In keeping with a theme… We were inspired to add a regional perspective to the Pretty Good House idea, written up in the Green Building Advisor by Michael Maines and continued by Allison Bailes at Energy Vanguard, here is Part 2 of his effort. I asked our exceptional staff of HERS Raters and Auditors for their thoughts. Here is Steve Eagleburger with his thoughts. Steve is also a PHIUS+ person and quite passionate about PassiveHaus among other things.
So what does that mean? Is current code pretty good? Is Energy Star version 3 pretty good? I would say yes they are. When you compare houses built to code today to houses built say, 20 years ago there have been major improvements. The codification of air barriers is one example. The introduction of house tightness and energy modeling is another. Energy Star version 3 is bringing in thermal bridging issues, duct leakage, quality installation and HVAC system commissioning, all of which leads to a better performing house. So where to go from there? Semantics are everything when selling a product or an idea, so I would say rather than shooting for “pretty good” let’s go for “a little bit better”. How can we get there without major cost and retraining of trades?
First thing to do in our high desert/plains climate is let the Sun in! We have an abundance of free solar energy and it’s a simple proposition to face a house within 15 degrees of South. It may take some educating of developers and planners to swing new suburbs towards the sun but it can be done. We must also control summer sun with overhangs and minimize west facing windows. Here comes the cost issue- builders must start using low u-value/high solar heat gain coefficient windows on the south side. This cost could be recouped by installing fewer windows on the north and west side.
Now that we’ve pointed our house in the right direction we need to insulate and air seal properly. Energy Star and the IECC are heading in the right direction but there are too many loopholes. Houses need to be wrapped head to toe with at least R-5 of rigid foam above grade. Period. Advanced framing does little to reduce energy use. Foundations should be R-20, R-10 under slab, 2×6 R-23(+5) walls and R-60 in the attic. Mechanical rooms need to be treated as exterior spaces and sealed tightly or all appliances need to be sealed combustion. Houses we test are already coming in at around 2 ACH50 or better, so let’s get them down to 1 ACH50.
We can build this way without major retraining or cost adjustments but will the homeowners understand how the home operates? It’s been said that there are no zero energy homes, just zero energy homeowners. As an energy auditor I’ve been in homes built 50 years ago and no one has ever been in the attic. Countless times I’ve seen window shades drawn on a bright winter day. We all know we’re supposed to change the oil in our cars on a regular basis so why shouldn’t we understand that putting a bag over the combustion air inlet to stop that cold air from coming in the basement is dangerous, or that when the Sun shines in it warms up the house, or that 2” of ratty old fiberglass in the attic just isn’t acceptable. So let’s spend some time and resources educating homeowners.