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Building Safety Month?

TMurray said:
When reading Conard's post, I am curious where the vapour barrier layer is located within the walls. We have been using vapour barriers on the inside of buildings for years (more than three decade) and have very tight construction (I've tested houses built in the 80s that have an ach of less than 0.3 at 50Pa). I've seen walls opened up for renovations and remodels and the only places mold has been a problem is if a double vapour barrier is installed. Now, since I'm in a heating climate, the inside is the right spot for my vapour barrier.
You open up the whole can of worms related to all the building failures we've had. You can't have a dual barrier so you have to choose the side that is going to be your vapor barrier, if you paint your interior walls that decision is made for you, it has to be the interior, and if you put wall paper on walls it really has to be the interior. Our problems stemmed from sheathing sealing up the exterior, back when I started in the days before plywood 1x8 green sheathing worked because the walls breathed through the gaps and knots, with our seismic codes our engineers started requiring plywood shear walls, sealing up the exterior creating the dreaded dual barrier. At first (in the 70s) I got permission from my engineers to put the sheathing on the interior so the walls could continue to breathe out, as the engineers started requiring so much Simpson steel and red iron moment frames I recently figured out that a full red iron steel frame would be just as economical, allow me to have walls of glass (as Californians want), eliminate sheathing and the dreaded dual barrier. To touch on another of your points, even the Canadian Building scientist, Joe Lstiburek, says that you only place an interior poly vapor barrier in the coldest of climates, about 1% of the United States.View attachment 2270You especially don't want to put a poly vapor barrier in any home with air conditioning, air conditioning creates a cold interior wall and the poly becomes a condensing surface loading any hygroscopic bulk insulation with moisture rotting out even walls that can breathe to the exterior. If you have rot you have mold, if you have mold you have sick people, if you have sick people you have lawsuits. I won't even go into the chemical problems of newer building materials making people sick and lawsuits, suffice it to say that the problem is so bad that California has tripled ACH pretty much defeating any building sealing, now ASHRAE 62.2 has about tripled ACH, this is going to mandate expensive ERV and HRV systems. When our Building Standards was considering mandating fan systems to evacuate chemically laden air I wondered at the time why Panasonic was spending the millions it was to sell a few $100 fans, now I know, it wasn't $100 fans, it was $10,000 HRV or ERV systems statewide.View attachment 5453

View attachment 5453

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mark handler said:
"coldest of climates, about 1% of the United States"Not this year....
Yep, I've even read some climatologists are saying we are going into a new ice age, others that only for another 35 years. What would we do if it got as cold as Canada here, move to Mexico?
 
TMurray:

One of my old roofers died, another of my old roofers just called to be sure I was aware and would be attending Chuck's services, I asked what he was doing now and he said he is just maintaining a skeleton roofing crew to maintain credibility for litigation, he says the mold claims in these sealed up buildings are way more profitable than roofing anymore, he is now netting $150,000 a month (that's $1.8 million a year net profit for those mathematically challenged) writing reports and testifying against the architects and builders who built sealed up buildings, and he only testifies on roofing failures. He says this OSB is an unmitigated disaster, as soon as there is a pin hole leak mold starts growing and there is disaster. So keep sealing them up and requiring that they be sealed up, it will keep us old guys doing expert work in lots of pocket change as long as we want or need it. Since I am older than he is (and I'm a builder rather than roofer) he actually asked me when we started sealing up buildings and why we did it? Hmm, I wonder if the construction defect attorneys can name the guys who do the blower testing to insure that there is no air circulation in walls and roofs and the AHJs enforcing this code? Keep sealing them up, we old guys need the money.
 
conarb said:
TMurray:One of my old roofers died, another of my old roofers just called to be sure I was aware and would be attending Chuck's services, I asked what he was doing now and he said he is just maintaining a skeleton roofing crew to maintain credibility for litigation, he says the mold claims in these sealed up buildings are way more profitable than roofing anymore, he is now netting $150,000 a month (that's $1.8 million a year net profit for those mathematically challenged) writing reports and testifying against the architects and builders who built sealed up buildings, and he only testifies on roofing failures. He says this OSB is an unmitigated disaster, as soon as there is a pin hole leak mold starts growing and there is disaster. So keep sealing them up and requiring that they be sealed up, it will keep us old guys doing expert work in lots of pocket change as long as we want or need it. Since I am older than he is (and I'm a builder rather than roofer) he actually asked me when we started sealing up buildings and why we did it? Hmm, I wonder if the construction defect attorneys can name the guys who do the blower testing to insure that there is no air circulation in walls and roofs and the AHJs enforcing this code? Keep sealing them up, we old guys need the money.
The more I read about energy efficiency in cooling climates the more I think that someone just took the rules we use in heating climates and started using them. Attic ventilation is a requirement here to help prevent ice damming. Walls are required to be vapour permeable to the exterior. moisture sensitive products (like OSB) are discouraged in high r value & tight assemblies. These are all things I know because we've grown up with these problems and when I hear someone talk about the stupid things that the various energy codes require and the problems that have resulted I think: "we'll yeah, you shouldn't do that in that climate". Maybe we should stop adopting codes that are developed at a national level without amending them to work in our areas first. But, maybe that's just wishful thinking.
 
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