
.04 If an edger is used to blend in the perimeter of the room with the field, a screen disc should be used (on the buffer) over the entire floor, or the edged areas should be hand sanded with the last grit paper used on the drum.
.05 If the floor is to be stained, a slightly heavier grit final abrasive should be used to enable the stain to penetrate more readily. If acceptable to the Owner or authorities having jurisdiction, a light, hit-or-miss application of kerosene before the disc cut will emphasize un-sanded areas and streaks, and reveal the marks likely to show up when finish is applied. The use of this material however may not be acceptable due to WHMIS and/or LEED requirements.
.06 When machine and hand sanding are completed and immediately before the application of any finish, all floor surfaces shall be swept and vacuumed clean using a heavy duty vacuum cleaner. In addition, all dust on windows, sills, doors, door frames, and baseboards shall be wiped up and/or vacuumed.
.07 Any indentations, grease, oil and other wood defects must be removed with multiple grits of sandpaper, scraping, and even sponging and then sanding to enable the stain and finish to be taken into the pores evenly across the whole surface.
.08 Certain closed grain woods such as maple and cherry tend to develop finishing blotches caused by textured grain. No matter how much sanding is used on these areas, they will never disappear. In some instances water popping or special conditioning can reduce such blotching. Refer to item 14.06.
.09 A stain's penetration also depends on the final grit with which the wood was sanded. For instance, the large valleys left by 80 grit sandpaper will absorb much more pigment than will the fine tracks left by 150 grit sandpaper. For this reason it is important to prepare samples with the actual grits and the actual stains and finishes.
.04 If an edger is used to blend in the perimeter of the room with the field, a screen disc should be used (on the buffer) over the entire floor, or the edged areas should be hand sanded with the last grit paper used on the drum.
.05 If the floor is to be stained, a slightly heavier grit final abrasive should be used to enable the stain to penetrate more readily. If acceptable to the Owner or authorities having jurisdiction, a light, hit-or-miss application of kerosene before the disc cut will emphasize un-sanded areas and streaks, and reveal the marks likely to show up when finish is applied. The use of this material however may not be acceptable due to WHMIS and/or LEED requirements.
.06 When machine and hand sanding are completed and immediately before the application of any finish, all floor surfaces shall be swept and vacuumed clean using a heavy duty vacuum cleaner. In addition, all dust on windows, sills, doors, door frames, and baseboards shall be wiped up and/or vacuumed.
.07 Any indentations, grease, oil and other wood defects must be removed with multiple grits of sandpaper, scraping, and even sponging and then sanding to enable the stain and finish to be taken into the pores evenly across the whole surface.
.08 Certain closed grain woods such as maple and cherry tend to develop finishing blotches caused by textured grain. No matter how much sanding is used on these areas, they will never disappear. In some instances water popping or special conditioning can reduce such blotching. Refer to item 14.06.
.09 A stain's penetration also depends on the final grit with which the wood was sanded. For instance, the large valleys left by 80 grit sandpaper will absorb much more pigment than will the fine tracks left by 150 grit sandpaper. For this reason it is important to prepare samples with the actual grits and the actual stains and finishes.
Contain dust
|
Vacuum
|
Sanding
|
Polishing
|
13 • SITE SANDING / REFINISHING OF EXISTING HARDWOOD FLOORING
.01 Immediately before sanding all floor surfaces must be swept clean or vacuumed and inspected for any protruding nail heads and loose boards and any damaged or defective boards replaced and all defects remedied.
.02 Most strip / plank solid hardwood flooring is 19 mm (3/4") thick and can be sanded and refinished a number of times. Thinner floors however, such as 13 mm (1/2") or 10 mm (3/8") thick material, should be refinished with caution as repeated sanding could wear through to reveal fastenings. To determine an existing hardwood floor thickness, remove a floor heating register or shoe mold and baseboard so that an edge of the flooring can be observed and measured.
.03 When refinishing thinner floors, as little of the surface as is absolutely necessary should be removed, except for 8 mm (5/16") face-nailed square edge or 8 mm (5/16") square edge installed in mastic. On square edge strip flooring that is face nailed, the nails should be driven slightly below the surface of the wood to permit sanding the floor.
.04 "Open face" paper should be used to remove the existing finish. The heat and abrasion of sanding operations make the old finish gummy and will quickly clog normal sanding paper. When new wood is reached, regular paper can be used for the final finishing cuts. If the old floor has been painted several times, paint remover should be used to uncover the wood surface. Old paint requires far too much sanding to make this a practical means of removal.
.05 The number of cuts required during refinishing operations will be largely determined by the condition of the old floor and the thickness of the finish being removed. If the surface is in good shape and has no build-up of old finish and wax, one pass with the disc sander and extra-fine paper may be sufficient. All the old finish must be removed.
.06 If the floor is badly scarred or dished, as many cuts as are necessary should be made to get a smooth, unblemished surface.
.01 Immediately before sanding all floor surfaces must be swept clean or vacuumed and inspected for any protruding nail heads and loose boards and any damaged or defective boards replaced and all defects remedied.
.02 Most strip / plank solid hardwood flooring is 19 mm (3/4") thick and can be sanded and refinished a number of times. Thinner floors however, such as 13 mm (1/2") or 10 mm (3/8") thick material, should be refinished with caution as repeated sanding could wear through to reveal fastenings. To determine an existing hardwood floor thickness, remove a floor heating register or shoe mold and baseboard so that an edge of the flooring can be observed and measured.
.03 When refinishing thinner floors, as little of the surface as is absolutely necessary should be removed, except for 8 mm (5/16") face-nailed square edge or 8 mm (5/16") square edge installed in mastic. On square edge strip flooring that is face nailed, the nails should be driven slightly below the surface of the wood to permit sanding the floor.
.04 "Open face" paper should be used to remove the existing finish. The heat and abrasion of sanding operations make the old finish gummy and will quickly clog normal sanding paper. When new wood is reached, regular paper can be used for the final finishing cuts. If the old floor has been painted several times, paint remover should be used to uncover the wood surface. Old paint requires far too much sanding to make this a practical means of removal.
.05 The number of cuts required during refinishing operations will be largely determined by the condition of the old floor and the thickness of the finish being removed. If the surface is in good shape and has no build-up of old finish and wax, one pass with the disc sander and extra-fine paper may be sufficient. All the old finish must be removed.
.06 If the floor is badly scarred or dished, as many cuts as are necessary should be made to get a smooth, unblemished surface.
14 • FINAL PREPARATION FOR SITE FINISHING
.01 When machine and hand sanding is completed the floor should be vacuumed clean using a heavy-duty commercial type vacuum and all dust wiped from windows, sills, doors, door frames, baseboards and the floor, using a painter's tack rag.
.02 To ensure that surfaces are completely sanded flooring surfaces may be sponged or wiped with water, alcohol, or solvents to show any uneven sanding or marks, or in the case of existing flooring, to show areas that may contain residual finish, oil, or glue.
.03 After the above noted sanding and cleaning, floor surfaces should be ready for the application of dyes, stains, or fillers.
.04 All cracks and nail holes in flooring should be filled using a commercial putty of a matching colour, which is compatible with stain and / or finish. Filler should be applied with a putty knife. When dry, surfaces should be hand sanded with fine sand paper.
.05 The first coat of stain or other finish should be applied the same day that sanding is completed. This prevents a raised grain condition, which creates a rough surface.
.06 Where open grain wood will be difficult to stain, water or grain popping may be used to open up the grain to allow a stain to absorb or penetrate more evenly. This must be done by a competent trades person skilled in the use of this technique.
.01 When machine and hand sanding is completed the floor should be vacuumed clean using a heavy-duty commercial type vacuum and all dust wiped from windows, sills, doors, door frames, baseboards and the floor, using a painter's tack rag.
.02 To ensure that surfaces are completely sanded flooring surfaces may be sponged or wiped with water, alcohol, or solvents to show any uneven sanding or marks, or in the case of existing flooring, to show areas that may contain residual finish, oil, or glue.
.03 After the above noted sanding and cleaning, floor surfaces should be ready for the application of dyes, stains, or fillers.
.04 All cracks and nail holes in flooring should be filled using a commercial putty of a matching colour, which is compatible with stain and / or finish. Filler should be applied with a putty knife. When dry, surfaces should be hand sanded with fine sand paper.
.05 The first coat of stain or other finish should be applied the same day that sanding is completed. This prevents a raised grain condition, which creates a rough surface.
.06 Where open grain wood will be difficult to stain, water or grain popping may be used to open up the grain to allow a stain to absorb or penetrate more evenly. This must be done by a competent trades person skilled in the use of this technique.
15 • APPLICATION OF SEALERS
.01 A penetrating sealer is recommended for most flooring. The sealer soaks into the wood pores and hardens to seal the floor against dirt and most stains. It wears only as the wood wears and will not chip or scratch. After years of wear the floor can usually be refinished without sanding, by cleaning and applying another coat of sealer or special reconditioning product. Worn areas can be refinished without showing lap marks where the new finish is applied over the old.
.02 There are two basic types of sealers, distinguished by drying time required.
.03 Some sealers produce satisfactory results with one coat but most manufacturers recommend two coats or one coat plus a special top dressing.
.04 Sealers shall be allowed to dry, and then should be buffed using an electric polisher equipped with a No.2 steel wool pad or hand buffed using the same steel wool material.
Note: Some manufacturer's directions call for rubbing the sealer into the wood with steel wool pads on an electric buffer while the sealer is still wet.
.05 For a satin finish, steel wool is used on each coat and wax applied to protect and add more luster to the finish. For an even greater gloss and maximum protection from spills and surface moisture, a single application of penetrating sealer should be used (buffed with steel wool) followed by two coats of polyurethane.
.06 Most manufacturers of penetrating sealer finishes also make a reconditioning product for use when traffic or other conditions cause discoloration or wear of the finish. These products restore the floor to its original appearance without the need for sanding. They may also be used on most pre-finished flooring (finished at the factory) subject to verification by the flooring manufacturer.
.07 To determine if an existing or pre-finished floor was originally finished with a penetrating sealer, the surface (in a corner or some other inconspicuous space) should be scratched with a coin or other sharp-edge object. If the finish does not flake off, a penetrating seal was probably used and a reconditioning product can be applied. If the condition of the flooring is very bad, sanding and the application of a complete new finish may be required.
.01 A penetrating sealer is recommended for most flooring. The sealer soaks into the wood pores and hardens to seal the floor against dirt and most stains. It wears only as the wood wears and will not chip or scratch. After years of wear the floor can usually be refinished without sanding, by cleaning and applying another coat of sealer or special reconditioning product. Worn areas can be refinished without showing lap marks where the new finish is applied over the old.
.02 There are two basic types of sealers, distinguished by drying time required.
- Normal (or slow drying) sealers can be used safely by anyone.
- Fast-drying sealers should be used only by a professional who is accustomed to handling and applying them and can complete the job within the allotted drying time and to avoid lap marks or a splotchy appearance.
.03 Some sealers produce satisfactory results with one coat but most manufacturers recommend two coats or one coat plus a special top dressing.
.04 Sealers shall be allowed to dry, and then should be buffed using an electric polisher equipped with a No.2 steel wool pad or hand buffed using the same steel wool material.
Note: Some manufacturer's directions call for rubbing the sealer into the wood with steel wool pads on an electric buffer while the sealer is still wet.
.05 For a satin finish, steel wool is used on each coat and wax applied to protect and add more luster to the finish. For an even greater gloss and maximum protection from spills and surface moisture, a single application of penetrating sealer should be used (buffed with steel wool) followed by two coats of polyurethane.
.06 Most manufacturers of penetrating sealer finishes also make a reconditioning product for use when traffic or other conditions cause discoloration or wear of the finish. These products restore the floor to its original appearance without the need for sanding. They may also be used on most pre-finished flooring (finished at the factory) subject to verification by the flooring manufacturer.
.07 To determine if an existing or pre-finished floor was originally finished with a penetrating sealer, the surface (in a corner or some other inconspicuous space) should be scratched with a coin or other sharp-edge object. If the finish does not flake off, a penetrating seal was probably used and a reconditioning product can be applied. If the condition of the flooring is very bad, sanding and the application of a complete new finish may be required.
16 • APPLICATION OF PENETRATING SEALERS WITH STAIN
.01 If other than a natural finish is desired, staining must be the first step in the finishing process. These materials are available in a number of wood tones and several colours, with the application to be in strict accordance with the manufacturer's directions.
.01 If other than a natural finish is desired, staining must be the first step in the finishing process. These materials are available in a number of wood tones and several colours, with the application to be in strict accordance with the manufacturer's directions.
17 • APPLICATION OF PIGMENTED WIPING STAINS
.01 When machine and hand sanding is completed the floor should be vacuumed clean and all dust wiped from windows, sills, doors, door frames, baseboards and the floor, using a painter's tack rag.
.02 Wiping stains are a penetrating oil-resin vehicle to which pigments have been added. The pigments are not in solution, but in suspension, so the material must be stirred regularly during use to maintain a uniform colour. The pigment collects in the open pores of the wood and this accentuates the grain pattern. The application of wiping stains shall be in strict accordance with the manufacturer's directions.
.01 When machine and hand sanding is completed the floor should be vacuumed clean and all dust wiped from windows, sills, doors, door frames, baseboards and the floor, using a painter's tack rag.
.02 Wiping stains are a penetrating oil-resin vehicle to which pigments have been added. The pigments are not in solution, but in suspension, so the material must be stirred regularly during use to maintain a uniform colour. The pigment collects in the open pores of the wood and this accentuates the grain pattern. The application of wiping stains shall be in strict accordance with the manufacturer's directions.
Staining
18 • APPLICATION OF OTHER STAINS
.01 When machine and hand sanding is completed, the floor should be vacuumed clean and all dust wiped from windows, sills, doors, door frames, baseboards and the floor, using a painter's tack rag.
.02 Water based hardwood floor stains are also available. The design authority should consult with local hardwood flooring suppliers for types available.
.01 When machine and hand sanding is completed, the floor should be vacuumed clean and all dust wiped from windows, sills, doors, door frames, baseboards and the floor, using a painter's tack rag.
.02 Water based hardwood floor stains are also available. The design authority should consult with local hardwood flooring suppliers for types available.
19 • APPLICATION OF SURFACE FINISHES
.01 These finishes, including polyurethane, water base urethane, oil modified urethane, moisture cured urethane and urea-formaldehyde, remain on the surface of the floor and form a protective coating. They are generally applied over a properly sanded and sealed floor. They are the best choice for areas wherever there is exposure to water splashing and spills.
.02 The application of surface finishes must be in strict accordance with the material manufacturer's instructions for the type of wood material.
.03 Note that the adhesion of surface finishes is affected by wax and grease as well as some types of stains, bleaches or sealers. One brand or type of finish may not be compatible with another. To determine if a surface finish will be compatible, conduct a test to ensure that the finish will adhere and dry properly. This is particularly important when refinishing an old floor, since some of the old finish may have penetrated the wood below the level to which it is sanded.
.04 Bleaching wood flooring retains the general tone and reduces variations in colour without obscuring the grain pattern. Before using a bleach, the flooring must be clean and free from oils, grease, and old finish that might repel the bleach and give an uneven effect. Since bleaches have a water base, their use will cause the grain of the flooring to raise. Sanding with fine paper after use will be necessary to restore the floor to the smooth surface required. Bleaches that have been specially formulated for wood flooring should only be used.
.05 Manufacturer's instructions for application of bleach must be complied with. A test area should be made in an inconspicuous place, since the length of time the bleach remains on the floor will affect the degree of colour removal. Multiple applications should be avoided, since subsequent applications soften the wood, make wood fiber brittle and prone to dent, and affect finish adherence. A white stain may be applied before the surface finish. All products must be non-ambering and should be compatible with the stain and / or sealer used.
.06 Sheen levels: The level of sheen is derived by the amount of light reflection created by the finish. Each finish manufacturer can use different application procedures that can affect sheen levels. There are different sheen level options (listed below). Products supplied with lower sheen levels such as Satin or Matte, can help disguise normal wear and tear and acceptable imperfections in the sanding and finishing process. The glossier (shinier) the finish, the more critical light will highlight issues.
.01 These finishes, including polyurethane, water base urethane, oil modified urethane, moisture cured urethane and urea-formaldehyde, remain on the surface of the floor and form a protective coating. They are generally applied over a properly sanded and sealed floor. They are the best choice for areas wherever there is exposure to water splashing and spills.
.02 The application of surface finishes must be in strict accordance with the material manufacturer's instructions for the type of wood material.
.03 Note that the adhesion of surface finishes is affected by wax and grease as well as some types of stains, bleaches or sealers. One brand or type of finish may not be compatible with another. To determine if a surface finish will be compatible, conduct a test to ensure that the finish will adhere and dry properly. This is particularly important when refinishing an old floor, since some of the old finish may have penetrated the wood below the level to which it is sanded.
.04 Bleaching wood flooring retains the general tone and reduces variations in colour without obscuring the grain pattern. Before using a bleach, the flooring must be clean and free from oils, grease, and old finish that might repel the bleach and give an uneven effect. Since bleaches have a water base, their use will cause the grain of the flooring to raise. Sanding with fine paper after use will be necessary to restore the floor to the smooth surface required. Bleaches that have been specially formulated for wood flooring should only be used.
.05 Manufacturer's instructions for application of bleach must be complied with. A test area should be made in an inconspicuous place, since the length of time the bleach remains on the floor will affect the degree of colour removal. Multiple applications should be avoided, since subsequent applications soften the wood, make wood fiber brittle and prone to dent, and affect finish adherence. A white stain may be applied before the surface finish. All products must be non-ambering and should be compatible with the stain and / or sealer used.
.06 Sheen levels: The level of sheen is derived by the amount of light reflection created by the finish. Each finish manufacturer can use different application procedures that can affect sheen levels. There are different sheen level options (listed below). Products supplied with lower sheen levels such as Satin or Matte, can help disguise normal wear and tear and acceptable imperfections in the sanding and finishing process. The glossier (shinier) the finish, the more critical light will highlight issues.
- Gloss - Highly reflective (site applied). Likely to show wear and tear sooner than a finish sheen that reflects light less such as Satin or Matte.
- Semi-Gloss
- Satin
- Matte - Lower light reflection
20 • APPLICATION OF DECORATIVE BORDERS AND PATTERNS
.01 Decorative borders or overall floor patterns can be applied to hardwood floors with the use of stencils. This work should be done by a professional finisher familiar with these procedures.
.01 Decorative borders or overall floor patterns can be applied to hardwood floors with the use of stencils. This work should be done by a professional finisher familiar with these procedures.
21 • FINISHING HARDWOOD SPORTS FLOORING
.01 Sanding and finishing hardwood sports flooring for gymnasiums, handball, squash, or racquet ball courts, or other specialty sports areas is similar to the procedures described for other wood flooring installations, except as follows.
.02 Special finishing products are manufactured to provide the gloss, slip resistance, and abrasion resistance required, as well as to permit painting of game lines. Only products specifically manufactured for such applications should be used. The specific finishing instructions provided with each product must be followed. Deviations from the recommended procedure may affect quality and performance of the finish.
Note: The following are MFMA recommended procedures for sealing, sanding, court lining and finishing of hardwood sports flooring.
.03 Hardwood sports flooring must be sanded after all other trades are finished and all equipment removed from the area (except bleachers if resting on gym floors – although it is best if they are installed after the flooring has been finished). Sanding is done with a minimum of three cuts using coarse, medium, and fine sand papers. Final sanding of pattern floors should be performed with a screen and disc sander. This final sanding should provide a smooth and even surface, free from scratches. After sanding, all surfaces including bases must be vacuumed to remove all grit and dust from the area.
.04 There are two basic methods for the application of sealers and finishes for gymnasium and handball court-use. These are.
Another recommended method is a three-coat application of moisture-cured urethane.
Note: In all cases the floor should be thoroughly cleaned prior to the first coat of floor sealer.
.05 After sanding and cleaning, liberal and uniform coats of penetrating sealer are applied at coverage rates as recommended by the manufacturer using an appropriate applicator (e.g. clean lambs wool), allowed to dry, buffed, and then cleaned thoroughly. If a four coat method is being used a second coat of penetrating sealer should be applied in the same manner as first.
.06 After sealing the flooring surface is allowed to dry and then is lightly sanded or disced using a 150 grit paper or #2 steel wool (except as noted). The floor is then vacuumed and double tack ragged in preparation for court layout and painting.
Caution: Where water-borne finishes are used steel wool must not be used.
Note: Adequate filtered ventilation must be provided during the entire sealing, finishing, and curing processes.
.07 Game / Court Lines: The Design Authority is responsible for furnishing game line drawings with colour selections prior to sanding and finishing. Game markings are applied in accordance with pre-approved game line drawings using a paint that is compatible with the floor sealer and finish, and with the aid of a precision taping machine or striping tool. When using masking tape, the tape should be pulled / removed as soon as the paint starts to dry or set. After game markings have dried thoroughly they should be lightly buffed with steel wool and the floor surface cleaned.
Note: Durable alkyd enamels specially formulated for such lines and other markings are available. Two component epoxy enamels must be used under moisture cured urethanes finishes.
.08 Even coats of finish at rates recommended by the manufacturer shall be applied with the grain, using an appropriate applicator or other method pre-approved by the manufacturer. The first coat of finish shall be allowed to dry thoroughly and then be burnished with #2 steel wool (except as noted) or screened to break surface tension for bonding of the final coat. This surface should then be vacuumed double tack ragged and final coat of finish applied at a rate recommended by the manufacturer. After the final coat is applied, the floor surface shall not be used for a minimum of 72 hours and heavy traffic shall not be allowed on floor for at least a week.
Note: During finishing and drying time, the area must be free of dust and dirt, and air currents that carry dust and dirt must be avoided. Temperatures of rooms and materials should be approximately 18°C, or above during treatment. And after finishing is completed, temperature and humidity should be maintained at or near occupancy levels.
.09 Protection:
Note: Some manufacturers of surface finishes do not recommend waxing. The design authority should check manufacturer's recommendations. Waxing a commercial installation creates a slip hazard. Gymnasium or other sports floors should never be waxed. Such floors require special maintenance procedures and products.
.01 Sanding and finishing hardwood sports flooring for gymnasiums, handball, squash, or racquet ball courts, or other specialty sports areas is similar to the procedures described for other wood flooring installations, except as follows.
.02 Special finishing products are manufactured to provide the gloss, slip resistance, and abrasion resistance required, as well as to permit painting of game lines. Only products specifically manufactured for such applications should be used. The specific finishing instructions provided with each product must be followed. Deviations from the recommended procedure may affect quality and performance of the finish.
Note: The following are MFMA recommended procedures for sealing, sanding, court lining and finishing of hardwood sports flooring.
.03 Hardwood sports flooring must be sanded after all other trades are finished and all equipment removed from the area (except bleachers if resting on gym floors – although it is best if they are installed after the flooring has been finished). Sanding is done with a minimum of three cuts using coarse, medium, and fine sand papers. Final sanding of pattern floors should be performed with a screen and disc sander. This final sanding should provide a smooth and even surface, free from scratches. After sanding, all surfaces including bases must be vacuumed to remove all grit and dust from the area.
.04 There are two basic methods for the application of sealers and finishes for gymnasium and handball court-use. These are.
- Four-Coat Specification: Two coats of sealer and two coats of finish.
- Three-Coat Specification: One coat sealer and two coats of finish.
Another recommended method is a three-coat application of moisture-cured urethane.
Note: In all cases the floor should be thoroughly cleaned prior to the first coat of floor sealer.
.05 After sanding and cleaning, liberal and uniform coats of penetrating sealer are applied at coverage rates as recommended by the manufacturer using an appropriate applicator (e.g. clean lambs wool), allowed to dry, buffed, and then cleaned thoroughly. If a four coat method is being used a second coat of penetrating sealer should be applied in the same manner as first.
.06 After sealing the flooring surface is allowed to dry and then is lightly sanded or disced using a 150 grit paper or #2 steel wool (except as noted). The floor is then vacuumed and double tack ragged in preparation for court layout and painting.
Caution: Where water-borne finishes are used steel wool must not be used.
Note: Adequate filtered ventilation must be provided during the entire sealing, finishing, and curing processes.
.07 Game / Court Lines: The Design Authority is responsible for furnishing game line drawings with colour selections prior to sanding and finishing. Game markings are applied in accordance with pre-approved game line drawings using a paint that is compatible with the floor sealer and finish, and with the aid of a precision taping machine or striping tool. When using masking tape, the tape should be pulled / removed as soon as the paint starts to dry or set. After game markings have dried thoroughly they should be lightly buffed with steel wool and the floor surface cleaned.
Note: Durable alkyd enamels specially formulated for such lines and other markings are available. Two component epoxy enamels must be used under moisture cured urethanes finishes.
.08 Even coats of finish at rates recommended by the manufacturer shall be applied with the grain, using an appropriate applicator or other method pre-approved by the manufacturer. The first coat of finish shall be allowed to dry thoroughly and then be burnished with #2 steel wool (except as noted) or screened to break surface tension for bonding of the final coat. This surface should then be vacuumed double tack ragged and final coat of finish applied at a rate recommended by the manufacturer. After the final coat is applied, the floor surface shall not be used for a minimum of 72 hours and heavy traffic shall not be allowed on floor for at least a week.
Note: During finishing and drying time, the area must be free of dust and dirt, and air currents that carry dust and dirt must be avoided. Temperatures of rooms and materials should be approximately 18°C, or above during treatment. And after finishing is completed, temperature and humidity should be maintained at or near occupancy levels.
.09 Protection:
- To protect a penetrating sealer type finish, either a coat of liquid buffing wax / cleaner or floor paste wax should be applied. Only brands that are designated for hardwood floors should be used and if a liquid type, only a solvent-based type is suitable. After the finish seal coat is thoroughly dry, wax could be applied and polished with a machine buffer.
- Floor wax will give a lustrous sheen to the floor and will form a protective film that helps prevent scratches and dirt from penetrating the finish.
Note: Some manufacturers of surface finishes do not recommend waxing. The design authority should check manufacturer's recommendations. Waxing a commercial installation creates a slip hazard. Gymnasium or other sports floors should never be waxed. Such floors require special maintenance procedures and products.
22 • REFINISHING
.01 Solid hardwood strip, plank, and parquet flooring can be refinished and/or recoated. Engineered / laminate flooring may be refinished depending on the thickness of the top layer or veneer subject to specific recommendations of the material manufacturer and may be recoated depending on the type of factory finish and the material manufacturer recommendations.
.02 As a general rule, surface finishes should never be site applied to factory finished hardwood flooring without first contacting the flooring manufacturer.
.03 The type of refinishing depends on the amount of wear and the material to be refinished and may take one of two forms:
.04 The screen (light sanding) and coat procedure "refreshes" an existing finish that is dull and/or has minor wear by preparing it and applying another application of finish (usually one coat). Frequent screen and coat applications can eliminate the need for complete refinishing at a later date. Without the screening process, any new finish is very likely to peel off. Minor surface scratches can be removed but ones that are deep into the finish or the material itself cannot and require other measures.
If this procedure is considered the following must be ascertained:
.01 Solid hardwood strip, plank, and parquet flooring can be refinished and/or recoated. Engineered / laminate flooring may be refinished depending on the thickness of the top layer or veneer subject to specific recommendations of the material manufacturer and may be recoated depending on the type of factory finish and the material manufacturer recommendations.
.02 As a general rule, surface finishes should never be site applied to factory finished hardwood flooring without first contacting the flooring manufacturer.
.03 The type of refinishing depends on the amount of wear and the material to be refinished and may take one of two forms:
- Screening and coating the existing finish (also known as buff and topcoat or top coating), or
- Sanding and refinishing (removal of existing finish down to bare wood).
.04 The screen (light sanding) and coat procedure "refreshes" an existing finish that is dull and/or has minor wear by preparing it and applying another application of finish (usually one coat). Frequent screen and coat applications can eliminate the need for complete refinishing at a later date. Without the screening process, any new finish is very likely to peel off. Minor surface scratches can be removed but ones that are deep into the finish or the material itself cannot and require other measures.
If this procedure is considered the following must be ascertained:
- Type of cleaners that have been used as they may affect any new application.
- Type of finish on flooring:
a. Wax Finish: Waxed floors cannot be screened and coated unless the wax is completely removed. To verify this, use an area not visible (e.g. in a closet) and test by applying a few drops of water on top of the finish and allow it to sit for 15 minutes. If white spots appear then it is a waxed finish.
b. Shellac and Varnish Finishes: These were a common finish on hardwood floors dating before the mid-sixties and must be completely removed for new urethane finishes.
c. Aluminum Oxide Finish: Refinishing / recoating this relatively new finish will be dependent on what stage the aluminum oxide was added (i.e., between the first few coats or in final ones). This must be ascertained from the flooring manufacturer prior to any recoating application.
b. Shellac and Varnish Finishes: These were a common finish on hardwood floors dating before the mid-sixties and must be completely removed for new urethane finishes.
c. Aluminum Oxide Finish: Refinishing / recoating this relatively new finish will be dependent on what stage the aluminum oxide was added (i.e., between the first few coats or in final ones). This must be ascertained from the flooring manufacturer prior to any recoating application.
.05 Complete refinishing depends on the amount of wear and the material to be refinished. Removal of finishes with aluminum oxide will be more labour intensive and costlier due to the difficulty in removing the finish.
.06 Preparation Requirements: The following must be considered:
- Removal of all furniture, floor coverings, and draperies in area to be finished.
- Protecting / sealing other areas and furniture from sanding dust by use of plastic sheeting, drop cloths, etc.
- Sealing of heating system grilles and ducting to inhibit dust spread and to prevent dust from spreading over finish.
- Regulating the heating and/or air-conditioning system to maintain proper temperature for application and curing of materials.
- Repair or replacement of damaged, warped, and loose flooring.
- Repair of dents and filling of scratches and cracks.
- Resetting or removal of loose fasteners.
- Depending on the finish used, furniture should not be placed back into areas until it is safe to do so.
- Traffic must be kept away from newly refinished areas until the finish has had a chance to cure.
- During cleanup and reinstallation of furniture, chair protectors should be used and/or leg bottoms should be cleaned to eliminate any trapped grit that will cause harm to the finish.
.07 Do-it-Yourself or Professional Refinishing
- Due to the complexity of refinishing (selection and proper application of finishes) as well as the care and procedures required in the use of specialized equipment, NFCA recommends that any refinishing be done by thoroughly trained professionals.