Vapor barrier behind shower
House is in Kansas City, Mixed humid climate.
Shower has 2 outside walls.
The old shower was tile, mastic on green board. Completely rottened out.
Being replaced with interlocking 4 piece plastic unit, Sterling Vickrel.
The walls have unfaced FG bats. Then blue board (I am guessing 1/2 or 3/4. Then T1-11 style panels.
Now on the long wall only the inside faces of the stud sides show water damage. But the bottom plate show water damage over the whole area.
The back wall comes down and a seat was built in. The seat was rotted and full of carpentary ants. But the outside wall behind it does not show and water damage.
So it appears that there is no condensation in the walls.
Now I am wonder what the best options are for moisture control.
The backwall will be built out about 7″ so I can put DW over that first and seal it off.
Don’t know if there is better option on the long wall then just going back with unfaced FG.
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
Replies
Bump.
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
Blueboard that thin has a relatively high perm rate, I forget what it is though, so I would probably do a plastic film over the fiberglass. There is a lot of moisture generated in the shower that should not be saturating the fiberglass.
The problem is that there is no way for it to dry out with the poly.And the poly won't cover the whole wall. Just that part the size of the shower walls. The whole wall is not being torn out. So it won't bee sealed that well.But then with the plastic shower walls there won't be that much of way for it to dry to the inside anyway..
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
>>But then with the plastic shower walls there won't be that much of way for it to dry to the inside anyway.Or vapor/moisture to get into the cavity at that level.What moisture/vapor source are you looking to control?
"Ask not what the world needs. Ask what makes you come alive... then go do it. Because what the world needs is people who have come alive."
Howard Thurman
Well there is the question of about how well the show walls will get sealed to the drywall. I will try my best but I would like a system that is a little more forgivable.But I don't see any option.Clearly the old system did not have the slightest concern about it.The seat bottom with plywood, with wonder board. And the back and skirt where green board with tile.ABSOLUTELY no water "proofing" other than the tile itself. And specially on the seat it just soaked in..
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
That's what I'm saying with the blue board, I think it can still dry to the outside, IF moisture got into the walls, which it shouldn't if you do a good job sealing the VB.
But either way I bet it will be fine.
Blue board will let gaseous vapor through.But if you do get any condensation then you have liquid water and it will get absorbed in the framing.Now if you only have say a teaspoon worth happening one time in the winter it will slowly evaporate and dry out.But if you say get a teaspoon a week for 3 months then it get saturated and never dries out..
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
Gotcha. Sound like you better leave the VB off then.