Is net zero possible in my cold/hot/cloudy location?
Yes. We build net-zero houses in the Pacifc Northwest, which is cloudy and yields 3.5 hours of sunshine per day on average. With this level of cloudiness, we spec between 3.1 watts of solar per square foot (for a 2,500-square-foot house) to 4.8 watts per square foot (for a 1,000-square-foot house) to achieve net zero.
Does a net-zero house have batteries?
Not necessarily. A net-zero house does not need batteries because the house is tied to the electricity grid. Because net-zero houses are often all electric, a battery is a good idea if your area has power outages. You can also keep a generator for these eventualities.
Does a net-zero home cost more to build?
Yes. A net-zero house has to include solar panels to generate energy.
How much will I save on my energy bills?
You will save all your heating and cooling costs. You will also save all your electricity costs. The only charge that might remain on your bill is a monthly service fee that your utility may charge.
What is net metering, and is it available in my area?
Net metering is an essential part of a net zero-house. Net metering is the name for the process by which the electricity utility accepts your electricity production from your rooftop solar panels in the summer and distributes that electricity onto the grid, effectively giving you credit with that utility. Net metering allows you to draw on that credit in the winter when your rooftop solar panels don’t generate enough energy to power your house. To be net zero, the summertime electrical overproduction is equal to the wintertime electrical need. Call your electricity provider and ask them if they will “net meter” your rooftop solar panel installation.
Why isn’t every home net zero?
A net-zero house is very, very well insulated to ensure that only a small amount of energy is needed to heat or cool it. Not many houses are well enough insulated to be cost effectively net zero, although you can always add more solar panels. Importantly, a net-zero house must have the means to produce energy, which is often solar panels. There must be enough roof space to locate solar panels, and the panels need to be installed.
What materials do you use in your net zero houses?
The walls and roof are SIPs (structural insulated panels), stem walls are ICFs (insulated concrete forms), and we specify a concrete slab-on-grade atop 4” of foam. We specify triple-pane windows and insulated exterior doors. We always specify a heat pump as the heat source. We also always specify an HRV (heat recovery ventilator) to meet ventilation code and ensure great indoor air quality.
Is the plumbing and electrical in the SIP walls & roof?
There is no plumbing in the SIP walls and roof. It’s all designed to be located in the internal walls. Electrical wires can be pulled though the factory pre-bored tunnels in the SIPs.
What can I do if my contractor doesn’t use SIPs & ICFs?
We can help you to find another contractor. Alternatively, we can meet with your contractor and explain the SIPs and ICF processes and further explain the benefts to that contractor. We can draw upon considerable experience with our sister company TC Legend Homes, which made the shift to SIPs and ICF years ago for both financial and energy efficiency reasons.
Do you design basements?
Basements are expensive and can leak, so we choose not to design basements. We can design walk-out basements but prefer to design stilt-houses because they are cheaper to build and eliminate the leak hazards.
Does my roof have to face south for my home to be net zero?
No, it’s possible to point the roof away from south and still be net zero with additional solar panels.
How accurate is your Cost-to-Build Calculator?
Our cost-to-build calculator is generally +/- 10 percent accurate. Consult local contractors for a more accurate estimate for your area.
Where does the data for your cost-to-build estimates come from?
The data comes from our TC Legend Homes construction business. That business builds five houses a year on average in northwest Washington state. TC Legend is a lean company with streamlined processes. Your local contractor may be less efficient.