Built Green: Emerald Star, Net Zero, Energy Efficiency, Indoor Air Quality, Materials Efficiency, Design Innovation, Solar Power, Storm Water Infiltration, Advanced Building Envelope, Electric Vehicle
Having moved apartments six times since they arrived in Seattle in 2007 and becoming parents of twins in 2014, the owners were eager to build their own home to meet their needs for years to come. They found a teardown in West Seattle and decided to build a house that would be a comfortable and healthy place to raise a family while having minimal environmental impact and costing them no more than buying an existing home.
They found a great partner in TC Legend Homes, a builder who shared their values and had a track record of building market-rate net zero energy homes. This project became an especially ambitious undertaking when owners and builder decided to go for Emerald Star certification, Built Green's highest certification level that sets the bar very high across all aspects of sustainable construction, including energy and water use, materials and health & indoor air quality.
The result is this West Seattle gem, a three-story, 3,160 square foot net-zero energy home located on an urban infill lot. It includes a ground floor one-bedroom mother-in-law apartment and has three additional bedrooms on the main two floors. Flexibility was key in the design to allow the house to continue to be functional as the homeowners' young family grows. With that in mind, there are "flex" spaces on each floor, right-sized bedrooms, a generously sized utility room, and ample outdoor spaces. The owners moved in in November 2017 and were excited to hear the news that their project was the second home in Seattle to ever meet the stringent requirements of the Emerald Star level! Green building highlights include:
Water • On-site rainwater capture and storage of up to 10,000 gallons, filtration system to supply entire house with drinking water • Low-flow faucets and toilets • 80%+ reduction in water use from site collection & filtration and conservation • No stormwater runoff as a result of rainwater capture and use of pervious driveway
Energy Efficiency • Built with Structural Insulated Panels (SIPs) for efficient building envelope • Compact building shape, efficient space use • Passive solar design • Triple-pane, wood-framed, low-e windows • Heat recovery ventilation (HRV) • High-efficiency heat pump for heating and hot water • 100% LED lighting • ENERGY STAR appliances, including ventless heat pump dryer and induction cooktop • 9.9 Kw Solar PV array • Set up for 2 Electric vehicle charging stations (one in garage and one outside) • Air Sealing: 0.48 ACH 50 • Home Energy Rating System (HERS) score of zero with solar PV (41 without PV) • Energy Star v. 3.1 Certified DOE Zero Energy Ready Home Certified
Health and Indoor Air Quality • Low- and no-VOC paints and finishes • Low- and no-VOC adhesives and sealants • PVC alternatives used throughout home • Fully insulated garage air-sealed from house with automatic exhaust fan • No added urea formaldehyde wood products • No combustion appliances in house • Constant filtered fresh air supply throughout the house • EPA Indoor airPLUS certified
Materials Efficiency • Over 90% of construction waste recycled •FSC certified lumber for interior framing, flooring, trim, doors, windows, cabinets, and siding • Concrete mixed with 34% slag • Greenguard certified cork flooring • 50-year warranted fiber cement siding • Standing-seam metal roofing • Salvaged interior windows • Recycled tile in kitchen and bathrooms