The term ‘building science’ is used quite often now in sustainable building circles, but much of what we understand of it can be traced back to the work of Dr. Joe Lstiburek, founder of Building Science Corporation. He is anything but your typical engineer or scientist who spends time crunching numbers or hiding away in a lab. Lstiburek has spent most of his career out in the field, testing and examining what works and what doesn’t. Many of the building standards today — from building codes to ASHRE to testing methodology — have his finger prints all over them, and his tough love criticism of building design is undercut with his wry humor and, of course, an encyclopedic knowledge of building construction. Read on to learn where buildings go wrong and what we can do about it.

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Joe Lstiburek, Building Science, green building, Sustainable building, green building expert, green building expert, ASHRE, LEED, problems with LEED

Inhabitat: What does building science really mean? Did it not exist 50 years ago?

Joe Lstiburek: Well, it always existed. It’s really the technical side of architecture that architects gave up. If architects did their job there wouldn’t be any need for building science. You know, I’m flabbergasted by the architectural profession giving up control of such a profitable part of the industry, which is the interaction of the building enclosure with the climate and the people and the mechanical system.

You know, this occurred because of the change in the focus on the education of the architects, the school. They’re focused – they’re trained in art. They’re not trained in physics and material science to actually execute their designs.

Back in the day, 100 years ago, or maybe 50 years ago in Europe, architects were trained like master builders. They understood structure. They understood mechanical. They understood physics. They understood material science. They understood how everything worked together. The focus now on the architectural education is all art and what’s missing are all of those other pieces — one of those missing pieces is building science or building physics.

Inhabitat: Do they feel like it’s not their problem? Such as how a building envelope will necessarily function in the real world — that if it’s down on paper and it’s been done before, then that’s okay?

Joe Lstiburek: I can’t speak for the architectural community, although I often try to – that is I think the arrogance of the profession drives me crazy. I think they feel it’s beneath their dignity to worry about these little, minor problems, like how to keep the rain out of the building, how to keep the air in and the air out. Let somebody else worry about that. I’m here to make an uplifting building to society to basically send a message about how this building is going to make this place a better place to live, and the people that live and work in it are better people. That’s what my mission is. This other stuff somebody else will worry about.

Inhabitat: So how do you get them excited about building science again?

Joe Lstiburek: Well, I don’t. What happens is the legal profession does that for us. The most effective technology transfer in the world is a lawsuit. They never call us when things are going well. They call us, “Oh, my God! We’re getting our ass sued because this problem occurred.” 

Joe Lstiburek, Building Science, green building, Sustainable building, green building expert, green building expert, ASHRE, LEED, problems with LEED

Inhabitat: One of my favorite things you  talk about is how highrises eighty years ago were more energy efficient than just about anything built today, especially with curtain walls and glass.

Joe Lstiburek: Well, it’s real easy. It’s just glass. I mean we have glass boxes and glass and steel are inefficient. Back in the day we had glazing ratios that were 10 and 15 percent and mass walls. An R2 curtain wall can’t compare to an R8 mass wall assembly. It’s not even close.

Inhabitat: So we talk about these advanced materials, advanced glazing options we have now and, you know, they go on and on and on. They are still nothing compared to a masonry wall as far as energy efficiency?

Joe Lstiburek: They’re nothing to the old approaches, but in the last 50 years the architectural profession has managed to piss away every energy advance that the rest of us have made because of all of the glass. I mean it’s just amazing to me.

And the hypocrisy is stunning. They blame everything. We’re here to save the planet. We’re here because it’s real important for our carbon footprint. And yet they turn out one glass box after another glass box after another glass box and they’re interested in what the emission rate of the paint is, and what the embodied energy of the carpet is, and the biggest problem is their original design. That just drives me crazy. LEED is a colossal joke for that reason. They equate a bike rack with the same efficiency as the enclosure.

Inhabitat: Everybody who wants to point LEED’s weakness uses the bike rack argument.

Joe Lstiburek: Guess what? For good reason. And you know what? They’re idiots to do that and they refuse to limit glazing ratios and they don’t measure s***.

Inhabitat: And there’s no commissioning of the envelope.

Joe Lstiburek: No. It’s crazy, and you know what? We’ve been collecting the numbers and they’re pathetic. What’s great is that, okay, now they’re going to fix it, nothing like taking a really flawed and screwed up program and having to fix it.

Well, the lawsuit that Gifford started gave them a wake-up call. The fact that people are now publishing the results and they’re pretty poor has given a wake-up call. At the end of the day, LEED is going to get fixed because they have no choice. It’s just that we’ve wasted a decade.

Inhabitat: It wasn’t just that lawsuit. You really started harping on how weak the LEED energy and atmosphere credits were in 2008.

Joe Lstiburek: I couldn’t understand why a licensed engineer or a licensed architect would have an outside bunch with a checklist supplement their professional knowledge and experience. I mean how insulting is that? Because that tells me that you are so poor as a professional that you believe that the judgment of a third-party checklist is more significant than your knowledge.

And experience as an architect or engineer. Are you kidding me? I mean I would have thrown them out of my office. I would have said, “What? Get the hell out of here.”

You go and you do this checklist thing and you’re telling me that I have to superimpose this arbitrarian, capricious checklist on my skill as an architect, as an engineer. I mean that, to me, is flabbergasting.

Inhabitat: So is it the same effect of when architects gave up the idea of building science and said somebody else can worry about it. The LEED checklist gave the architects the opportunity for somebody else to worry about what green building really is?

Joe Lstiburek: The architects have caused their own problem and only the architects can solve their own problem and I have faith that the architectural profession will fix itself. Architects need to get in charge of the process again, totally in charge of the process, and for that they need the education and the experience to do that.

There should be no reason that we have all of these outside consultants that are sucking bits of the architectural key out of the process. The architects should grab that for themselves and deliver the whole building the right way, to be the boss of the job, to be the master builders again. I mean my daughter is an architect and I keep telling them, “Your generation has to fix this. You guys need to be in charge again.” Joe Lstiburek, Building Science, green building, Sustainable building, green building expert, green building expert, ASHRE, LEED, problems with LEED

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 offormaldehyde 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?

Inhabitat: Sure.

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.

Joe Lstiburek, Building Science, green building, Sustainable building, green building expert, green building expert, ASHRE, LEED, problems with LEED

Inhabitat: You have been successful in taking complex building dynamics and making them relatively simple to understand. Do you think that building science is less complicated than a lot of folks out there are making it sound with a lot of hemming and hawing?

Joe Lstiburek: It’s a lot less complicated than people say and my only observation is there’s a lot of money to be made in keeping the peasants confused. I mean it’s so easy. What drives me crazy is WUFI models and computer simulations. None of that is necessary, and most of it is done wrong anyway.

I spend most of my time, and my firm spends a lot of time debunking other people’s reports, saying, “You can’t possibly be saying this based on what you did. The problem is the wall is leaking because you don’t have a flashing. Your hygrothermal model has nothing to do with why this wall is wet.”

Inhabitat: They couldn’t see the trees for the forest.

Joe Lstiburek: They couldn’t see the water through the trees.

Inhabitat: There you go. It sounds like, especially when we start talking about air barriers, you just do that right than you solve a lot of the other problems. You made a good living on buildings having lots of moisture issues.

Joe Lstiburek: It’s been a hell of a good life. I get to spend the entire winter in Aspen. Are you kidding me? The key to spending your entire winter in Aspen is to find a woman to love and marry, stay married to her, and get into fixing buildings. You need both.

Inhabitat: Good advice for the upcoming engineers who read this. So what’s the take away? Is it that air barriers are the biggest thing we need to focus on?

Joe Lstiburek: Well, no. Look, if I was in charge of teaching architects building science becomes very simple. Building enclosure is an environmental separator. You want to keep the outside out and the inside in, except when you want to bring the outside in and when you want to have the inside out. That’s it and there are certain rules on how to do that.

I have this little list of rules and it all can be distilled into we need a water controlled barrier, an air controlled barrier, a vapor controlled barrier, and a thermal controlled barrier. Then we need a method of exchanging the inside with the outside based on when we want to. That’s it, there are sub-rules on how you do this, but that’s fundamentally it.

And I would have loved to written my own LEED standard. It would have been a paragraph long and it would start off by saying, “Don’t do stupid things,” and, “Do this,” and we’re done. “And measure everything,” because if you can’t measure it, I don’t believe it.

Inhabitat: Are we looking at a climate specific design?

Joe Lstiburek: Oh, I don’t believe that. The wall-roof foundation assembly that I laid out works everywhere.

If you are doing poor assemblies you have to be very careful climatically, but a good assembly works everywhere. The irony is that the crappy assemblies are very climatically sensitive. The good assemblies are climatically robust.

Inhabitat: So, does that mean state-of-the art is that we can find wall systems that can be translated to work in almost any situation.

Joe Lstiburek: I have a little bit of fun with this. I teach at the university now and I no longer fail stupid students because that would be discriminating against stupid students. I say, “Look, I have to pass you. You’re an idiot. I can’t fail you, but I’ll make a deal. Promise me this – that regardless of where you end up and how long you practice, you’re only going to use this wall design, and this roof design, and this foundation design, because they work everywhere.”

Inhabitat: And forever.

Joe Lstiburek: And forever. Quite frankly, that is true.

Inhabitat: So you feel confident that building science is at the point now that we can build a quality envelope that we’ll feel comfortable with 40 years from now. We go back, we tear that thing up, we’ll feel that everything’s done what it needs to?

Joe Lstiburek: Oh, we were able to do that 50, 60 years ago. The answer is yes, we’re able to do that now and we were able to do that before I was born. The irony is that even though that information has been known for so long, it’s not been used. And my observation on that is that people don’t use stuff until it becomes impossible for them to not use it. In other words, things become intolerably bad before there’s a change or an intervention. It’s only recently that things are becoming intolerably bad enough that we have to intervene and fix, even though we knew or some folks knew how to avoid the problems 50 or 60 years ago.

None of this is very complicated, none of this is a big mystery. What’s happening now is that we need to get this information into the people who need to make the decisions in an informed matter. In other words, people aren’t inherently bad. They just don’t have the information they need at the right time to make the right decision. So this is an information issue as opposed to a research issue. We don’t need to do anymore research. We need to do better transfer of what we know to the people who need to make the decisions at the right time.

Inhabitat: So where is that information now? What are the sources for working professionals to tap into this in a meaningful way?

Joe Lstiburek: Well, NIBS, National Institute for Building Science has got a group called BETEC and they’ve got some phenomenal design stuff online. I mean I hate to brag, but our website is pretty darn good. And it’s for free –actually not, you’ve already paid for it. A lot of that work came out of government contracts that we were paid to do.

The National Research Council of Canada and Canada Mortgage and Housing Corporation have fabulous information online. The Department of Energy, USDoE, has got phenomenally good information online. And by and large, it’s fairly consistent. There aren’t big differences and wherever there is a big difference, just agree with me.

Inhabitat: Very good.

Joe Lstiburek: That was a bit of humor there, but you’re not laughing.

Inhabitat: I’ll write, “Ha-ha,” in there.

Joe Lstiburek: The big questions have been answered consistently well by all of these groups and there are issues in the margins, but they’re not big issues.

Inhabitat: When you go on the DoE web site there’s like 400 links or something like that to the energy software available, energy modeling software, for instance. Now, is any of this stuff really –

Joe Lstiburek: Useful? No. No. No.

Inhabitat: Everybody is wishing to have that magic bullet software?

Joe Lstiburek: Well, I view it as in love with Star Trek. I blame it all on Star Trek. Spock could go into that shuttle bay with his tricorder, do a tricorder scan and figure out that the tachyon field was interfering with the dilythiam crystals, causing him to off-gas, which is why Uhura has a headache. F**k that. We can’t measure s**t like that, but we believe that we can measure everything.

Watch NCIS and Abby Sciuto, that babe in the lab – you know, freaking does magical things and measures s**t and she does it all in 45 minutes, not counting commercials. It’s that we couldn’t do in 20 years even if we had unlimited money and people think that you can simulate and measure stuff. The world is not that clean and neat.

The best way we learn all of this is to build it and you see what happened. You say, “Ah, this worked. This didn’t,” and that’s the best education or information. That information lies in the experience base of the older engineers, architects and contractors.

One of the biggest problems we have is what I call our own institutional memory. We do a lousy job in construction, engineering and architecture, passing on the lessons of one generation to the next. So we are this huge, dysfunctional family. We need a Dr. Phil to get us all to talk to one another, or an Oprah, or somebody.

Inhabitat: It’s amazing how many times you refer to the fact that you would hypothesize something, come up with it and find it – it was in the books in the ‘50s and the ‘40s and the ‘60s.

Joe Lstiburek: It’s funny. I am one of the most frustrated, egotistical engineers on the planet. I thought I was a clever, smart guy who figured out stuff and it turns out that nothing I’ve ever thought I figured out did I actually figure out. It had been already done – better, earlier, more elegantly by not just one person, by lots of people. And we’re having all of these same discussions and arguments over and over and over again.

You know what? I feel like Bill Murray in Groundhog’s Day, except I don’t have an Andie MacDowell.

+ Joe Lstiburek


+ Building Science Corporation

Photos © Andrew Michler for Inhabitat