A South Carolina builder is completing a net-zero model home with some high-tech elements to meet a standard that only one other U.S. house has been able to meet.
Addison Homes of Greer, S.C., builds about 15 “healthy, high-performance” homes for clients interested in indoor air quality and energy security. Company founder and president Todd Usher hopes to build 30 per year in coming years.
“Most of our clients’ motivation is energy security, protecting themselves against future rate increases. Some have a drive to be as carbon neutral as possible. Many of our clients are Baby Boomers, so they have years of fixed income ahead of them,” says Usher.
The model home is under construction in Addison’s Trailside community in Greenville. Construction should be completed by the end of March. Usher plans to sell the house for $370,000. “It’s a little higher than the median nationwide, but with the skylights and sun tunnels, along with solar, there’s a lot of features in the house that make it a great place for living but do add a little bit of cost.”
Daylighting and the Active House Standard
Usher has applied to certify this home under Europe’s Active House standard; this would be only the second home in the U.S. to have this certification. Natural light and ventilation are two components of the Active House, Usher says.
“We have certain daylighting levels that are modeled through a daylight simulation program, and we have to meet the minimum daylight standard in the home,” Usher says.
To meet those requirements, Addison has incorporated skylights, roof windows and sun tunnels to bring natural daylight into the home.
A unique technology Addison has incorporated is the Velux automated solar venting skylight, which operates off a solar panel that sits outside the skylight flashing. It also has a rain sensor that automatically closes the skylight when it begins to rain.
“We’ve installed the venting skylights fairly high on the roofline and in a vaulted ceiling in the great room. They do a great job at using the natural stack effect in the house,” Usher says. “Open a couple windows on the lower level and a couple of the skylights and you get a great breeze. That breeze helps the moisture evaporate on your skin and it helps make you feel comfortable.”
The skylight has a wireless remote control that looks like a smartphone. It can run several programs for opening and closing including an indoor air quality program to open and close the skylight at certain times of day to bring in fresh air.
Because they include solar panels, the skylights qualify for the federal solar tax credit and for South Carolina’s 25 percent solar tax credit.
“They walk through that space, and you don’t have to turn on lights. The space just feels like a good space. A lot of us have grown to take that for granted in the homes of yesteryear with eight-foot ceilings and small windows. You walk into a house that has taken this Active House approach to natural daylighting and they say, ‘Wow, I want some of those. I want the skylights in my roof; I want the daylight coming in.’”
The home’s mechanical ventilation is handled by a Lennox ERV, the Lennox Pure Air system, which features photocatalytic oxidation technology to kill bacteria, mold spores, viruses, odors and chemical vapors and filters particles down to 0.3 microns.
But with ventilating skylights, Usher says he would have liked to be able to connect the skylights with the HVAC system to use the skylights to ventilate, but he found that the operating systems of the devices can’t communicate. That was one of the questions Active House asked during the certification process.
The other problem is humidity levels in South Carolina aren’t always conducive to opening windows.
Usher said Active House is interested in experimenting with Addison on programming a ventilation system that can sense indoor and outdoor temperature and humidity and open the skylights to ventilate the house when conditions permit it.
Connecting technologies and allowing various brands and home control systems to talk with one another is necessary for manufacturers, Usher says.