Published on January 29th, 2013 | by Henri0
Clarifying the problems caused by housewraps
Q. I did not completely understand your recent article about the use of housewraps that appeared in the Star Ledger today and it attracted my attention. My daughter is currently in the process of putting up new siding. They did use Tyvek, and as far as I understand, they applied it directly to the existing wood exterior.
If I am reading the previous question correctly, the person wanted to know if applying Tyvek to the plywood was going to cause damage to the plywood. May I ask if this is what you are referring to in your answer? After reading and re-reading your answer, I have to admit I’m confused. It seems to me that you are addressing the problem of having the housewrap in direct contact with the underside of the exterior siding, but what about it being in contact with the plywood, or as is the case in my daughter’s situation, being in contact with the original wood exterior?
I certainly would admit I’m a novice about issues such as this, and your answer may well be addressing the writer’s question, but I’m not getting it, so if you wouldn’t mind explaining it a bit more I’d be most appreciative. Perhaps the simple answer is that you should never attach housewrap directly to wood, whether it’s the plywood or the underside of the exterior siding?
A. Sorry that my answer was not clear enough in that earlier column. I’ll try to do better this time. Tyvek or any other housewrap, or felt, is applied directly over wood sheathing (plywood or OSB). But what I was trying to say is that wood siding should never be applied directly over any housewrap. That’s where the problems begin.
Your daughter has one very easy option: have Benjamin Obdyke Home Slicker installed over the housewrap, and the wood siding installed over the Home Slicker. It forms a drainage plane and a ventilation space between the siding and the housewrap.
But why use housewrap with plywood? Why not use No.30 felt? It’s less expensive and less prone to problems. Even if she chooses to use felt, though, she should still use Home Slicker.by