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INTERVIEW: Building Science Pioneer Dr. Joe Lstiburek on the Good, Bad and Ugly Side of Buildings
Photo © Building Science Corp
Inhabitat: We talked about the curtain wall or glass being a key concern of energy efficiency in buildings. What else is a major issue right now?
Joe Lstiburek: In my view, over-ventilation.
Inhabitat: Is that ASHRAE’s fault or just people are doing above and beyond?
Joe Lstiburek: Well, ASHRAE is dominated by a vested interest in politics and LEED is even worse, if you can imagine that. I mean could you imagine getting a LEED point for increasing the ventilation 30 percent above ASHRAE and ASHRAE’s is already out of control.
The answer is source control, dilution is not the solution to indoor pollution and increasing ventilation rates is a horrible problem. The right way to do it is to not have the contaminant built into the building in the first place. And despite all of the people saying that there’s a clear link between certain levels of contaminants and medical effects, the epidemiology hasn’t been done.
People claim that it’s been done, but believe it or not, we don’t have the information in houses. We don’t know what the contaminants are. They have not been measured carefully and we’re making national policy decisions on ventilation going blind, with a bunch of people just getting together and offering an opinion. And the opinion is based on which political faction has managed to stack the ASHRE committee with their dominant voting block.
That’s not the way to do this. I mean you’d think with the amount of energy that buildings consume, and the amount of energy that residential buildings consume, that maybe somebody, like the federal government, would actually fund a study. You would need $20 million or $30 million and to go around and measure a whole slew of things in houses. That’s not been done, but yet, changing the ventilation rate by 15 or 20 percent is going to have more than that impact cost-wise on energy within the first year.
This kind of stuff drives me crazy. They manage to piss away money on stupid s*** and they can’t seem to fund something that’s important.
And the same thing in commercial buildings. You know, people are claiming that this level of formaldehyde is dangerous and this level isn’t. What’s all of this based on? I mean most of the limits and for indoor air in buildings we’re simply taking occupational numbers and dividing by ten. Why not dividing by 12? Why not dividing by 15? In California, because California is crazy on every conceivable level, they divide by 100. So, in one state the occupational number because the indoor number by dividing by ten and California divided by 100. If people knew how arbitrary and capricious this was they’d go, “Well, you’re kidding me.”
Inhabitat: Is California basing their numbers on European models?
Joe Lstiburek: No. It wasn’t based on any models. What’s amazing is formaldehyde in houses doesn’t respond to ventilation rate changes. So if you’re ventilating at 0.1 versus 0.2 versus 0.3, the formaldehyde concentration remains constant. The reason is the more you ventilate the more it emits. You ventilate less it emits less. Don’t put it in the building, that’s a phenomenally successful way of dealing with the problem.
I’ll give you another example, which will never happen, but late at night I dream about it — have you’ve heard of the MSDS sheets?
Joe Lstiburek: They tell you absolutely nothing. What people think that the MSDS sheets tells us is what the manufacturer puts in their product. The answer is no. That would be useful if they told us everything that went into this product and the quantities, but that’s viewed as a trade secret.
What the MSDS sheet tells us is that if you put this into the product, you have to tell us that it’s in the product and this comes from a very short list of “this’es”. In other words, in order to get on that short list it takes a lot of effort. It really has to be miserable and beyond a shadow of a doubt, bad. So there’s a very short list of what you have to notify.
What that means is that people are idiots to take anything from that list, to put it in there. So they use a whole bunch of other things that nobody knows anything about or haven’t made it to the list, but they don’t have to tell you about it. I always laugh –LEED and other people want you get to the MSDS sheet – and I’m saying “Why?” What you need to do is you need to take one of the guys who makes this stuff out to dinner, get him drunk, and ask him: “What’s in there?”
Inhabitat: Another study funding opportunity for the U.S. government?
Joe Lstiburek: Well, not funding – basically, change the law. Make them tell us what’s in their products.
Inhabitat: So that regulation would make complete sense?
Joe Lstiburek: Phenomenal sense. Tell us what’s in it.
Inhabitat: Let’s get back to energy a little bit. Is thermal bridging the next cusp of people’s thinking about how building envelopes work?
Joe Lstiburek: Well, it’s no mystery to anybody who knows about buildings that it’s a big deal. I’m kind of amused that people are just figuring out well, glass is really bad and there’s too much it. Not having insulation continuously is a big deal.
What’s even more important is that air tightness is even more important. There’s no requirement for air tightness. How can you with a straight face talk about energy efficiency and not have a requirement for air tightness?
Inhabitat: How would you test for air tightness in a large building?
Joe Lstiburek: It’s easy. Every building has a mechanical system. You just simply open all of the interior doors and turn on the exhaust fan and measure the pressure difference, then close the exhaust fan and turn on the supply fan and measure the pressure difference. You got your entire building leakage.
You don’t even need to do it that way. Just simply take a compartment and measure the pressure in the compartment. You don’t have to measure the whole building, just measure pieces of the building. There are a lot of ways to do this.
I wrote about it in Understanding Air Barriers on our web site and actually did my doctoral dissertation on how some of this can be done. It’s just that it takes about a half a day to set up the test and about 15 minutes to run the test. For people that claim that this is complicated and hard, it’s just not hard.
The problem is that because it is easy to do, and if you actually do it and you create a performance requirement, people will have to meet that requirement. That means they’re going to have to change what they do and that’s what the problem is; people don’t want to change what they do.
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