Building to meet the stringent requirements of the seven Petals of the Living Building Challenge has been an eye-opening and educational experience for all involved with the Desert Rain project. While each petal has presented challenges, the Materials Petal has had a tremendous impact on time and research. According to the Living Building Challenge, the intent of the material petal is to promote a ‘successful materials economy that is non-toxic, transparent and socially acceptable’. The LBC requires that every material or product used in the project is carefully scrutinized for distance from the source to the site, quality, durability and longevity, aesthetic appeal and beauty, energy efficiency, and effects on health. These considerations are applied to each level of the process from raw material extraction, to manufacturing, to installation, and use. In addition, labor practices at all phases of material production must be acceptable.
The rigorous process of tracking and approving materials for Desert Rain is the work of ML Vidas, a sustainable architect and the LBC/LEED consultant. ML collaborates with the designers, builders, owners, and Living Building Challenge staff to arrive at approved or denied status for each item. She has an extensive spread- sheet of the materials that have been considered, approved, denied or pending. Each product must meet the intent of the Materials Petal and the imperatives and must not contain any of the 14 materials/chemicals that are on the Red List.
Embodied Carbon Footprint
Keeping all that in mind as I walk through the Desert Rain site – it is mind-boggling to think that every component of construction has undergone this approval process. Each material element can be a complex story. For example, the house is wrapped in a weather barrier called Hydro-Tex. Parr Lumber in Bend is the local supplier for the material that is made by a family owned company – Fortifiber Building Systems Corporation in Fernley, Nevada. As a product, Hydro-TEX falls within the LBC/LEED requirements. It is comprised of 22% post consumer waste. It does not contain any of the Red List materials or chemicals. It enhances the durability of the structure, reduces maintenance, and helps to minimize energy consumption. It is manufactured within 500 miles of the project site. Fortifiber actively works at improving their products and their facilities to raise the bar on sustainable standards. Those are the kind of details that must be researched for every material used in the construction of Desert Rain.
Concrete is a major element visible on the project site. The aggregate for the concrete footings, foundation, and cistern, is sourced through a local Bend company, Hooker Creek. The cement and fly-ash originated in Portland. Fly-ash is a byproduct of the coal industry. It was used in the house foundation but not the cistern. The cement slab floor in the main house had the addition of crushed lava rock, recycled from the cistern excavation process. The slab was then polished creating a beautiful finished floor without using any additional building materials or resources. Concrete forms were re-used lumber and timbers.
Empire Stone and Willamette Graystone in Bend are the source for masonry lava rock, landscape gravel, boulders, and pavers. Other rock to be used for landscaping was reclaimed from the on- site deconstruction. This includes broken sidewalk pieces that will be used as pavers for a patio on the north side of the house. LBC highly suggests using as much material as possible from the home site; eliminating waste, transport, and the use of new resources.
All lumber used on the project must be either reclaimed or Forest Stewardship Council Certified. All framing lumber, interior and exterior is FSC. Wood sheathing was one of the items that received a ‘temporary exception’ status. The added formaldehyde in the composite wood products, is a Red List item. Sustainable Northwest Wood based in Portland worked with the builders and Parr lumber to find FSC lumber harvested within the 600 mile zone. Siding is FSC cedar. The exterior soffits are covered with reclaimed lumber from on-site deconstruction and from a potato barn in Prineville. The lumber was re-milled. Re-claimed lumber will also be used on the interior ceilings and some of the interior walls. American made nails were used in the framing instead of the commonly used, made in China nails.
River Roofing of Bend provided sources for the metal roofing, fascia, and belly- band that was coated with a LBC approved coating. The roofing steel arrived in a continuous roll from Kalama, Washington. River Roofing crew fabricated the panels on site. Jim Fagan, builder with Timberline Construction, said, ‘Steel is one of the things that LBC refers to as globally sourced. There is a lot of recycled content in almost all steel now – there is no virgin steel. Obviously, if we can buy a coil of steel from somewhere in the Northwest, we’re going to stay close.” River Roofing also supplied the two-part gutter system. There is a stainless steel gutter set inside the coated steel gutter. The stainless steel was used for its durability, longevity, and resistance to residue build-up since the gutters will be collecting rainwater for domestic use, including drinking water.
Local sub-contractors were also the suppliers of many of the construction elements. They did the research to find appropriate materials from local and regional sources. The solar thermal system was supplied by Bobcat and Sun Inc. in Bend. The photovoltaic modules installed by E2 Solar were sourced from, Solar World Oregon, a company in Hillsboro, Oregon. The general rule of LBC guidelines is the larger and heavier the material, the closer the source should be to the project site. The Loewen windows were an exception to this rule. Though they were supplied through Glacier Windows and Doors in Sweet Home, Oregon, they were manufactured in Manitoba, Canada. The extended distance was balanced by the superior quality and energy efficiency of these windows.
Canada was also the source for the LED lighting cannisters. All Phase Electric Service in Bend is the supplier of all electrical wiring, conduit, outlet and switch boxes. Finding non-PVC plumbing pipe and fittings was quite a challenge. PEX and BPEX tubing from Uponorpro were used for the hydronic, infloor heating system and water lines. All insulation materials were supplied by Energy Conservation Insulation in Bend from a variety of manufacturers. Some of the spray foam insulation contains Halgenated Flame Retardant, a Red List chemical. The approval for use required a LBC exception and a letter to the manufacturer advocating alternatives for the future.
With so many material elements comprising the Desert Rain project, I have shared only a small portion of the depth and detail that is required for this LBC process. Some of the stories are still unfolding. The structures are currently being prepped and tented to receive the exterior lime plaster. Elite Plastering in Bend is a family owned business committed to learning and growing toward a more sustainable built environment. Coming on board with the Desert Rain project, David Kaiser Jr. developed a non-toxic, lime based plaster recipe to cover the exterior walls of the structures. All of the materials in the mix are available very close to home – lime from Washington, clay from Prineville, and pumice right in our backyard, a few miles south of Bend. Lime absorbs carbon monoxide from the atmosphere to chemically change it into limestone, it is durable and will last for decades. The plaster significantly demonstrates a successful story of meeting the imperatives of the Materials Petal.
Part of the Living Building Challenge goal is to create catalysts of change among the owners, builders, sub-contractors and suppliers. They want each project to ‘figure it out’. The Desert Rain team is on the ‘bleeding edge’ of this goal; doing their due diligence, pioneering, researching, creating, to meet the challenge of a sustainable, built environment.