> For the complete documentation index, see [llms.txt](https://docs.betterbuilding.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.betterbuilding.io/support-and-training/other-support/platform-generic-material-data/timber.md). # Timber ## Engineered Wood Products & Solid Wood ### Cross Laminated Timber Cross Laminated Timber (CLT) is an engineered wood product manufactured by laminating multiple layers of solid sawn lumber or engineered lumber in alternating perpendicular directions. This cross-lamination creates a dimensionally stable, high-strength structural panel suitable for a wide range of applications in construction. #### **Basic Information** | Property | Value | | -------------------- | ------------------------------------------------------------ | | Type | Engineered Wood / Structural Panel | | Thickness (m) | 0.135 | | Thickness (mm) | 135.0 | | Colour | Dark Blue | | Primary Applications | Structural framing, floor systems, wall panels, roof decking | #### **Thermal Properties** | Property | Metric | Imperial | | ---------------------------- | --------------- | ---------------------- | | Thermal Conductivity | 0.098 W/(m·K) | 0.57 BTU·in/(h·ft²·°F) | | Specific Heat Capacity | 1300 J/(kg·K) | 0.31 BTU/(lb·°F) | | Density | 410 kg/m³ | 25.6 lb/ft³ | | Thermal Resistance (R-value) | 1.377 m²·K/W | 7.82 ft²·°F·h/BTU | | Heat Capacity (per m²) | 13.65 kJ/(m²·K) | 2.40 BTU/(ft²·°F) | #### **Vapour Properties** | Property | Value | | -------------------------------------------- | ---------------------- | | Water Vapour Diffusion Resistance Factor (µ) | 500.0 | | Equivalent Air Layer Thickness (sd-value) | 67.5 m | | Vapor Resistivity | 2500.00 MNs/gm | | Vapor Resistance | 337.50 MN.s/g | | Classification | Class I Vapor Retarder | *** ### Oriented Strand Board (OSB) Oriented Strand Board combines wood strands bonded with phenol-formaldehyde resin in layers oriented perpendicular to provide strength in multiple directions. Typical applications include structural sheathing, subflooring, wall bracing, and roof decking. 12.5mm thickness represents 1/2" standard sheathing. High µ-value of 812.8 provides significant vapor barrier function requiring ventilation design. Suitable for exterior applications when protected with proper drainage plane. Cost-effective alternative to plywood with similar structural performance. Moisture content affects dimensional stability and thermal properties. Requires edge sealing in wet applications. #### **Basic Information** | Property | Value | | -------------------- | ------------------------------------------------------------- | | Type | Engineered Wood / Structural Sheathing | | Thickness (m) | 0.0125 | | Thickness (mm) | 12.5 | | Thickness (inches) | 0.492" | | Colour | Natural Wood / Tan | | Primary Applications | Structural sheathing, subflooring, wall bracing, roof decking | #### **Thermal Properties** | Property | Metric | Imperial | | ---------------------------- | --------------- | ---------------------- | | Thermal Conductivity | 0.092 W/(m·K) | 0.53 BTU·in/(h·ft²·°F) | | Specific Heat Capacity | 1880 J/(kg·K) | 0.45 BTU/(lb·°F) | | Density | 650 kg/m³ | 40.6 lb/ft³ | | Thermal Resistance (R-value) | 0.14 m²·K/W | 0.79 ft²·°F·h/BTU | | Heat Capacity (per m²) | 15.31 kJ/(m²·K) | 2.69 BTU/(ft²·°F) | #### **Vapour Properties** | Property | Value | | -------------------------------------------- | ----------------------- | | Water Vapour Diffusion Resistance Factor (µ) | 812.8 | | sd-value | 10.16 m | | Vapor Resistivity | 4064.00 MNs/gm | | Vapor Resistance | 50.80 MN.s/g | | Perm Rating | 0.07 perms | | Classification | Class II Vapor Retarder | *** ### Plywood Plywood consists of cross-laminated veneers bonded with phenol-formaldehyde or urea-formaldehyde resin providing strength and stability in multiple directions. 10mm thickness represents 3/8" standard sheathing. Lower µ-value of 274 compared to OSB allows slightly more vapor transmission. Suitable for structural sheathing, subflooring, and interior applications. Vapor permeability varies by veneer orientation and adhesive type. Superior strength-to-weight ratio compared to solid wood. Moisture absorption requires protection from prolonged wetting. Excellent dimensional stability when properly acclimated. #### **Basic Information** | Property | Value | | -------------------- | ------------------------------------------------------------- | | Type | Engineered Wood / Sheathing | | Thickness (m) | 0.010 | | Thickness (mm) | 10.0 | | Thickness (inches) | 0.394" | | Colour | Natural Wood / Tan | | Primary Applications | Structural sheathing, subflooring, wall bracing, roof decking | #### **Thermal Properties** | Property | Metric | Imperial | | ---------------------------- | --------------- | ---------------------- | | Thermal Conductivity | 0.15 W/(m·K) | 0.87 BTU·in/(h·ft²·°F) | | Specific Heat Capacity | 1500 J/(kg·K) | 0.36 BTU/(lb·°F) | | Density | 700 kg/m³ | 43.7 lb/ft³ | | Thermal Resistance (R-value) | 0.07 m²·K/W | 0.38 ft²·°F·h/BTU | | Heat Capacity (per m²) | 10.50 kJ/(m²·K) | 1.85 BTU/(ft²·°F) | #### **Vapour Properties** | Property | Value | | -------------------------------------------- | ----------------------- | | Water Vapour Diffusion Resistance Factor (µ) | 274.0 | | sd-value | 2.74 m | | Vapor Resistivity | 1370.00 MNs/gm | | Vapor Resistance | 13.70 MN.s/g | | Perm Rating | 0.22 perms | | Classification | Class II Vapor Retarder | *** ### Softwood Softwood represents solid lumber from coniferous species (pine, fir, spruce) used for structural and finish applications. Typical thickness 19mm represents 3/4" standard board. Lower density of 400 kg/m³ provides moderate insulation value. The µ-value of 200 provides moderate vapor resistance suitable for breathable construction. Strength properties vary by species, grade, and moisture content. Moisture content 6-9% recommended for interior use. Dimensional stability affected by moisture changes requiring proper acclimation. Excellent workability and availability. Common structural member in residential construction. #### **Basic Information** | Property | Value | | -------------------- | ------------------------------------------------------------ | | Type | Solid Wood / Structural Lumber | | Thickness (m) | 0.019 | | Thickness (mm) | 19.0 | | Thickness (inches) | 0.748" | | Colour | Yellow, Light Brown | | Primary Applications | Structural framing, cladding, finish carpentry, roof decking | #### **Thermal Properties** | Property | Metric | Imperial | | ---------------------------- | --------------- | ---------------------- | | Thermal Conductivity | 0.09 W/(m·K) | 0.52 BTU·in/(h·ft²·°F) | | Specific Heat Capacity | 1400 J/(kg·K) | 0.33 BTU/(lb·°F) | | Density | 400 kg/m³ | 25.0 lb/ft³ | | Thermal Resistance (R-value) | 0.21 m²·K/W | 1.20 ft²·°F·h/BTU | | Heat Capacity (per m²) | 10.64 kJ/(m²·K) | 1.87 BTU/(ft²·°F) | #### **Vapour Properties** | Property | Value | | -------------------------------------------- | ----------------------- | | Water Vapour Diffusion Resistance Factor (µ) | 200.0 | | sd-value | 3.8 m | | Vapor Resistivity | 1000.00 MNs/gm | | Vapor Resistance | 19.00 MN.s/g | | Perm Rating | 0.30 perms | | Classification | Class II Vapor Retarder | *** ### Hardwood Hardwood represents solid lumber from deciduous species (oak, maple, walnut) used primarily for finish and specialty applications. Typical thickness 19mm represents 3/4" standard flooring or board. Higher density of 650 kg/m³ compared to softwood provides greater thermal mass. The µ-value of 200 matches softwood for moderate vapor resistance. Excellent durability and aesthetic qualities. Moisture content 6-9% recommended for interior use. Dimensional stability better than softwood but still affected by moisture. Premium cost limits structural applications. Superior workability and finish quality. Superior strength and hardness properties. #### **Basic Information** | Property | Value | | -------------------- | ------------------------------------------------------ | | Type | Solid Wood / Flooring & Specialty | | Thickness (m) | 0.019 | | Thickness (mm) | 19.0 | | Thickness (inches) | 0.748" | | Colour | Variable (Oak, Walnut, Maple, etc.) | | Primary Applications | Flooring, cladding, structural beams, finish carpentry | #### **Thermal Properties** | Property | Metric | Imperial | | ---------------------------- | --------------- | ---------------------- | | Thermal Conductivity | 0.13 W/(m·K) | 0.75 BTU·in/(h·ft²·°F) | | Specific Heat Capacity | 1400 J/(kg·K) | 0.33 BTU/(lb·°F) | | Density | 650 kg/m³ | 40.6 lb/ft³ | | Thermal Resistance (R-value) | 0.15 m²·K/W | 0.83 ft²·°F·h/BTU | | Heat Capacity (per m²) | 17.33 kJ/(m²·K) | 3.05 BTU/(ft²·°F) | #### **Vapour Properties** | Property | Value | | -------------------------------------------- | ----------------------- | | Water Vapour Diffusion Resistance Factor (µ) | 200.0 | | sd-value | 3.8 m | | Vapor Resistivity | 1000.00 MNs/gm | | Vapor Resistance | 19.00 MN.s/g | | Perm Rating | 0.30 perms | | Classification | Class II Vapor Retarder | *** ## Natural & Bio-based Insulation ### Cork Cork represents renewable material harvested from cork oak bark without harming the tree. Typical thickness 60mm represents underlayment or mid-layer insulation applications. Extremely low µ-value of 10 provides excellent vapor permeability suitable for vapor-open systems. Excellent thermal insulation with conductivity 0.043 W/(m·K) among lowest of natural materials. Elastic recovery >90% after compression. Biodegradable and compostable. Superior acoustic absorption 250-2000 Hz. Non-toxic with no off-gassing. FSC certification ensures sustainable sourcing. Flame resistance class B-s1,d0 in European standards. Minimal embodied carbon compared to synthetic insulation. #### **Basic Information** | Property | Value | | -------------------- | ----------------------------------------------------------------------------- | | Type | Natural Insulation / Bio-based | | Thickness (m) | 0.060 | | Thickness (mm) | 60.0 | | Thickness (inches) | 2.362" | | Colour | Light to Medium Brown | | Primary Applications | Floor underlayment, thermal insulation, acoustic damping, vibration isolation | #### **Thermal Properties** | Property | Metric | Imperial | | ---------------------------- | --------------- | ---------------------- | | Thermal Conductivity | 0.043 W/(m·K) | 0.25 BTU·in/(h·ft²·°F) | | Specific Heat Capacity | 1560 J/(kg·K) | 0.37 BTU/(lb·°F) | | Density | 160 kg/m³ | 10.0 lb/ft³ | | Thermal Resistance (R-value) | 1.40 m²·K/W | 7.95 ft²·°F·h/BTU | | Heat Capacity (per m²) | 14.98 kJ/(m²·K) | 2.64 BTU/(ft²·°F) | #### **Vapour Properties** | Property | Value | | -------------------------------------------- | ---------------------------- | | Water Vapour Diffusion Resistance Factor (µ) | 10.0 | | sd-value | 0.6 m | | Vapor Resistivity | 50.00 MNs/gm | | Vapor Resistance | 3.00 MN.s/g | | Perm Rating | 5.90 perms | | Classification | Class III (Highly Permeable) | --- # Agent Instructions This documentation is published with GitBook. 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