CONSTRUCTION KNOWLEDGE BLOG
March 5, 2012
Back in college, one of my wrestling buddies was doing lots of research on indoor air quality and energy conservation. Princeton was a leader in developing the blower door concept to test the actual infiltration (air leakiness) of houses and apartments. I hung out in the lab, doing some solar energy/ethanol research of my own and got to know Andy Persily. Andy was a PhD student, lots of fun, laid back and scary smart. I like hanging out with smart people, the contrast amuses me.
I knew that Andy did his post doc work at the National Institute of Science and Technology (NIST) and has been working there since. Recently, I heard Andy speak at an ASHRAE meeting, giving a technical talk on the importance of reducing infiltration in building design and construction, then ventilating in a controlled way. Controlled ventilation uses Energy Recovery Units to capture the heat or the cold from the air being exhausted and transfers it to the intake air. Andy used the catchy phrase “Build tight and ventilate right”.
Most of us spend way too little effort in making sure our buildings are tight. We use the same old details we’ve used for years. In reality, the tightness of our buildings has more to do with a random tradesmen’s care (on details that aren’t clearly specified) than on anyone really focused on excellent insulation and infiltration construction details.
I challenge you and me and the entire industry to pay more attention to the biggest payback item in all of sustainable construction. If you want to be truly green, get this one right.
Our customers will soon be demanding improvements (i.e. punishing poor performance) with a cheap thermal flashlight that’s just been developed. The flashlight uses a thermal sensor and a multi-color LED to paint a heat map on the wall and find areas of poor insulation or drafty infiltration. A webcam can then capture the thermal map, per the photo below.
Take the time to study and improve the sheathing, flashing and infiltration details on your projects. Let your customers know that you strive for their best interest by paying attention to things that really matter. Remember: Build it Tight and Insulate it Right.