Green Building Materials

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1 Green Building Materials NSCC - RES 131 Cate O dahl, Instructor Week 3: Envelopes Last Class Assignment Read GreenSpec Guide Structural Systems & Components Sheathing Exterior Finish & Trim Roofing

Review Week Two Site Work / Construction Hardscapes

Foundations, Footers & Slabs Building Material

produces CO 2, which contributes to greenhouse gas

indicator of the overall environmental impact of

2 Review Week Two Site Work / Construction Hardscapes Landscaping Furnishings Green Roofs Decking Foundations, Footers & Slabs Building Material Concepts Embodied Energy Energy consumption produces CO 2, which contributes to greenhouse gas emissions, so embodied energy is considered an indicator of the overall environmental impact of building materials and systems

3 Building Material Concepts Embodied Energy Embodied energy is the energy consumed by all of the processes associated with the production of a building, from the mining and processing of natural resources to manufacturing, transport and product delivery. Embodied energy does not include the operation and disposal of the building material, which would be considered in a life cycle approach. Building Material Concepts Cradle-To-Cradle Life Cycle Assessment Life Cycle Assessment (LCA) is a tool for the systematic evaluation of the environmental aspects of a product or service system through all stages of its life cycle. (United Nations Environment Program, LCA provides an adequate instrument for environmental decision making.

Thermal Bridges are junctions where insulation is not continuous, allowing for heat loss.

4 House as a System When evaluating Structural Systems & Components, it s best to consider the house as a system Consider how air flows into and out of the house Build/Seal it Tight, Ventilate Right Heat flows from areas of high temp to low temp Thermal Bridging vs Thermal Break Thermal Bridges are junctions where insulation is not continuous, allowing for heat loss. A Thermal Break or thermal barrier is an element of low thermal conductivity (insulation) placed in an assembly to reduce or prevent the flow of thermal energy between conductive materials

REDUCED THERMAL BRIDGING Advanced Framing or Optimal Value Engineering Advanced Framing is defined as studs framed on 24-inch centers with double top plate and single bottom plate.

5 REDUCED THERMAL BRIDGING Advanced Framing or Optimal Value Engineering Advanced Framing is defined as studs framed on 24-inch centers with double top plate and single bottom plate. Corners use two studs or other means of fully insulating corners and one stud is used to support each header. Headers consist of double 2x material with R-10 insulation between the header and exterior sheathing. From WSEC Builders Field Guide Reduced Thermal Bridging Courtesy of US Dept. Of Energy

6 Week 3 Overview The Building Envelope Structural Systems & Components Sheathing Exterior Finish & Trim Roofing Structural Components Wood is most common framing material Engineered Lumber Reclaimed Lumber Metal Framing Concrete/Masonry SIPs / Foam Panels Other Alternatives

7 Did you know? When considered over a building s lifetime from harvest of raw materials through manufacturing, transportation, installation, use, maintenance and disposal or recycling wood performs better than concrete and steel in terms of embodied energy, air and water pollution, carbon footprint and global warming potential. Engineered Lumber Uses smaller diameter, young trees to create long span beams to replace virgin sawn lumber Uses low grade trees processed into long strands Uses veneers of faster growing, young, lower grade species, in parallel lamination (similar to plywood) Uses almost the entire tree with as little as 25 year planting rotations Water proof binders are used Replaces the need for old growth timbers High load capacity and span capability

Engineered Lumber Structural Components Examples Glulam Beams Structural Glued Laminated Timber lumber is joined end to end and face to face bonded for lengths over 60 feet and depths over 30 inches

50% of LVL production goes to I Joist flanges Structural Composite Lumber LSL - Laminated Strand Lumber PSL - Parallel Strand Lumber OSB - Oriented Strand Board Uses rims, headers, studs, columns,

8 Engineered Lumber Structural Components Examples Glulam Beams Structural Glued Laminated Timber lumber is joined end to end and face to face bonded for lengths over 60 feet and depths over 30 inches used as vertical columns or horizontal beams Structural Composite Lumber LVL s Laminated Veneer Lumber Uses: rims, headers, and flange material for I Joists 35% more efficient use than sawn lumber 50% of LVL production goes to I Joist flanges Structural Composite Lumber LSL - Laminated Strand Lumber PSL - Parallel Strand Lumber OSB - Oriented Strand Board Uses rims, headers, studs, columns, sheeting Also used as the web of I Joists Cross-laminated timber Cross laminated timber or CLT is a form of engineered wood that allows architects and designers to build taller buildings and use CLT as a structural material for new construction and existing buildings New Product in the US advanced product designed for increased dimensional stability and strength in framing systems. made of multiple layers of wood, with each layer oriented crosswise to the next. Used for long spans in floors, walls or roofs, CLT can be prefinished, which reduces labor onsite, and is equally suited to new construction and additions to existing buildings.

CLT in Seattle Cascade Built has been selected to build a new single family home Located in the heart of Madison Park on a triangular infill lot, the unique

3bd/2ba Features a stunning cantilevered second story to provide space for the groundlevel carport, a rooftop terrace with neighborhood views and built-in planters

Sustainable elements include beautiful site salvaged woodwork planned for the stair treads and dining table heat recovery ventilator (HRV) to filter toxins and

9 CLT in Seattle Cascade Built has been selected to build a new single family home Located in the heart of Madison Park on a triangular infill lot, the unique 1,485sf single-family home maximizes its site with bold 45 degree corners and strong vertical lines. 3bd/2ba Features a stunning cantilevered second story to provide space for the groundlevel carport, a rooftop terrace with neighborhood views and built-in planters for urban gardening. Sustainable elements include beautiful site salvaged woodwork planned for the stair treads and dining table heat recovery ventilator (HRV) to filter toxins and allergens from outdoor air zero VOC finishes. The home will meet BUILT GREEN 4-Star. Construction is scheduled for completion Spring of Reclaimed Lumber Returns beams, studs and columns to high use service Re milled as flooring, millwork, etc. Mostly old growth, very desirable quality of wood Reduces demand on virgin timber and reduces landfill Cradle to cradle reuse!

Forest Stewardship Council Certified Lumber Certified Sustainably Forested Wood Why FSC certification?

biodiversity of the forest floor Promotes the economic and social viability of indigenous people throughout the world The

Steel Framing 20 90% post consumer recycled content Recyclable at the end of building s life Fireproof, insect proof, stable

10 Forest Stewardship Council Certified Lumber Certified Sustainably Forested Wood Why FSC certification? Protects from clear-cut deforestation through selective harvesting Enforces harvesting practices that promotes the health and biodiversity of the forest floor Promotes the economic and social viability of indigenous people throughout the world The only forest certification system that is supported by all major environmental groups Metal Framing Light Gauge, Cold Rolled Steel Framing 20 90% post consumer recycled content Recyclable at the end of building s life Fireproof, insect proof, stable and light weight Thermal conductivity creates challenges for insulation strategies High embodied energy to produce Photos Courtesy of The Steel Network

ICFs: Insulated Concrete Forms Interlocking modular

filled with concrete www.amvicsystem.com www.

com SIPS: Structural Insulated Panels Manufacturer

energy used to create the EPS core in the first

11 ICFs: Insulated Concrete Forms Interlocking modular units that are dry-stacked (without mortar) and filled with concrete SIPS: Structural Insulated Panels Manufacturer s suggest that a sips house will save 19X the energy used to create the EPS core in the first year No longer filled with ozone depleting HCFC Resource efficient OSB panels made of weed trees Thanks to Insulspan

labor and weather exposure Recent improvements in mold and termite control

12 SIPS: Pre-Manufactured Panelized Construction Minimized waste through computer controlled panel production Fast installation time reduces field labor and weather exposure Recent improvements in mold and termite control Thanks to Insulspan SIPS: Effective Thermal Resistance Comparison Thanks to Insulspan

REGIONAL MATERIALS Straw Bale Straw Bale by

Rammed Earth by SIREWALL Sheathing Uses:

substrate for attaching finish layer often

Materials Plywood OSB Recycled Content options

13 REGIONAL MATERIALS Straw Bale Straw Bale by Living Shelter Design Rammed Earth Adobe Block Rammed Earth by SIREWALL Sheathing Uses: secondary weather barrier can be primary substrate for attaching finish layer often provides diagonal bracing for structure Common Materials Plywood OSB Recycled Content options Aluminum foil facing over recycled paperboard Exterior gypsum

SHEATHING PLYWOOD Made by peeling a spinning log into layers called veneers Veneers are glued together with opposing grain directions, then baked in a press Superior strength and

Thin flakes or strands shaved from fast growing, small, weed trees like POPLAR and ASPEN.

14 SHEATHING PLYWOOD Made by peeling a spinning log into layers called veneers Veneers are glued together with opposing grain directions, then baked in a press Superior strength and stability Maximizes use of the log Binder glues commonly uses formaldehyde resin, but more formaldehyde free available now Available with FSC wood SHEATHING OSB - Oriented Strand Board Thin flakes or strands shaved from fast growing, small, weed trees like POPLAR and ASPEN. Strands are oriented on a massive conveyor belt, coated with resins and wax, then placed in a thermal press Efficient use of the tree Concerns over binders, but many now available w/ non formaldehyde MDI resins Concerns over mold growth, but many now treated. Does not handle exposure well.

Typical roofing materials absorbs Sun s heat, then radiates it throughout the attic Oak Ridge National Labs

15 SHEATHING Radiant Barrier Ply s and OSB Simple plywood or OSB with a reflective foil facing. Low emissivity or Low e facings, like aluminum foil, reflect heat, the inverse of radiating heat. Typical roofing materials absorbs Sun s heat, then radiates it throughout the attic Oak Ridge National Labs claim a 15 40% reduction in summer heat gain Photo from Fine Homebuilding Taunton Press 1/07 Insulated Panels and Rigid Foam Photo: Pactiv Products

Pre-Manufactured Shearwall High strength resists wind and seismic lateral forces Same end

that carry load from above, like garage walls Cons: Non FSC wood, OSB Source: Simpson

seismic conditions dictate engineering strategies.

Homes that have been retrofitted with structural wood panels and metal seismic hold downs

16 Pre-Manufactured Shearwall High strength resists wind and seismic lateral forces Same end result as a field built wall with less field labor and waste Uses include short walls that carry load from above, like garage walls Cons: Non FSC wood, OSB Source: Simpson Strong Tie Regional Strategies Sheathing and Metal Connectors Regional weather and seismic conditions dictate engineering strategies. Many regions require special engineering to withstand the forces of nature. Homes that have been retrofitted with structural wood panels and metal seismic hold downs could withstand a major earthquake with only minor structural damage. This home was destroyed because of inadequate cripple wall construction. Photo: USGS

shear panels) to counter the effects of lateral load acting on a structure.

17 What s the purpose of Sheating, Shear Walls, and Metal Fasteners? They contribute to the durability of the structure against natural forces. Sheathing often provides diagonal bracing In structural engineering, a shear wall is a structural system composed of braced panels (also known as shear panels) to counter the effects of lateral load acting on a structure. Wind and seismic loads are the most common loads that shear walls are designed to carry. Metal fasteners tie the component to the structure Photo: BuilderOn Line.com Natural Forces Earthquake Hazard Map Map by USGS Courtesy of Mapwatch

18 Natural Forces Tornado Hazard Map Source: NOAA Natural Forces Hurricane Hazard Map Source: USGS

com Structural wood panels installed on cripple walls @ #210 Elm St. days before a 7.9 mag. earthquake.

19 Earthquake Retrofits Sheathing and Metal Connectors 1989 Santa Cruz Unexpected Retrofit Experiment Typical pony wall failure. Entirely avoidable similar to Santa Cruz control house. #214 Elm St. w/ no cripple wall retrofit Total Repairs= #260,000 Photo: EarthquakeAdvisor.com Structural wood panels installed on cripple #210 Elm St. days before a 7.9 mag. earthquake. Total repairs= $5000 Photo: National Park Service Envelope Strategies EXTERIOR CLADDING Rainscreens Principles and Components Airspace/ Drainage Plain Options Rigid Foam Thermal Breaks Cladding/ Finish Siding

Rainscreens SIMPLE PRINCIPLE Diminish the forces that drive water into walls Equalizes Air and Wind Pressure that drives water behind cladding Provides for Drainage Plane Dries out water driven

20 Rainscreens SIMPLE PRINCIPLE Diminish the forces that drive water into walls Equalizes Air and Wind Pressure that drives water behind cladding Provides for Drainage Plane Dries out water driven behind the cladding by wind pressure Envelope Strategies Airspace /Drainage Plain Options Simple principle Cladding is held away from the wall to create a continuous air space from the bottom plate to the eaves. Acts as a drainage plane, to allow cladding to dry. With larger spaces (3/4 2 ) also equalizes pressure (referred to as a PERS). Strips of wood, metal, or composite secured to the structure of building, through the foam and moisture/air barrier, with long fasteners. Must be vertical. Special attention required at penetrations. Wood strips can be treated wood, treated ply, primed wood from salvage, reclaimed siding cut into strips, etc. (assumes the material is a weather resistant hardy material) Metal and composites typically part of a manufacturers rainscreen cladding package mostly commercial Integrated drainage plane products also available

Envelope Strategies Drainage Plain Membranes Home Slicker

Polyisocyanurate Closed-cell foam filled with

Highest r-value, higher burn temperature, higher density,

foam, processed polystyrene crystals w/ blowing agent,

density, no thermal drift Extruded Polystyrene - (XPS)

21 Envelope Strategies Drainage Plain Membranes Home Slicker Pactiv Envelope Strategies RIGID FOAM THERMAL BREAK Polyisocyanurate Closed-cell foam filled with low-conductive gas as blowing agent. Highest r-value, higher burn temperature, higher density, note thermal drift Expanded Polystyrene - (EPS) Closed-cell foam, processed polystyrene crystals w/ blowing agent, cheaper, lower r-value, lower burn temperature, lower density, no thermal drift Extruded Polystyrene - (XPS) Extruded version of EPS, more water resistant, better r-value, lower burn temperatures, low density, no thermal drift

Look for it at Martha Rose s new project Indian Wall February 28th Flashing Important wall assembly

entering between gaps in adjoining building surfaces.

22 Envelope Strategies New Product Thermacork Brand new product combine the beauty and elegance of cork and all of it s insulating powers. Look for it at Martha Rose s new project Indian Wall February 28th Flashing Important wall assembly component Window flashing is material installed around windows designed to prevent water from entering between gaps in adjoining building surfaces. Wind-driven rainwater can enter even small spaces left between the frame, or casing, of a window and the siding, or trim, of the home. A lack of properly installed flashing can lead to water infiltration to inner walls that can cause wood rot and structural damage as well as insect infestation. This product is available in three basic types: sheet metal, vinyl, and tape www. wisegeek.com/what-is-window-flashing.htm

Cladding/ Finish Siding Fiber Cement-Lap, panels and shingles Durable, low-maintenance, holds paint cementitious Composition-Lap and Panels Uses recycled wood fiber concerns over durability and water

Stone Masonry Lasts forever, uses natural resources, high embodied energy Cultured (cast) stone masonry Affordable, real looking, concerns over long-term durability Standing seam metal Durable,

23 Cladding/ Finish Siding Fiber Cement-Lap, panels and shingles Durable, low-maintenance, holds paint cementitious Composition-Lap and Panels Uses recycled wood fiber concerns over durability and water FSC Wood- Lap and shingles Cedar and pre-primed, limited supply, requires maintenance Reclaimed wood Lap and shingles, trim Limited supply, requires reconditioning, requires maintenance Brick and Stone Masonry Lasts forever, uses natural resources, high embodied energy Cultured (cast) stone masonry Affordable, real looking, concerns over long-term durability Standing seam metal Durable, low-maintenance, pre-painted, high embodied energy Roofing Products Composition Shingles Inexpensive, asphalt based, heat sink re roof every yrs Architectural Composition Laminated Same as above, thicker, more plys = 30,40 and 50 yr lifespan Cedar Shake Cedar, burns easily, requires maintenance, bad use of wood? Metal, Standing Seam Metal Durable, low maintenance, pre painted, 50 yr + lifespan Rolled Asphalt roofing Black surface = heat sink, high embodied energy, yrs Torch Down Similar to above, but requires fire to apply yrs Thermoplastics PVC Chlorine content, phthalate plasticizers, potential dioxin production in a fire PVC production has many environmental issues

24 Roofing Products TPO Thermoplastic Olefin Membranes White, single ply membrane reflects the sun Reduces cooling loads due to a cooler ceiling No chlorine, phthalates, non halogenated Air heat welded Roofing Products Vegetated Roof

Increase life of roofing material Reduces storm run off Purifies water

25 Roofing Products Vegetated Roof Grow fruits, vegetable, herbs, flowers Reduces home heating and cooling Reduces urban heat island effect Increase life of roofing material Reduces storm run off Purifies water through planting medium Filters CO2 and pollutants from the air Is incredibly beautiful!

Framing Methods Structural Components

Framing Methods Structural Components Balloon Framing *Balloon framing or Eastern framing the exterior studs run from the top of the foundation to the top of the highest level. Benefits of this type of