Photovoltaics | TC Legend Homes

Forest Hill House

by Senna | Sep 29, 2021

The Forest Hill house was commissioned by a night-shift worker with a love of house plants & the land upon which he was raised. The lot, bequeathed by grandma, faces due south with a big sky view, interrupted only by a distant fir; ideal for passive solar harvest, active photovoltaic (PV) harvest, and vegetable harvest!

Built over the winter of 2020/ 2021, Jeff tells me the build was all straightforward, except grinding down the interior slab-on-grade after the stick-frame walls were built. The grinder is a frustratingly twitchy machine, time consuming, and no one’s favorite job. The result however is a beautiful concrete floor with the aggregate cut-through, showing patina from the bull-float & the cream in the concrete. This floor will endure through many years of very hard wear.

Equally durable materials are used to clad the SIP roof & walls; NuDura metal roofing & Hardie fiber-cement lap siding combine to protect the insulating SIPs foam panels. The siding was hung in-house by TC and the fellas did a fabulous job of precisely stacking the board-joints, setting up a very pleasing pattern in the siding.

To clad the small 6” ICF (Insulated concrete form) upstand, TC uses colored 26 gauge metal to protect the insulating foam from impact & abrasion.

The highly insulated energy-shell enables this home to be heated with 12Btu/ hour (max) Fujitsu minisplit. This is an all-electric, net zero house, ready for the future. Including the coming storms….

Battery power is a hot topic these days, with grid managers planning for greater grid efficiency by storing off-peak grid surplus in privately owned battery systems.

TC Installed the 5Kw LG lithium-ion house battery on the exterior north wall. Integrated with the PV, the battery allows the PV produced electricity to be stored, ensuring this all-electric house works even when the power goes down.

Neos House

by Senna | Aug 26, 2021

The Neos house is a 4 bedroom family house. 2614 square feet. Completed in spring 2021.

Designed as a multi-generational home with one full bathroom & one full bedroom on the 1^st floor, if the piano-room & the rec-room were enclosed with walls we’d have a 7-bedroom home. Enough for a substantial family to live together.

Pointing south, the view looks towards the huge garden.

The garden spills into the dining area through sliding doors. The folks who commissioned this home are gardeners, with kids, who will be drawn towards the natural world as a way to thrive.

The weather briefly nips at you as you walk from the front door to the garage under the covered walkway, creating a connection with the day’s weather and the world outside the energy-shell.

The SIPs installation was subcontracted because this is a Bellevue job & the TC crew have northern families & want to be home at night if possible. Issac taught a Peruvian framing crew how to sling the SIPs and the job ran fast & smoothly using advanced SIPs details required by the Bellevue jurisdiction.

Despite one design mistake (the mechanicals are in the unheated garage), this house is an exercise in textbook design for cost & energy performance.

The client did a stellar job of following design advice & the crew lovingly built the house, sealing the envelope to 0.6 air changes per hour, Passivehaus standard. The result is an economical house that has won a Department of Energy Grand Prize, attained 5-star Build Green certification and is certified Net Zero.

The envelope & mechanical systems are all drawn from the 2020 TC system: 6.5” walls, 10.25” SIP roof, 4” R20 foam under the slab, R24 ICF’s, Chilltrix CX34 heatpump with (1) fancoil upstairs, Zehnder 350 HRV with comfopost heat/ cool delivery. Vinyltek triple pane windows & Thermatru front door.

All the stormwater from the roof is infiltrated back into the onsite soils via a huge infiltration trench. Additionally, the excavation soils all remained onsite to reduce soils trucking. The clients took responsibility for seeding the exposed construction soils, choosing to plant a complex cover crop in place of the usual grass. The cover crop can be tilled back into the soils to impart nitrogen & other nutrients when a new planting regime is decided upon.

The house in a garden is a traditional family way of life and TC is proud to have built a modern, dense & flexible version of this ideal, updated to make all its own power to address the demands of the climate-change world.

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Saint Claire Powerhouse

by Senna | May 3, 2020

This 1,900 square-foot 3 bedroom clerestory home, with an additional 672-square-foot attached garage located outside the SIPs shell, was built in 2016 in western Washington.

Because the master bedroom and bathroom were required to be located on the first floor, the clerestory design allowed us to locate two additional bedrooms and a bath on a minimal second floor, while leaving the glorious and spacious SIPs vaulted ceiling within the main living & kitchen spaces.

The play of light from the second-floor clerestory windows penetrates deeply into the main living spaces, eliminating glare at the large south windows and providing unusually even and dynamic day-lighting within the kitchen and living room. The occupants feel connected to the sweep of the sun, clouds, and weather patterns outside.

This is a near-perfect lot for a solar-panel net-zero home, identified by the clear solar exposure to the south, with no trees or buildings between the building and the sun.

SPECS/FEATURES

Department of Energy Net-Zero certified
Chilltrix CX34 air-to-water heat pump
100% on-site storm water infiltration via 30-foot dispersion trench
10.8 kW of solar panel installed
6.5” R-29 SIPs walls
10.25” R-49 SIPs roof
4” R-20 foam under 4” concrete slab-on-grade for thermal mass
5.5” foam (total) R-23.8 insulated concrete form (ICF) perimeter stem walls
Vinyltek Boreal series triple-pane windows (U values from 0.14 to 0.16)
1:1.6 aspect ratio floor plan, with the long side facing south
Minimal east and west glazing

Worrell

by Senna | Apr 16, 2020

This 1,340 square-foot single-story, south-facing rural home was built for a professional couple in western Washington in 2018. It features an additional 576-square-foot attached garage to the north. The unheated garage, which sits outside the SIPs shell, is stick framed to reduce building and energy costs.

The home’s two offices are permitted as legal bedrooms, so it’s really a three-bedroom, two-bath net-zero rambler with a huge south-facing roof that has space for enough solar panels to power two electric cars and run the house.

Specifications

Department of Energy Net-Zero certified
Fujistu 9RL minisplit heat pump
100% on-site storm water infiltration via 40-foot dispersion trench
70 trees and 160 shrubs were planted that will grow a forest on site
10.8 kW of solar panels installed
6.5” R-29 SIPs walls
10.25” R-49 SIPs roof
4” R-20 foam under 4” concrete slab-on-grade for thermal mass
5.5” foam (total) R-23.8 insulated concrete form perimeter stem walls
Vinylek Boreal series triple-pane windows (U values of 0.14 to 0.16)
1:1.6 aspect ratio floor plan, with the long side facing south
Minimal east and west glazing

Trax

by Senna | Apr 16, 2020

This 2,540 square-foot clerestory (one-and-a-half story) family house has an integrated, differently heat-zoned 1,040-square-foot garage and woodshop sitting within the SIPs shell. It was built in 2020 in western Washington.

A rigorous passive-solar window design uses the majority south-facing glazing for wintertime heating, shaded in summer by a shallow south porch and accurate south clerestory overhang. Multi-direction daylight penetrates and reflects deep into the connected main living space and second-floor balcony via the high second-floor clerestory glazing.

Multiple cutting-edge HVAC and home-automation systems integrate to deliver low-cost air-to-water heat pump-based central heating, cooling, and fresh-air delivery, triggered via automatic carbon-dioxide and humidity sensors. Alexa-driven automated lighting and blinds are installed, a home-automation system that will expand in its capabilities as more options become available.

The clients’ requirement for a spacious first-floor master suite led us to design a smaller second floor in relation to the first. The clerestory design accommodates this layout by producing a daylight-rich one-and-a-half-story house.

Specifications

U.S. Department of Energy Net-Zero certified
Chilltrix CX34 air-to-water heat pump
Zehnder 550Q heat recovery ventilator (HRV), with in-line fan coil from Chilltrix
Development dedicated 1 acre of pastureland to a perpetual conservation easement, ensuring growth of native species
12.4 kW of solar panels installed
6.5” R-29 SIPs walls
12.25” R-59 SIPs roof
4” R-20 foam under 4” concrete slab-on-grade for excellent thermal mass
5.5” foam (total) R-23.8 insulated concrete forms (ICF) perimeter stem-walls
Vinylek Boreal series triple-pane windows (U values between 0.14 and 0.16)
1:1.6 aspect ratio floor plan, with long side facing south
Minimal east and west glazing