Building Net Zero Homes

If you’ve never considered how building net zero homes can serve your clients and impact your bottom line, now is the time. It’s likely to be a big part of homebuilding’s future, and many builders have already made the leap.

"The best builders are learning to build homes with zero net energy use," according to Sam Rashkin, chief architect at the US Department of Energy's (DOE’s) Building Technology Office, who led the ENERGY STAR for Homes program for more than 16 years. Rashkin and his team are behind the DOE Zero Energy Ready Home program, which offers excellent resources for both homeowners and builders.

Building to Zero

To earn the Zero Energy Ready Home label, a home must score in the low to mid-50's on the Home Energy Rating System (HERS) Index (a score of 100 is code-minimum). Add a modest solar array, and the home will put more energy into the grid than it uses on an annual basis.

One builder who has gone all-in with net zero is Tampa-area Marc Rutenberg, of Marc Rutenberg Homes. Rutenberg just opened a "no electric bill," LEED Platinum, net zero model home, and is breaking ground on a 14-home Zero Energy Village.

Homebuyers have been enthusiastic. "Most didn't know this was an option," says Rutenberg. He adds that while building to net zero adds cost, the energy savings more than compensate for the increased mortgage payment.

Other builders also rave about the benefits of this approach. Milwaukee-area Tim O'Brien Homes opened Wisconsin's first zero energy neighborhood in late 2017. According to Craig North, vice president of product innovation, the 34 lots pre-sold faster than any of the company's other neighborhoods.

Sales Success

Both Rutenberg and North help buyers understand bottom-line monthly costs, which include mortgage payments, energy bills and maintenance. That's where the HERS rating comes in: it quantifies a net zero home's lower cost of ownership. Realtors and buyers are catching on. Some multiple listing services now list HERS scores, and a 2016 study by the North Carolina Building Performance Association found a strong link between a lower score and a higher sale price.

The Right Building Products

Great insulation and air sealing are crucial to a low HERS score, but net zero builders go further. "We scrutinize everything from the HVAC system to the motor on the garage door opener," says Rutenberg. He insists on ENERGY STAR appliances, LED lighting and top-quality windows. "We spec a JELD-WEN window with triple Low-E glass, regardless of whether it has a vinyl or a clad wood frame."

Rutenberg is shooting for a negative HERS score — a house that generates more power than it consumes. That's why he opts for triple glazing. However, Jason Kantola, JELD-WEN's Coordinating Certification Manager, says that a double-paned ENERGY STAR rated window will often meet a builders' net zero needs. "We have quoting tools and performance charts that make it easy to pick the right window," he says.

Training for Builders

Net zero homes are more airtight than required by most energy codes. To guarantee healthy indoor air, they need proper ventilation. To avoid moisture issues, they need appropriate construction details. Getting everything right requires a firm grasp of modern building science.

The DOE offers online training, but Rashkin recommends live seminars, such as those put on by the Energy and Environmental Building Alliance (EEBA), which cover basic building science, mechanical systems and the HERS Index. North says EEBA training has been invaluable in his company's path to zero. "The lessons learned have been instrumental in differentiating ourselves from the competition."

For windows and doors suitable for LEED platinum, net zero home building, visit JELD-WEN’s professional portal.

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