View Cart 0 Item

TC Legend 5-Star Bellevue Net Positive House

Located on a portion of a subdivided family property, this 2,614 square-foot Bellevue home is a beautifully built house that helps to foster multigenerational ties and community. With Built Green 5-Star and Net Zero Energy certifications and an EPA Indoor airPLUS certification, this award-winning TC Legend home is an example of the influence and success of the Built Green program.

Vital Stats



Location: Bellevue
Star Level: 5-Star, Net Zero Energy Label
Checklist: Single-Family/Townhome New Construction
Verifier: Ecoe Company
Site and Water 109
Energy Efficiency 239
Health and Indoor Air Quality 126
Material Efficiency 109
  Total Score 629

With a specific focus on indoor air quality, this home employs a new ventilation and air filtration system, helping to make it a safe and comfortable environment for its occupants. The state-of-the-art fresh air system includes a Zehnder 350 HRV, Zehnder ComfoPost inline heating/cooling coil, and HEPA air filtration system. This system allows for fresh, filtered air to enter the home throughout the day and to be increased when needed, such as when the kitchen hood fan is drawing smoke out of the kitchen during cooking. This fresh air system maintains high indoor air quality by reducing particulates in the air, even when the outdoor air quality is particularly poor, such as during a summer forest fire.

TC Legend 5-Star Bellevue Net Positive House exterior

Built with passive and active solar needs in mind, this two-story house faces south. Triple-paned Vinvltek windows on the south side provide passive heating and natural light within the home. White interior paint also helps provide significant daylighting and reduces energy demand from the home’s LED lighting.

The home also employs a 12.87kW photovoltaic system, producing enough power to make the home net positive and power an electric vehicle. With a shell system constructed from 6.5” SIPs walls, 10.25” SIPs roof, 4” foam under the slab-on-grade, ICF form slab-edge stemwalls, and U 0.18 average triple pane windows, this house has a tight envelope, helping to reduce energy consumption.

TC Legend 5-Star Bellevue Net Positive House balcony view
TC Legend 5-Star Bellevue Net Positive House wood screen
TC Legend 5-Star Bellevue Net Positive House kitchen

The three-bedroom, two bath house is meant to allow the occupants to age in place. The first floor has a kitchen, main living space, a bedroom and bathroom, and ADA-compliant doorways.

Overall, this home is a comfortable, clean, net positive building, allowing the homeowners to be happy, healthy, and confident in the knowledge that their home is serving their needs, meets a high standard of excellence, and is protecting the environment in the process.

TC Legend 5-Star Bellevue Net Positive House room with vaulted ceiling
TC Legend 5-Star Bellevue Net Positive House loft space

Built Green Highlights

Site and Water

  • Long-term erosion reduction strategies in place
  • Over 70% of building site left undisturbed with preservation of exisiting trees, native vegetation, and grass landscaping
  • Stormwater infiltration system catches all stormwater from the site and the uphill grandparents’ house, mitigating flow
  • WaterSense certified low-flow fixtures and toilets
  • Rainwater collection-ready

Energy Efficiency

  • Net-positive home with a HERS score of -22; extra power serves an electric vehicle
  • 12.87 kW roof PV array
  • Substantial envelope insulation: R-30 walls, R-49 roof, R-20 under slab, R-24 slab-edge, average U-0.18 windows
  • Triple-paned Vinyltek windows with u-values from 0.15-0.22
  • Passive heating design strategies
  • Chiltrix air-to-water heat pump for heating and domestic hot water with COP of 3.92
  • AeroBarrier air sealing and blower door results of 0.47 ACH50
  • 100% LED lighting
  • All Energy Star certified appliances
  • Energy Star certified
  • DOE Zero-Energy Ready certified
TC Legend 5-Star Bellevue Net Positive House bathroom
TC Legend 5-Star Bellevue Net Positive House showerhead and tile

Health and Indoor Air Quality

  • Indoor AirPLUS certified
  • Solid wood cabinets with low-VOC finish
  • All low-VOC paints, adhesives, and sealants
  • No gas-burning appliances in house
  • HEPA air filtration system
  • Zehnder HRV with ComfoPost

Materials Efficiency

  • Graphite SIPs for exterior walls and ceilings
  • ICF foundation walls
  • 85%+ of waste recycled
  • Locally produced lumber, SIPs, concrete, cabinets, doors, and siding
  • Exterior cedar posts constructed from telephone pole MFG waste
  • Leftover materials moved to next job
  • Solid wood, domestically grown interior doors and trim
  • Locally produced Vinlytek windows
TC Legend 5-Star Bellevue Net Positive House room with vaulted ceiling
TC Legend 5-Star Bellevue Net Positive House utility room

Photo credit: Zigzag Mountain Art

You May Also Like

Card image cap Built Green™


Change Makers Inspire the Built Green Conference

Card image cap Built Green™


Kickstarting Green Building Everywhere

Card image cap Built Green™


Haberzetle Homes: Playful All-Electric Townhomes