|ric knows paint
||05-03-2012 07:53 AM
Originally Posted by Nailbags
So I have a customer that after i finished their sheet rock wants me to do the painting for them I told them sure it will be time and materials that said. I went and bought the primer To lay down before I do the orange peel texture. Then shoot a second coat of primer over the the texture. I come back with it and he asks why not PVA primer it is cheaper and acts as vapor barrier. I have never heard such a thing i told him my time is money and If you want me to return the primer I will charge for my time and mileage. he was cool with that. But I told him I would pick up in the morning. So any pros out there with any insight as to the validity of his statement?
Although most people here don't agree with me regarding PVA primers and their viability in the overall painting scheme, I think it'd be a really far stretch to suggest that any PVA could perform well as a vapor barrier, if at all...
But a better question might be why is a vapor barrier important to your customer? Actual vapor barriers makes sense for below grade walls, but if you've got issues above grade regarding moisture/vapors, there are far better, more effective, ways to deal with that type of problem...Years ago, I seem to remember Zinsser advertising that a vapor barrier could be created by using BullsEye 123 on outside walls, and BIN on inside walls. The problem with a system like that is if you have a moisture problem within your home, it's possibly the result of over-insulating - moisture must be able to escape your home, and if you block all paths of egress, this same moisture will reveal itself in some other form within your home such as fogged up windows, doors and windows that don't shut properly, nailhead popping & rusting on trim, mold/mildew growth, curious infestations of insects attracted to damp wood...did I mention mold/mildew growth? (...and all this is just to keep the moisture, inside the house, from escaping - a completely different set of problems exist if you're trying to keep outside moisture from coming in the home)
I realize I've illustrated kind of a worst-case, end of the world, scenario...but I have seen homes that were so over insulated that all these conditions were present...Care to guess who the homeowners tend to blame for these problems?
But, a PVA drywall primer as a vapor barrier? I don't think so...