The Cottage Company proves the feasibility of sustainable city living with a nine-unit community.
The idea of living close to a large city has developed something of a negative reputation in recent years, with many a stereotype existing of cramped, noisy, poorly maintained apartments and townhouses.
Thornton Creek Commons, a two-and-a-half-acre development in Seattle, is providing an impressive counterexample, with nine units that are environmentally friendly, conveniently located, cost-efficient and aesthetically pleasing.
Located just north of the University of Washington, Thornton Creek Commons was initially the home of the 1959-era St. George Episcopal Church, which closed in 2016 when declining membership prompted its congregation to merge with that of another church nearby.
The church structure, while initially something the development team at The Cottage Company expected to have to remove completely, proved to be a blessing in disguise (no pun intended).
From the Judges: “Beautiful integration with the local neighborhood.”
“Initially, we believed that we would demolish the 8,000-square-foot church structure,” developer Linda Pruitt recalls. “Mitigation prior to demo exposed the extensive old growth, clear wood paneling, subfloors, framing materials, hand-split old growth cedar siding, and large beams—all that could be used in the construction of the new Thornton Creek Commons community.”
With the help of the Sledge Seattle deconstruction firm, The Cottage Company salvaged 90 percent of the original church structure. The recovered cedar siding became siding for each unit’s detached garages; 4,000 square feet of 3.5-inch, double T&G car decking was milled into solid wood flooring, installed and finished in four of the nine units; and pieces of deconstructed lumber were used throughout the homes to provide aesthetic details and supportive improvements.
Environmental Efficiency
As for the homes themselves, Thornton Creek Commons is a hallmark of sustainable practices and energy efficiency. Each unit is highly insulated, thanks to a combination of mineral wood and wool, blown-in cellulose, foam, fiberglass, and the Brown in Blanket System (BIBS) on every north wall, which provides a greater depth of insulating material, a higher R value, and a complete absence of air gaps between pieces of fiberglass.
The homes’ James Hardie siding is fortified with an Aero Barrier sealant and a rain screen underneath, ensuring that the moisture for which the Puget Sound is known never seeps into the homes. A continuously operating Panasonic Energy Recovery Ventilator (ERV) and Rheem heat pump water heater ensure clean and efficient air and water in the home, while Mitsubishi mini-split heat pumps with external compressors and PEAD interior units keep each unit comfortable and quiet.
The homes’ location was an environmentally conscious decision. Just three blocks from the Lake City urban village core, Thornton Creek Commons is less than a 10-minute walk away from grocery stores, banks, the post office, restaurants, and the local library. The nearby Link light rail station allows residents to get nearly anywhere they need in the city, all without the use of a car.
Thornton Creek Commons also includes recreational space to take advantage of the area’s natural beauty and proximity to the eponymous Thornton Creek, including an off-leash dog park, fire pit, and gardens, as well as dedicated access to northeastern Seattle’s largest flowing watershed.
Like any project, construction of Thornton Creek Commons was not without difficulties. While the Diocese of Olympia, the owners of the original property, was regularly supportive of The Cottage Company’s efforts (and had approached the company with the project to begin with), the city of Seattle itself was less than helpful.
The property was surrounded by existing, already-built single-family homes, Pruitt notes. But it was completely undeserved by sufficient public infrastructure. This necessitated the installation of new public water supply connections and public system improvements, new public sewer connections, new public stormwater connections and onsite stormwater detention and mitigation improvements, and new electric transformer installation and connections.
All of this, plus the required public improvements, had to be paid by the private development—and only the private development—at large expense. “This is one of the key contributors to the high cost of new home construction, making new single-family homes unaffordable to many,” Pruitt says.
Nonetheless, construction continued, and the results were worth it, according to Pruitt. Thornton Creek Commons now stands as an example of what can be achieved by city housing developments, combining convenient location and aesthetic appeal without sacrificing energy efficiency and cost-conscious practices.
Pruitt considers the development’s success to be a sign of the direction the housing market as a whole should take. “Market demand for artful, high design and carefully crafted multi-generational homes with single-level lifestyle features remains strong,” she says. “Providing great design and high performance is fundamental and is rewarded in the marketplace. Buyers understand and desire a higher quality new home.”
Each home’s garage includes an energy-efficient opener, which when combined with an insulated garage door creates a thermal barrier that reduces a homeowner’s utility bill. Credit: Clarity Northwest Photography
The inside of the home stays warm, cool, dry and clean when needed, thanks to an exceptional envelope that includes a non-vented roof system; taped and sealed seams and joints on sheathing; liquid membrane weather barrier, and barrier sealant. Credit: Clarity Northwest Photography
Windows are temperature-controlling, ENERGY STAR rated, dual pane, and argon gas filled, while all paint is zero VOC. Credit: Clarity Northwest Photography
Key Components
Appliances: Bosch dishwasher, washer, and heat pump dryer; Bertazoni induction range; Beka refrigerator; Rheem heat pump water heater; Frigidaire beverage center Building envelope: Stick built, no trusses, 2-by-12 rafters; non-vented roof system; taped and sealed seams and joints on sheathing; Air Guard liquid membrane weather barrier; Aero Barrier sealant; rain screen under siding; Hardie siding Cabinets, shelves, millwork: Belmont cabinets; custom millwork constructed on site by L&K Millwork Caulks and sealants: Acoustic sealant above and below sill gasket; Contega HF air sealing adhesive between joist and subfloor; Fentrim 430 tape to make air seal sheathing to stem wall; taped seams between subfloor sheets using G tap 3040BK6 to seal possible airgaps Countertops: 3-centimeter Italian white quartz Decks: Timbertek composite decking installed over pressure-treated framing Doors and hardware: Exterior doors: Therma Tru 6-feet, 8-inches fiberglass glazed door, 0.5-inch glass; Interior doors: Trimlite single panel OBOLO solid wood core interior doors Electrical: Level 2 EV charger, net zero possible; South Lake Electric, LLC Exterior finishes: James Hardie siding; Sherwin Williams paint Flooring: 7 inch, 0.75 inch T&G fir, from Sustainable Lumber, Missoula Montana; solid wood, tongue and groove, wide plank, Douglas fir, wire brushed; porcelain and ceramic tile, Marazzi, Monarch M1L7, matte, 8-by-8 tile from Dal Tile, heated first floor bathroom, shower, and hallway floors Garage door: Liftmaster, National Garage Door HVAC/ducts: Mitsubishi heat pumps (mini splits) with external compressors; Mitsubishi PEAD wall-mounted interior units Insulation: Exterior walls: Mineral wood insulation in south, west and east stud cavities; Brown in Blanket System (BIBS) in north wall cavities. Floors and ceilings: mineral wool sound barrier. Upper-level interior: Foam, fiberglass batts. Lower-level interior: foam Landscaping: Professional landscaping designed by City Gardens; Ornamental Iron security fence Lighting: Exterior lighting automatically controlled by photocell sensor; LED lighting throughout Paints and stains: Sherwin Williams no-VOC paints Plumbing/plumbing fixtures: Water Sense-certified faucets and shower heads; Toto toilets 1.28 gallons per flush; water submeters measure actual amount of water used by each individual unit Renewable energy systems (solar, wind, etc.): Pre-wired solar Roof: Non-vented roof system by Legacy Roofing Northwest, spray foam and blown-in blanket insulation to full 12-inch depth; GAF Timberline HDZ shingles; TAK Defender underlayment; TAK Grip Seal Ice & Water Shield; starter materials IAW manufacturer’s recommendation; complete flashing; high-profile ridge cap; Nu-Ray Metals Series 1000 Standing Seam Metal, D2 Dynar 500 paint finish Telecommunications: Prewired for cable (TV, phone, and internet) Ventilation: Panasonic Energy Recovery Ventilator (ERV), continuous operation Water heating: Rheem heat pump water heater Windows, skylights, patio doors: Milgard ENERGY STAR, dual pane, dissimilar pane thickness, argon gas filled Other: Noise deadening: Acoustic drywall; 0.625-inch gypsum with a layer of viso-elastic polymer sandwiched between layers: Noise deadening: Acoustic drywall; 0.625-inch gypsum with a layer of viso-elastic polymer sandwiched between layers
Alan Naditz is managing editor of Green Builder Magazine. He has covered numerous industries in his extensive career, including residential and commercial construction, small and corporate business, real estate and sustainability.
Urban Eco-Friendliness
The Cottage Company proves the feasibility of sustainable city living with a nine-unit community.
Thornton Creek Commons, a two-and-a-half-acre development in Seattle, is providing an impressive counterexample, with nine units that are environmentally friendly, conveniently located, cost-efficient and aesthetically pleasing.
Located just north of the University of Washington, Thornton Creek Commons was initially the home of the 1959-era St. George Episcopal Church, which closed in 2016 when declining membership prompted its congregation to merge with that of another church nearby.
The church structure, while initially something the development team at The Cottage Company expected to have to remove completely, proved to be a blessing in disguise (no pun intended).
From the Judges: “Beautiful integration with the local neighborhood.”
“Initially, we believed that we would demolish the 8,000-square-foot church structure,” developer Linda Pruitt recalls. “Mitigation prior to demo exposed the extensive old growth, clear wood paneling, subfloors, framing materials, hand-split old growth cedar siding, and large beams—all that could be used in the construction of the new Thornton Creek Commons community.”
With the help of the Sledge Seattle deconstruction firm, The Cottage Company salvaged 90 percent of the original church structure. The recovered cedar siding became siding for each unit’s detached garages; 4,000 square feet of 3.5-inch, double T&G car decking was milled into solid wood flooring, installed and finished in four of the nine units; and pieces of deconstructed lumber were used throughout the homes to provide aesthetic details and supportive improvements.
Environmental Efficiency
As for the homes themselves, Thornton Creek Commons is a hallmark of sustainable practices and energy efficiency. Each unit is highly insulated, thanks to a combination of mineral wood and wool, blown-in cellulose, foam, fiberglass, and the Brown in Blanket System (BIBS) on every north wall, which provides a greater depth of insulating material, a higher R value, and a complete absence of air gaps between pieces of fiberglass.
The homes’ James Hardie siding is fortified with an Aero Barrier sealant and a rain screen underneath, ensuring that the moisture for which the Puget Sound is known never seeps into the homes. A continuously operating Panasonic Energy Recovery Ventilator (ERV) and Rheem heat pump water heater ensure clean and efficient air and water in the home, while Mitsubishi mini-split heat pumps with external compressors and PEAD interior units keep each unit comfortable and quiet.
The homes’ location was an environmentally conscious decision. Just three blocks from the Lake City urban village core, Thornton Creek Commons is less than a 10-minute walk away from grocery stores, banks, the post office, restaurants, and the local library. The nearby Link light rail station allows residents to get nearly anywhere they need in the city, all without the use of a car.
Thornton Creek Commons also includes recreational space to take advantage of the area’s natural beauty and proximity to the eponymous Thornton Creek, including an off-leash dog park, fire pit, and gardens, as well as dedicated access to northeastern Seattle’s largest flowing watershed.
Click to view a larger image
Community Outreach
Like any project, construction of Thornton Creek Commons was not without difficulties. While the Diocese of Olympia, the owners of the original property, was regularly supportive of The Cottage Company’s efforts (and had approached the company with the project to begin with), the city of Seattle itself was less than helpful.
The property was surrounded by existing, already-built single-family homes, Pruitt notes. But it was completely undeserved by sufficient public infrastructure. This necessitated the installation of new public water supply connections and public system improvements, new public sewer connections, new public stormwater connections and onsite stormwater detention and mitigation improvements, and new electric transformer installation and connections.
All of this, plus the required public improvements, had to be paid by the private development—and only the private development—at large expense. “This is one of the key contributors to the high cost of new home construction, making new single-family homes unaffordable to many,” Pruitt says.
Nonetheless, construction continued, and the results were worth it, according to Pruitt. Thornton Creek Commons now stands as an example of what can be achieved by city housing developments, combining convenient location and aesthetic appeal without sacrificing energy efficiency and cost-conscious practices.
Pruitt considers the development’s success to be a sign of the direction the housing market as a whole should take. “Market demand for artful, high design and carefully crafted multi-generational homes with single-level lifestyle features remains strong,” she says. “Providing great design and high performance is fundamental and is rewarded in the marketplace. Buyers understand and desire a higher quality new home.”
Each home’s garage includes an energy-efficient opener, which when combined with an insulated garage door creates a thermal barrier that reduces a homeowner’s utility bill. Credit: Clarity Northwest Photography
The inside of the home stays warm, cool, dry and clean when needed, thanks to an exceptional envelope that includes a non-vented roof system; taped and sealed seams and joints on sheathing; liquid membrane weather barrier, and barrier sealant. Credit: Clarity Northwest Photography
Windows are temperature-controlling, ENERGY STAR rated, dual pane, and argon gas filled, while all paint is zero VOC. Credit: Clarity Northwest Photography
Key Components
Appliances: Bosch dishwasher, washer, and heat pump dryer; Bertazoni induction range; Beka refrigerator; Rheem heat pump water heater; Frigidaire beverage center
Building envelope: Stick built, no trusses, 2-by-12 rafters; non-vented roof system; taped and sealed seams and joints on sheathing; Air Guard liquid membrane weather barrier; Aero Barrier sealant; rain screen under siding; Hardie siding
Cabinets, shelves, millwork: Belmont cabinets; custom millwork constructed on site by L&K Millwork
Caulks and sealants: Acoustic sealant above and below sill gasket; Contega HF air sealing adhesive between joist and subfloor; Fentrim 430 tape to make air seal sheathing to stem wall; taped seams between subfloor sheets using G tap 3040BK6 to seal possible airgaps
Countertops: 3-centimeter Italian white quartz
Decks: Timbertek composite decking installed over pressure-treated framing
Doors and hardware: Exterior doors: Therma Tru 6-feet, 8-inches fiberglass glazed door, 0.5-inch glass; Interior doors: Trimlite single panel OBOLO solid wood core interior doors
Electrical: Level 2 EV charger, net zero possible; South Lake Electric, LLC
Exterior finishes: James Hardie siding; Sherwin Williams paint
Flooring: 7 inch, 0.75 inch T&G fir, from Sustainable Lumber, Missoula Montana; solid wood, tongue and groove, wide plank, Douglas fir, wire brushed; porcelain and ceramic tile, Marazzi, Monarch M1L7, matte, 8-by-8 tile from Dal Tile, heated first floor bathroom, shower, and hallway floors
Garage door: Liftmaster, National Garage Door
HVAC/ducts: Mitsubishi heat pumps (mini splits) with external compressors; Mitsubishi PEAD wall-mounted interior units
Insulation: Exterior walls: Mineral wood insulation in south, west and east stud cavities; Brown in Blanket System (BIBS) in north wall cavities. Floors and ceilings: mineral wool sound barrier. Upper-level interior: Foam, fiberglass batts. Lower-level interior: foam
Landscaping: Professional landscaping designed by City Gardens; Ornamental Iron security fence
Lighting: Exterior lighting automatically controlled by photocell sensor; LED lighting throughout
Paints and stains: Sherwin Williams no-VOC paints
Plumbing/plumbing fixtures: Water Sense-certified faucets and shower heads; Toto toilets 1.28 gallons per flush; water submeters measure actual amount of water used by each individual unit
Renewable energy systems (solar, wind, etc.): Pre-wired solar
Roof: Non-vented roof system by Legacy Roofing Northwest, spray foam and blown-in blanket insulation to full 12-inch depth; GAF Timberline HDZ shingles; TAK Defender underlayment; TAK Grip Seal Ice & Water Shield; starter materials IAW manufacturer’s recommendation; complete flashing; high-profile ridge cap; Nu-Ray Metals Series 1000 Standing Seam Metal, D2 Dynar 500 paint finish
Telecommunications: Prewired for cable (TV, phone, and internet)
Ventilation: Panasonic Energy Recovery Ventilator (ERV), continuous operation
Water heating: Rheem heat pump water heater
Windows, skylights, patio doors: Milgard ENERGY STAR, dual pane, dissimilar pane thickness, argon gas filled
Other: Noise deadening: Acoustic drywall; 0.625-inch gypsum with a layer of viso-elastic polymer sandwiched between layers: Noise deadening: Acoustic drywall; 0.625-inch gypsum with a layer of viso-elastic polymer sandwiched between layers
By Alan Naditz
Alan Naditz is managing editor of Green Builder Magazine. He has covered numerous industries in his extensive career, including residential and commercial construction, small and corporate business, real estate and sustainability.Also Read