Insight
Material View of Mold
By Joseph Lstiburek
Building Science Insight 027: last updated 2009/11/10
Mold is pretty easy to understand. No water no mold. Any questions? Well, there are a few. For one we have more mold today, but we don’t have more water. What’s with that? We’ve always built outside out of wet stuff. Concrete comes in a big truck and we “pour it.” We put “mud” in the joints of gypsum board. That hasn’t changed. The problem is that the same amount of water we’ve always had to deal with is hanging around longer and longer in building materials that can’t take it. We have more insulation today and that reduces drying potentials because it reduces energy exchange. That is one reason we have more problems with mold today. The “more insulation” is responsible for the water “hanging around longer” part. But there is another reason—the building materials “that can’t take it” part. We used to build out of rocks and 1,000 year-old trees. Not any more and that is a big deal, as we will see. More >>
