Custom home builder Steve Weise has teamed up with REALTOR® Brenda Nunes to offer homebuyers a truly unique option in the small central Washington community of Selah: A zero energy development where all 60 homes feature 5-star Built Green and Indoor airPLUS certifications. The homes at SelahVista give homeowners peace of mind of owning a healthy home where they pay nothing for energy. 

Steve became keenly focused on healthy homes after one of his custom home clients hired him to build a home without the toxic chemicals common in conventional construction. In the process, he realized that he himself had been suffering from his own occupational exposure to the volatile organic compounds (VOCs) emitted by the adhesives ubiquitous in standard home construction. 

“I had severe sinus headaches from the adhesives,” he said. “It set me on the path away from toxic homes.” The path led him to Washington’s Built Green program that certifies homes that are healthier and more energy efficient than conventional construction. “For me it all flows from the pursuit of a healthy home. We use building materials with low toxicity, such as low-VOC paints and adhesives. We build an extremely tight home that keeps out polluted air while providing a continuous flow of filtered outside air.” 

 

The Power of Certification

At the 5-star level, Built Green incorporates a package of third-party certifications, including USDOE’s Zero Energy Ready Home, USEPA’s Indoor AirPlus, and ENERGY STAR. “These programs set consistent standards and guide builders toward a package of proven features that work together. It’s a good way to cover all the bases,” said Steve. 

Third-party certifications provide buyers with reassurance that  the home contains all the essential elements of high-performance home that protect the health of occupants, while eliminating monthly energy payments and slasings the home’s climate impact. Partnering with Washington’s Built Green program not only provides certifications, but ensures that SelahVista homes include the latest materials and techniques for energy and water conservation. And, “homebuyers don’t have to take our word for it,” added Brenda. “Certification means that we have independent verifiers that inspect every home.” Homeowners can trust that homes with these certifications are everything they claim to be: energy efficient, healthy, comfortable, and durable. 

 

Air Tightness and Fresh Air Systems

“The key is to build air tight,” said Steve. “On average, we reach a tested air leakage rate of 0.5 air changes per hour at 50 pascals (ACH50).” This is not only the most cost effective way to reduce energy use for space heating and cooling, but it’s also the primary path to ensuring a healthy home. It allows the home to be pressurized to prevent outdoor air from leaking in.

With an extremely tight building envelope, air flow can be carefully monitored and controlled. Moist, stale indoor air is pulled from bathrooms and passes through a heat recovery ventilator (HRV) to capture about 80% of its energy before it is expelled. The captured heat transfers to incoming outside air, which is continuously drawn into the house. Before it reaches the HRV, outside air flows through both a carbon filter and a HEPA filter. Once scrubbed, the air gets distributed through a Mitsubishi horizontally ducted mini-split heat pump. It’s an integrated system that ensures that comfort and clean air reaches every corner of the house. 

While outdoor air quality is often an issue in urban areas, it’s increasingly important in the American West because wildfires have been filling the air with unhealthy smoke for weeks at a time. An air-tight home with filtered, fresh air offers a safe refuge that conventional homes don’t provide. 

“Your house is not as safe as you think,” said Steve. “Brenda moved into one of our first homes and installed an indoor air quality monitor. Before she moved in, I was checking the house remotely while on a trip to Europe. During a smoke event, I watched as PM 2.5 levels increased. My logic was to increase the flow of fresh air through the HRV with it’s MERV 15 filter, which is effectively 86% efficient at removing particles. At the time we thought it would be adequate.  Immediately, the PM 2.5 count began to soar. So I shut the system down and decided that the only way to control air quality absolutely was to add on a MERV 21 filter.” 

 

Envelope Approach

The walls of SelahVista homes are heavily insulated to R-38. “I like the double-plate wall,” said Steve. “It’s the easiest for framers to get their heads around.” Exterior sheathing is sealed with high-quality tape along all seams to limit air leakage, and then the weather barrier is carefully sealed over that. 

Spray foam insulation applied to the underside of the roof sheathing brings the entire attic inside the conditioned envelope. It’s the perfect place for the Mitsubishi horizontally-ducted mini-split heat pump and the HRV that is connected to it. 

 

Selling Benefits

Brenda leads the sales effort at SelahVista. She said that buyers need to ask good questions when comparing homes. “What is the total monthly cost to own a home? How does a zero energy home reduce the cost? What will it cost for replacement and maintenance?” Code-minimum homes may have a lower purchase price, but they will cost more to operate and have higher costs for utilities and maintenance. Buying a home that is energy efficient, durable, and healthy pays dividends to homeowners that last for decades. 

 

Appraised Value 

While it’s clear that zero energy homes cost less to own and come with considerable buying power, there is sometimes an obstacle to financing the small additional upfront cost of these homes. 

“Appraisal is definitely the toughest nut,” she said. Appraisers want comparable sales figures and these may not be available within the desired timeframe or in a similar neighborhood. It is important to ask appraisers to use the Appraisal Institute’s Green and Energy Efficient Addendum. It’s a good way to document the value of the additional energy-saving features —

 using the cost-based appraisal method. It’s best to find an appraiser who is trained and certified to complete the addendum. 

In addition, the independent certifications are, according to Brenda, one of the best ways to convince appraisers of the proper market value of highly energy-efficient homes. Clearly identified features, performance testing, and independent inspections give appraisers evidence of true value. 

SelahVista has an advantage when it comes to appraising value, because it creates its own comparables. “Appraisals on the first few sales were cash only or had large down payments so they didn’t require the same high appraised value,” she said. After that, these early homes provide comps for those built later in the neighborhood. Now that SelahVista has sold seven homes, they can be used as comparables, paving the way to achieve proper appraised value for those that follow. 

 

The Future of Home Construction

Steve’s own zero energy home is a full-scribe log home, built decades ago. It’s solidly built with a roof of structural insulated panels (SIPs). The home is all-electric and has enough solar panels to generate all the power for the home and his electric car. He now sees the construction industry moving steadily, if slowly, toward zero energy. 

“Codes are the driving force, he said.” The new statewide building code in Washington will drive more builders to build very tight homes that require heat recovery ventilation. Heat pump water heaters will be much more common. Homebuyers will benefit and it’s a great time for builders to get on board. 

Brenda teaches National Association of Realtors Green Designation classes. She and Steve both see a strong need for better education of consumers, real estate brokers, and building trades. Everyone needs to better understand the total cost of home ownership, the health issues of homes, as well as the many tangible values of zero energy homes. 

A field trip to SelahVista would be a good place to start.