D03C - MATERIAL GUIDES - HARDWOOD FLOORING

D03C-1 Hardwood 
D03C-2 Solid hardwood flooring
D03C-3 Engineered hardwood flooring
D03C-4 Laminate flooring
D03C-5 Hardwood sports flooring
D03C-6 Specialty hardwood flooring
D03C-7 Hardwood flooring edges
D03C-8 Hardwood flooring textures and patterns
D03C-9 Hardwood flooring molding, trims, and accessories
D03C-10 Hardwood stairs
D03C-11 Hardwood flooring underlayments
D03C-12 Hardwood flooring adhesives
D03C-13 Hardwood flooring fastenings
D03C-14 Special installation systems
D03C-15 Special installation requirements
D03C-16 Hardwood finishing
Preface:
This study guide covers solid strip, plank, and parquet hardwood and engineered (or laminated) flooring and related materials. The information given is a guide only and cannot fully cover all aspects of such flooring and its installation. Specifiers and/or persons selecting such products should verify all facts relative to the particular project requirements.

This study guide does not cover laminate wood flooring which is included under Part E03C - Material Guide (Laminate Flooring).

To fully understand how to choose hardwood flooring for a residential, commercial, or an institutional installation, a thorough knowledge of hardwood species, grades, finishes, and related materials as well as types of installation systems and methods is essential. The following information is offered as a guide only and will hopefully assist all those who have to deal with this type of flooring (designers, suppliers, installers, Owners, etc.) in becoming more aware of the issues concerned in choosing an appropriate hardwood type, finish, and installation method required to suit a project's requirements.
1 • HARDWOOD
.01 What is Hardwood:
  1. Hardwood is a description applied to woods from deciduous broad-leafed trees (Angiosperms) that produce a fruit or nut and generally go dormant in the winter in contrast to that from evergreen or conifer (cone bearing) trees or softwoods.
  2. The term "hardwood" has no reference to the actual hardness of the wood or hardwood flooring as both open-grain and close-grain hardwoods and some softwoods are used in hardwood flooring. There are also both hardwoods and softwoods that aren't recommended for "hardwood" flooring because they are not hard enough to withstand heavy wear and tear.
  3. Hardwoods suitable for use in flooring include such domestic (North American) species as Oak, Ash, Cherry, Maple, and Poplar as well as such imported (tropical) species as Mahogany, Rosewood, Teak, and Wenge.
  4. Heading the list of the most suitable and widely used hard, open-grain wood is Oak. Northern Walnut, Pecan, Ash, Elm, and Chestnut are also open-grain hardwoods. Among close-grain hardwoods are Maple, Birch, and Beech. 
.02 Hardwood Species
  1. More than 50 species of wood are used for hardwood flooring. These come from both domestic (North American) sources and from many foreign sources (Central and South America, Europe, Africa, Asia, Australia, and the Far East) and span the spectrum of colour options, hardness, and price ranges.
  2. For an explanation of species refer to Part D03D - Material Guide - Species . 
.03 Hardwood Grading:
  1. Material for hardwood flooring is manufactured from hardwood or softwood lumber that has been kiln-dried to a specific moisture content level, air-cooled, cut into appropriate sizes, and then accurately milled into strip or plank form with required profiles (e.g. tongue and groove edges, and square, eased, or bevelled top faces).
  2. Once such milling is complete the material is carefully graded based on a number of parameters or grading rules that have been established by various industry associations that were established by hardwood manufacturers. Some of these associations are:
    1. Canadian Lumber Association (CLA)
    2. Maple Flooring Manufacturers Association (MFMA).
    3. National Wood Flooring Association (NWFA). (National Oak Flooring Manufacturers Association NOFMA)
    4. Quebec Wood Export Bureau (QWEB).
    5. Southern Pine Inspection Bureau (SPIB).
  3. These associations have established minimum standards or rules in regard to the surface characteristics, required lengths, milling tolerances, and moisture content of milled wood within a species and also groups the material having similar qualities into like groups or grades. In addition to creating grades, the associations also provide an impartial service to settle grading disputes and perform grading inspections. This brings a degree of consistency in products from different manufacturers who choose to adhere to these established grading rules.
  4. Manufacturers who do not belong to these associations or adhere to the association grading rules may develop classifications and "proprietary" grades for their own flooring materials.
  5. For specific species grading requirements, refer to D03E - Material Guide - Grades.
  6. Most manufacturers of engineered and pre-finished flooring follow their own grading rules. At present, no association standards exist for engineered wood floors.
2 • SOLID HARDWOOD FLOORING
.01 Solid hardwood flooring is milled from hardwood or softwood into strip or plank form, or cut into fillet strips and assembled into tile form (parquet).

Solid hardwood strip and plank flooring is produced in various thicknesses and widths in random lengths from 300 mm (12") to 2135 mm (84") although longer lengths may be available in some species and grades. Solid parquet fillets are cut to appropriate sizes to suit tile requirements. This type of solid flooring material can be site or pre-finished and because of its thickness can be refinished or recoated several times during its lifetime.

Note in regard to Availability: In all cases the thicknesses, widths, lengths, edge and top face details for both solid and engineered strip, plank, and parquet flooring as noted herein must be verified with the applicable grading association for the species and grade selected.

Note in regard to Installation: "Solid" hardwood flooring is sensitive to moisture and the installation of it is not recommended on concrete substrate surfaces on or below grade levels.

.02 Solid Strip Flooring: These are solid hardwood strips (material less than 75 mm (3") in nominal width) that are designed to be installed in parallel rows. Typically they are all of the same width but may also be combined with planks.
  1. Thicknesses: Varies with species and edge profile - 8 mm (5/16"), 9 mm (11/32"), 10 mm (3/8"), 13 mm (1/2"), 19 mm (3/4"), 20 mm (25/32"), and 26 mm (33/32").
  2. Widths: Varies with species and thickness - 38 mm (1-1/2"), 50 mm (2"), 57 mm (2-1/4"), and 83 mm (3 1/4").
  3. Lengths: Random (Refer to grading rules).
  4. Side Edges: Tongue and groove and square.
  5. Top Face Edges: Square, eased, and bevelled (verify with manufacturer).
  6. Species: Available in Oak (Red and White) Beech, Birch, Hard Maple, and Pecan.
  7. Grading: In accordance with CLA, NOFMA, MFMA, SPIB, or other official rules.
  8. Finish: Factory pre-finished or unfinished for sanding and finishing on site.
  9. Installation: May be mechanically fastened (concealed / side nailed in tongue or face nailed) or glued down (but either method not directly to concrete) over an acceptable substrate in accordance with manufacturer's recommendations and applicable grading association and NFCA requirements.
  10. Availability: Refer to specific manufacturer / supplier.
.03 Solid Plank Flooring: These are solid hardwood planks in nominal widths from 75 mm (3") to 200 mm (8") that are designed to be installed in parallel rows. Plank flooring can be combined with strip flooring and/or in alternate widths and/or random lengths.
  1. Thicknesses: Varies with species - 19mm (3/4") with 22 mm (7/8") also available from some manufactures.
  2. Widths: Varies with species - 75 mm (3") to 200 mm (8"), although wider widths may be available in some species and grades.
  3. Lengths: Random (refer to grading rules / verify with manufacturer).
  4. Side Edges: Typically tongue and groove.
  5. Top Face: Edges may be square, eased, or bevelled (verify with manufacturer).
  6. Species: Available in Red or White Oak, Beech, Birch, Hard Maple, and Pecan.
  7. Grading: In accordance with CLA, NOFMA, MFMA, SPIB, or other official rules.
  8. Finish: Factory pre-finished or unfinished for sanding and finishing on site.
  9. Installation: Typically mechanically fastened (concealed / side nailed in tongue or face nailed) or may also be glued down (but either method not directly to concrete) over an acceptable substrate in accordance with manufacturer's recommendations and applicable grading association and NFCA requirements.
  10. Availability: Refer to specific manufacturer / supplier.
.04 Solid Parquet Flooring: This type of flooring consists of small wood slats or fillets of solid hardwood assembled in units or "tiles" that may consist of individual squares, or units with slats arranged in various patterns, or with slats of same or contrasting species.
  1. Thicknesses: 8 mm (5/16") and 19 mm (3/4").
  2. Slat Sizes: Varies depending on pattern selected.
  3. Unit or Tile Sizes: varies from 100 mm (4") up to 300 mm (12") square but may vary depending on pattern selected. Multiple tiles (usually four depending on size) with a common paper or mesh backing may also be available. Verify with manufacturer.
  4. Side Edges: Usually square although tongue and groove may be available for some large tiles (verify with manufacturer).
  5. Top Face Edges: Usually square although other edge types (eased or bevelled) may be available (verify with manufacturer).
  6. Species: Available in Oak (Red and White) Maple, Black Walnut, Cherry, Cedar, and Ash. Note - Not all patterns are available in the species listed.
  7. Grading: In accordance with CLA, NOFMA, MFMA, or other official grading rules.
  8. Patterns: Typically square tiles, but also available in other patterns (verify with manufacturer for variety available).
  9. Finish: Factory pre-finished or unfinished for sanding and finishing on site.
  10. Installation: Typically glued down but may also be mechanically fastened (but either method not directly to solid board subfloors) over an acceptable substrate in accordance with manufacturer's recommendations and applicable grading association and NFCA requirements.
  11. Availability: Refer to specific manufacturer / supplier.
.05 Self-Adhesive Solid Parquet Flooring: This type of flooring consists of parquet flooring panels as noted above complete with a self-adhesive (peel and stick) backing. The design authority must verify all requirements (e.g., species, patterns, etc.) and availability of this type of parquet flooring with suppliers before use.
3 • ENGINEERED HARDWOOD FLOORING
.01 Engineered flooring (also referred to as laminated not laminate flooring) consists of a décor or pattern layer of either sawn solid hardwood or a rotary peeled or flat cut slice of hardwood veneer bonded to a plywood core with plies at right angles to the grain of the top and bottom layer, a core layer of either plywood (with plies at right angles to grain of top and bottom layer), medium density fibreboard (MDF), or high density fibreboard (HDF), and a bottom balancing layer. This minimum three-layer assembly is adhesive bonded together in accordance with manufacturer's requirements using heat and pressure as applicable.

.02 Engineered wood flooring is manufactured in single strips or planks, multiple strip and/or plank panels, and in parquet form using a wide variety of domestic and exotic hardwood species. This type of flooring is either pre-finished (sawn or veneer slice décor layer types) or unfinished (sawn décor layer only) and may be installed as a floating assembly with friction fit ("locked" or "clicked") joints, or may be mechanically fastened (i.e., stapled or nailed), or glued to an approved substrate as recommended by the manufacturer.

.03 The types of engineered wood flooring having a thin veneer layer can be screened (lightly sanded) and re-coated but usually cannot be sanded and refinished again once they become worn. Engineered wood flooring having a thicker layer of hardwood can be screened and recoated or re-sanded and refinished a number of times depending on the thickness of the top layer. In either case, screening and recoating or sanding and refinishing engineered flooring must be verified with the manufacturer before attempted.

​.04 Standards: Engineered flooring is manufactured in both North American and Europe and its fabrication is therefore governed by a variety of standards, including the following:
  1. ANSI/HPVA EF 2012, Standard for Engineered Wood Flooring. This is a joint American National Standards Institute (ANSI) / Hardwood Plywood Manufacturers Association (HPMA) standard. (a North American standard)
  2. EN 13629, Wood flooring - Solid pre-assembled hardwood boards. This is a European Norm standard.
  3.  Note: The design authority must determine what requirements and standards are appropriate when comparing engineered flooring from these two sources. If both North American and European engineered flooring is used then the minimum requirements of the one should govern both as long as the requirements are carefully evaluated.
.05 Availability: In all cases, thickness, widths, lengths, edge and top face details for engineered strips, planks, panels, and parquet flooring as noted herein must be verified with the applicable manufacturer / supplier for the species and grade selected.

.06 Installation: Engineered hardwood flooring may be installed above, on, or below grade BUT verify with specific product manufacturer for installation requirements where moisture may be a problem (i.e. on concrete substrate surfaces on or below grade levels).

.07 Engineered Strip and Plank Flooring: These are single or multiple strips or planks assembled in accordance with requirements noted above that are designed to be installed in parallel rows.
  1. Thicknesses: 8 mm (5/16"), 10 mm (3/8"), and 16 mm (5/8") (verify with manufacturer).
  2. Widths: 75 mm (3") to 178 mm (7") wide (verify with manufacturer).
  3. Lengths: Fixed and random (Refer to grading rules and manufacturer).
  4. Side Edges: Tongue and groove.
  5. Top Face Edges: Eased, bevelled, or square (verify with manufacturer).
  6. Species: Face veneer available in Red and White Oak, Beech, Birch, Hard Maple, Ash, Walnut, and Cherry. Other species are available from some flooring manufacturers.
  7. Grading: In accordance with applicable grading rules for species.
  8. Finish: Factory pre-finished or unfinished for sanding and finishing on site.
  9. Installation: May be loose laid or floated (for engineered flooring with mechanically fastened joints), mechanically fastened (side nailed in tongue or using special "clip" system method) with or without acoustical underlayment or glued down (but any method not directly to concrete) over an acceptable substrate in accordance with manufacturer's recommendations and applicable grading association (e.g. NOFMA) and NFCA requirements.
  10. Availability: Refer to specific manufacturer / supplier.
.08 Engineered Parquet Flooring: This type of flooring consists of small slats or fillets of sawn hardwood as noted herein assembled in units or "tiles" that may consist of individual squares, or units with slats arranged in various patterns, or with slats of same or contrasting species.
  1. Thicknesses: 8 mm (5/16") and 10 mm (3/8").
  2. Slat Sizes: Varies depending on pattern selected.
  3. Unit or Tile Sizes: varies from 100 mm (4") up to 300 mm (12") square but may vary depending on pattern selected. Multiple tiles (usually four depending on size) with a common paper or mesh backing may also be available. Verify with manufacturer.
  4. Side Edges: Square (usually unfinished) or tongue and groove (usually pre-finished) to suit requirements (verify with manufacturer).
  5. Top Face Edges: Usually eased or bevelled (verify with manufacturer).
  6. Species: Available in Red and White Oak. Other species may be available from some manufacturers.
  7. Grading: In accordance with NOFMA official grading rules. Other species (if available) to appropriate grading rules.
  8. Patterns: Typically linear slats but may also be available in other patterns (refer to each manufacturer for variety available).
  9. Finish: Factory pre-finished or unfinished for sanding and finishing on site.
  10. Installation: Typically glued down over an acceptable substrate in accordance with manufacturer's recommendations and applicable grading association (e.g. NOFMA) and NFCA requirements.
  11. Availability: Refer to specific manufacturer / supplier. 
.09 Self-Adhesive Engineered Parquet Flooring: This type of flooring consists of engineered parquet flooring as noted above complete with a self-adhesive (peel and stick) backing. The design authority must verify all requirements (e.g., species, patterns, etc.) and availability of this type of parquet flooring with suppliers before use.
4 • LAMINATE FLOORING
.01 This type of flooring should not be confused with engineered or laminated flooring.

.02 Refer to Part E03C - Material Guide for a description of this type of flooring material.
5 • HARDWOOD SPORTS FLOORING
.01 Flooring: This type of flooring consists of solid hardwood strips on a resilient floor system assembly suitable for gymnasiums, auditoriums, indoor tennis, basketball, handball, squash, and racquet ball courts, stages, and dance / ballet studios. The installation may be permanent or portable (i.e., fully removable).
  1. Thickness: 20 mm (25/32") and 25 mm (33/32") although thickness may vary depending on type of system.
  2. Strip Widths: 38 mm (1-1/2"), 45 mm (1-3/4"), 50 mm (2"), 57 mm (2-1/4"), 83 mm (3-1/4") as recommended by manufacturer for type of system selected.
  3. Strip Lengths: Random for strip pattern, or specified length for parquet patterns.
  4. Side Edges: tongue and groove.
  5. Top Face Edges: square.
  6. Species: typically Northern Hard Maple, except other species may be available.
  7. Grading: In accordance with MFMA, CLA, or other appropriate grading rules and manufacturer's requirements.
  8. Finish: Typically unfinished for site sanding, finishing, and application of game markings, except removal floor systems may be pre-finished in panel form complete with game line markings.
  9. Game Markings: Refer to MFMA guidelines or specific sport association for court layout dimensions, lines, and colours and to flooring distributor for type of durable paint compatible with floor finish to use for line work.
  10. Installation: Over an acceptable substrate in accordance with hardwood sports flooring manufacturer's system assembly recommendations and applicable grading association (e.g. MFMA, NOFMA) and NFCA requirements.
  11. Availability: Refer to specific manufacturer / supplier. 
.02 Sport Flooring System Assemblies: There are a variety of engineered systems used as part of a hardwood sports flooring installation over a concrete of wood floor substrate. These are intended to suit a variety of activities such as court games (basketball, volleyball, badminton, etc.), aerobics, gymnastics, dancing, as well as assembly purposes such as theatre productions, gymnasiums, auditoriums, convention centres, etc. Such systems are designed to meet specific and measurable performance, safety, and comfort criteria such as shock absorption, ball bounce, vertical and area deflection, surface friction, and rolling loads (as well as other design loads for bleachers, backstops, etc.)
The following should be considered for any sports floor installation
  1. Shock Absorption: As an athlete impacts a sports surface the impacting force is translated into two resultant forces, one absorbed by the floor, the other returned to the athlete. Hard surfaces such as concrete and asphalt provide little or no force reduction for the athlete upon impact, due to running, jumping or falling. Sports floor systems absorb these impact forces (shock) and are rated by the percentage of force reduction they provide as compared to hard surfaces.
  2. Vertical and Area Deflection: The measurements of both area and vertical deflection are interdependent. The two together form a criterion for determining the total stability of the floor in the total scheme of performance characteristics. This is called deformation control. This characteristic is a measure of the systems ability to provide vertical deflection for athletes performing in close proximity to each other such as in basketball. Vertical deflection deals with vertical displacement of the flooring surface during impact.
  3. Ball Bounce: This measurement of a basketball's response reflecting (rebounding) off a hardwood sports floor system as compared to its response off a hard surface such as concrete is referred to ball bounce. At 100% rebound, the basketball reflects to a height equal to its response off concrete. This may not apply to all sports activities.
  4. Surface Friction: Often called Sliding coefficient or the coefficient of friction, this characteristic is used to measure the floor's ability to control sliding of athletes on its surface. A sports floor system must have a high surface friction with enough to prevent premature and uncontrollable sliding but low enough to permit sliding if an extreme force is exerted on an athlete such as that caused by two athletes colliding together. Surface friction is a direct function of the finish on the surface and carries equal importance in all activities.
  5. Rolling Loads: Due to the potential damage caused by some maintenance machines, game equipment (backstops, etc.), and furniture (chair dollies, bleachers, high lifts, etc.) designing a flooring system to include for such rolling loads is very important. The pressure of rolling loads caused by rolling equipment and furniture as well as additional provisions to protect the floor should be considered. 
Note: The Design Authority must contact the hardwood sports flooring manufacturer or supplier for types of systems available to meet the necessary performance requirements. Some of these "subfloor systems" include:
  1. Panel system comprising two layers of laminated plywood and resilient pads.
  2. Sleeper system comprising softwood sleepers and resilient pads
  3. Sleeper Subfloor System comprising both of the above systems with one or two layers of plywood.
A variety of components are used in the above assemblies. These may include:
.03 Sports Flooring System Components:
  1. Membrane: Refer to "Underlayments" noted below.
  2. Resilient Pads or Cushion: resilient material with type of material and configuration (individual pads or continuous sheet cushion) in accordance with sport flooring manufacturer's system requirements.
  3. and / or 
    1. Sleepers: continuous kiln dried water repellent preservative treated solid wood (e.g. Douglas Fir) or plywood strips in accordance with sport flooring manufacturer's system requirements. These may also be proprietary metal strips configured to accept resilient pads.
    2. Plywood: Minimum of one layer of 19 mm (3/4") or two layers of 13 mm (1/2") thick x 1200 mm x 2400 mm (48" x 96") exterior grade Douglas Fir plywood. Where two layers are used they shall be nailed together at 45° or 90° angles, unless otherwise required by sports flooring manufacturer.
    3. System Anchoring Devices: Sport flooring manufacturer's proprietary channels and/or adjustable fastener system.
    4. Vent-Cove Base: Solid rubber vented cove base designed to permit ventilation of the void space under flooring and to cover perimeter expansion space. This base is usually available in various colours and is supplied by the sports flooring or a resilient flooring manufacturer or supplier. The design authority should contact the flooring manufacturer or supplier for types and colour range available. Flooring Inserts: Proprietary metal inserts (usually brass) for game equipment (net posts, etc.) and floor outlets (electrical service power outlets and sound system plug-ins / microphone jacks) with the type to suit use requirements and flooring assembly. 
    5. Flooring Inserts: Proprietary metal inserts (usually brass) for game equipment (net posts, etc.) and floor outlets (electrical service power outlets and sound system plug-ins / microphone jacks) with the type to suit use requirements and flooring assembly.
6 • SPECIALTY HARDWOOD FLOORING
.01 Strip Block Flooring: This type of flooring consists of selected kiln-dried edge grain wood blocks that are precision machined on four sides, turned on end (to expose end grain), and assembled with soft aluminium wire splines into flexible strips. Tongue and groove construction is also an option with some manufacturers.
  1. Thicknesses: Nominal 25 mm (1"), 38 mm (1 1/2"), 50 mm (2"), or 65 mm (2-1/2").
  2. Strip Width: 89 mm (3-1/2") to 140 mm (5-1/2").
  3. Strip Length: Random for strip pattern, or specified length for parquet patterns.
  4. Edges: Bottom edges bevelled and backside grooved for surplus mastic.
  5. Patterns: Available in Strip Pattern or Parquet Pattern (right angle).
  6. Species: Available in Douglas Fir, Hemlock, or Alder.
  7. Grading: To flooring manufacturer's standards for specie selected.
  8. Finish: Factory sanded with 40 grit or unfinished for final sanding and finishing on site.
  9. Installation: Glue down installation over an acceptable substrate in accordance with flooring manufacturer's recommendations and applicable grading association (e.g. NOFMA) and NFCA requirements.
  10. Availability: Limited - refer to specific manufacturer / supplier.
Note: this type of "end grain" hardwood flooring is very durable.
.02 Acrylic Impregnated Wood Flooring:
This "pre-finished" type of flooring consists of a hardwood species which has been subjected to an acrylic impregnation process that uniformly dyes and permanently infuses a "built-in" acrylic finish to the hardwood. This process forces an acrylic plastic (methyl-acrylate monomer) into the full cell structure of the wood utilizing a vacuum / pressure cycle. Fire retardant additives may also be included during this impregnation process in order to provide a flame spread rating where required. After the wood is impregnated, the composite is subjected to further treatment to produce high abrasion resistance and hardness.
  1. Thickness: 8 mm (5/16") (verify with acrylic/wood flooring manufacturer or supplier).
  2. Sizes: Various, depending on pattern selection (Design Authority should contact acrylic/wood flooring manufacturer or supplier).
  3. Styles: Available in Strip, Plank, Parquet, Brick, and Tile flooring.
  4. Patterns: Available only in limited patterns (verify with acrylic/wood flooring manufacturer or supplier).
  5. Species: Available in Oak, Ash, Maple, and Walnut, although others may also be available.
  6. Grading: To manufacturer's standard for species selected.
  7. Finish: Factory finished or unfinished for sanding and finishing on site.
  8. Installation: May be loose laid or floated (for engineered flooring with mechanically fastened joints), mechanically fastened (side nailed or stapled in tongue) with or without acoustical underlayment or glued down (but any method not directly to concrete) over an acceptable substrate in accordance with manufacturer's recommendations and applicable grading association (e.g. NOFMA) and NFCA requirements.
  9. Availability: