Posted 2010-07-01 3:59 PM (#121808 - in reply to #121807) Subject: RE: polyso or polyiso insulation
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Location: Northern Utah
A vapor barrier is easy to add. In new homes that we build we stretch a sheet of visqueen over the walls after we put in the insulation. But the insulation companies admintly proclaim that it's not neccessary. Their claim is that the latex paint we put on the walls is actually a better vapor barrier. The test numbers they provide shows more moisture passes through an electrical outlet hole ( 2" x 4") than will pass through an entire 4x8 sheet of sheetrock with paint.
Is the Polyso a spray foam or is it in a rigid foam panel. Either way, Install it and cover the surface with the vapor barrier of your choice, Plastic, kraft paper or a good quality paint. The point being, that more moisture will come through the outlets, swtichs and doors than ever will come through the material itself. Horse trailers just are not sealed up that tight and people just don't go inside and stay for days at a time. You open and close the door too often to worry about moisture passing through the walls.
Posted 2010-07-01 4:32 PM (#121811 - in reply to #121807) Subject: RE: polyso or polyiso insulation
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Thanks Painted Horse. This is rigid 2 x 4 sheets. It's being removed from some buiding and we're buying some to insulate the workshop and barn so I was wondering if I could use it in the trailer too.
It sounds like it will work OK. So there doesn't need to be anything placed between the metal wall and and the insulation?
Posted 2010-07-02 10:27 PM (#121846 - in reply to #121807) Subject: RE: polyso or polyiso insulation
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Location: Northern Utah
As I suggested you will have more vapor pass thru the door everytime you open it, than what will pass through the walls in hours. You will be more concerned with Condensation of moisture that is in the trailer condensing on the walls without some type of insulation.
Posted 2010-07-03 9:55 AM (#121858 - in reply to #121846) Subject: RE: polyso or polyiso insulation
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Location: Minneapolis, MN
Originally written by Painted Horse on 2010-07-02 10:27 PM
As I suggested you will have more vapor pass thru the door everytime you open it, than what will pass through the walls in hours. You will be more concerned with Condensation of moisture that is in the trailer condensing on the walls without some type of insulation.
The area of a LQ trailer is so small that a couple people breathing can create too much moisture when the windows are closed....like when heating.
Posted 2010-07-03 10:08 AM (#121859 - in reply to #121807) Subject: RE: polyso or polyiso insulation
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Location: Northern Utah
And that's exactly my point. Whether you do or don't have a vapor barrier is not going to make a difference. Since the moisture is coming from other source vs passing through the wall.
Posted 2010-07-03 11:33 AM (#121860 - in reply to #121807) Subject: RE: polyso or polyiso insulation
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Thanks. I was wondering if trapping the condensation between the wall and the insulation would cause a problem-like keeping the metal wet or creating a mildew type of problem.