Caption: Average monthly energy bills are $14 at the Villas at Rocketts Landing, DOE's 2017, Housing Innovation Award Winner, thanks to a combination of solar power, tight construction, air sealing and innovation HVAC system placement and insulation.
Building scientists are a data-driven skeptical bunch. When asked what we homeowners can do to reduce bills and increase comfort, one responded, “there are no silver bullets and no unicorns here.” Fair enough, but after talking to some very independent-minded home performance problem solvers and insulation and HVAC specialists, there was a clear consensus: start by air sealing - find air leaks and fix them - and only hire those who see your home as a system.
“In the past HVAC techs would show up at the door, knock and go straight to the equipment. That should never be the first stop,” says Stephen Rardon, an HVAC contractor, owner of Rardon Home Performance. “The HVAC system heats or cools within an envelope, Rardon continued. “When I talk to my heros in the industry, they almost always say that when you’re looking to boost comfort, first focus on control. If you have control of your environment you’ll be able to keep it comfortable,” he added.
“Building science is really about focusing on the big picture,” explains Allison Bailes PhD in physics, co-founder of Energy Vanguard and a pro’s pro in building science. As he explained in a widely shared 2017 blog post, “... we need to know which direction heat, air, and moisture are likely to flow. In analyzing failures, we can rely on that direction of flow to help us understand what happened.”
Bailes argues for an energy audit, the use of a equipment like blower door test, “to see how leaky a house is and pinpoint the problems.” Similarly, Nate Adams, founder of Energy Smart Home Performance and author of The Home Comfort Book, argues that contractors and HVAC specialists can’t remedy what they can’t measure and encourages homeowners to hire a contractor to do an energy audit and blower door test.
Moreover, testing at home is not an end in itself but a mechanism to improve the lived experience. “The reason to do a project is to make your home more comfortable and healthy. A common question we ask in our world is ‘What's the payback on granite countertops?’ Do the blower door test and commit to a project to make your home better,” Energy Smart Home Performance’s Adams added.
And what do building scientists tend to find, what do those tests generally find, and how do the pros look to get control of the envelope?
Start with Air Sealing
“Nine times out of ten, the items on the top of the list are related to air sealing. As we say - seal tight, ventilate right,” Matt Patmon, BPI-certified, owner of Triangle Radiant Barrier in North Carolina agreed. “Air sealing doesn’t cost a lot of money and you get an outstanding result. It is simply always most affordable.”
Adams too agreed, “Here are my top five: air seal, air seal, air seal, insulate, and install the right HVAC system.”
And where to start fixing air leaks?
“The attic and crawl spaces. Most attics have pulldown stairs. The attic hatch is always an easy go-to air sealing opportunity. I’m extremely surprised when I see an attic hatch that isn’t leaking, ” Rardon of Rardon Home Performance shared.
Look Up in the Attic
“Look up in the attic, that’s where you have the most extreme temperatures - if it’s a 90 degree day in the summer, up in the attic it’ll be 120-130 degrees,” says Patmon of Triangle Radiant Barrier, ‘In the attic it is all about air sealing - insulation doesn’t block air and getting rid of air leaks around the penetrations between the drywall and attic, the cut-ins for the lighting and most importantly, the attic hatch. The attic hatch is inevitably the biggest source of air leakage.”
“The traditional solution for attic hatch air sealing had been foam board and weatherstripping,” explains Tom Sprouse, co-founder of Creative Conservation, a high performance insulation company located in Richmond VA. He prefers a new, locally designed and manufactured attic hatch seal, Attic Zipper, which is more pliable, resilient and easier to install in existing homes or new builds than traditional solutions.
While the building scientists caution against looking for silver bullet solutions, those who find new ways to solve chronic high-frequency problems like attic air sealing are compelled to share what they learned. Jay Epstein, the 2017 recipient of the Department of Energy’s Housing Innovation Award for Zero Energy Ready Home (EZEH), elected to use Attic Zipper attic hatch products at Rocketts Landing, a first-of-its-kind affordable net zero solar homes in Richmond, Virginia. “We use what's called an attic zipper, which is a sensational piece that actually works well, where you can actually Velcro R-50, which is what we have in our attics above it, and it's just a great, simple piece of technology,” he explained in his 2017 DOE Housing Innovation Award webinar.
Focus on the Crawl Spaces Openings (Especially Drop Down Stairs)
At Rocketts Landing, Attic Zipper achieved a 1.23 ACH and 486 CFM @ 50P. Or to put it in more general terms, “This product really works,” Epstein said. “Stopping air leakage in the attic and conditioned crawl space is an important factor in designing a net zero home. The Attic Zipper for attic and conditioned crawl access stops the normal air leakage in conditioned crawl access doors and attic access opening. This product really works.”
And increasingly, insulation, HVAC contractors and home performance experts say homeowners are being more proactive around taking steps.
Caption: Attic Hatch Covers like this 'Attic Zipper' being installed in Richmond Va, combat air leaks and add much needed insulation to attic stair openings. Experts suggest focusing on air sealing when homeowners look to boost comfort, reduce HVAC system fatigue and drive down heating bills.