Vinyl Wallpaper
user-1075855
| Posted in Interior Design on
I’ve been trying to educate myself on vapor barriers since they are by far the most complicated topic I’ve ever come across.
One thing that kept popping up is the notion that vinyl wallpaper is bad (except for very cold climates). It is a vapor barrier and thus keeps the walls from drying to the inside, right?
Suppose I want vinyl wallpaper in a climate zone 4 or lower. Suppose I like the look of it, and I still want air conditioning. What can I do to make sure it doesn’t cause damage to the walls?
Thanks in advance for any help!
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Replies
J.S.,
If you must have vinyl wallpaper, you should choose an insulation that isn't air-permeable or vapor-permeable -- for example, closed-cell spray foam.
I have a related question about vinyl wallpaper. I understand that wallpaper on exterior walls is a poor/high risk choice, and probably worse in a full bath that frequently has high humidity. However, what about in a powder room/half bath that has only interior walls?
Thanks for your thoughts,
Andrew,
There is no reason that you can't use vinyl wallpaper on interior partitions.
Wow it's that easy! I was expecting you to say that the best way is to poke holes in the wallpaper.
Martin, how would closed cell foam help? Just like the wallpaper, it would be a vapor barrier. Would there not be condensation between the foam and the wallpaper? Two vapor barrier is supposed to be a bad, right?
J.S.,
With closed-cell foam, which is both a vapor barrier and an insulation material, there will be no cold surfaces that allow condensation. Nor will there be any opportunity for vapor to move through the assembly.
Oh I see. But what about where the studs meet the drywall and then the wallpaper? Just like thermal bridging, would condensation come through those points?
J.S.,
Softwood lumber has a high enough R-value per inch that the edges of studs are unlikely to get cold enough to cause a problem during the air conditioning season. In any case, lumber is hygroscopic, so condensation isn't really possible on wood; what happens is moisture absorption. (The wood gets a little more damp -- but it will dry out before the humidity becomes problematic.)
Oh I see. Alternatively, if I put a ton of vapor impermeable rigid insulation on the outside, would I be fine?