Vapor retardant paint clarification question
Hi, folks. Can someone clarify for me a question concerning vapor retardant paint and whether it is to be applied on the [U]inside[/U] walls of the house as a way of keeping moisture from migrating to the blown cellulose insulation? I have the option to add such insulation to my 100 y.o house as part of a federal weatherization program. I won't do it if there's danger of moisture entrapment, but someone replied to a thread I posted yesterday about this, saying I could use vapor retardant paint. I asked in that thread for clarification about what surface it should be applied to, but no one has replied to the question. Thank you!:)
Re: Vapor retardant paint clarification question
Most of us only visit this page once a day or so. we are volunteers, not staff and anything said here is our opinion so it would be good if you checked other references. I would not be offended if you checked with other sources.
I just answered this on your other post. But let me add one more thing. Since this is just like a regular paint job, it does not have to be done immediately. In fact since it is almost spring, you can easily wait until this fall. Also your house probably has a lot of ventilation to the outside so the vapor barrier doesn't have to be as tight as it would need to be in a new house or if they "tighten up" the exterior cladding on you house. As long as the wall breaths better to the outside than it does tot he inside, you will be OK.
From you description, it sounds like they are doing a damp spray insulation. This is good. It would help if they leave a slight air gap between the insulation and the exterior. Usually they just remove a clapboard near the bottom and near the top, drill holes in the substrate boards and blow in loose fill through those holes.