Air sealing and insulating an attic floor and then providing proper ventilation measures to the roof is a time tested and superior way to insulate most homes. This video shows how cellulose insulation allows water from a roof leak to dry out without causing any rot or attic mold problems. This is able to occur because cellulose insulation is hygroscopic, meaning that it easily absorbs water, but also just as easily releases it, and the leak is not severe enough to penetrate all the way through to the drywall below. The ventilation in the roof is also adequate to permit the cellulose to easily dry once it stops raining. Assessing attic ventilation requirements and adding or balancing it when necessary is part of every attic insulation job that Insulwise performs.
We contrast this to what can happen when the underside of a roof is insulated with spray foam, in particular open cell spray foam. The leaks are much more difficult to find, and the result is that if you do have a leak in your roof, you are more likely to have roof damage to contend with as a result. We have seen roof sections rot before that had been sprayed with open cell spray foam. Closed cell spray foam (far less commonly used in our area) is however a viable solution for insulating the underside of a roof, but it is FAR more expensive than open cell foam, so the spray foam guys here rarely try to even sell it.
2 окт 2023
