This type of underlayment is critical to a quality roof installation.
Pole barn metal roof underlayment.
But a preinstalled membrane may be even more effective at removing condensation.
We ll add a vapor barrier so the moist air does not flow up through the insulation and condense on the roof.
Synthetic underlayment is a newer innovation that is taking over the metal roofing industry as a better more advanced replacement for felt underlayment.
Single bubble vapor barrier is designed to prevent such inside rain by keeping the metal from sweating.
Make sure the product is designed to be used under metal.
Underlayment and insulation.
In a residential application however condensation is a concern.
Fire retardant poly barrier double bubble reflective insulation is a durable layer of polyethylene bubbles bonded to and.
The problem with using.
Pole barn vapor barrier.
Synthetic underlayment is a roofing accessory created by weaving spinning together polypropylene or polyethylene and a polymer to form an all over protective barrier to put between the roofing material and the roof deck.
In a barn shop or other outbuilding you can attach your metal roof directly to the purlins.
In my case i planned to use osb on the sides and roof asphalt shingles up top and vinyl siding on the sides.
When hot roof construction is done a roof with no ventilation a breathable underlayment is recommended.
The underlayment doesn t really impact condensation in your case the condensation will just occur on it rather than on the metal itself.
Once again this is used on cold roof construction.
I live in an hoa and we don t allow steel buildings roofs.
Your risk is when warm moist air from inside hits the cool back side of the roof system.
It serves as a moisture barrier as well as a slip sheet.
This building will have a shed roof that will be difficult to ventilate well so it seems that the breath ability of felt paper would be good and would be more likely to be installed properly by a pole barn contractor but i have heard that the felt is a poor choice for metal roofs because of the heat and expansion of the metal.
I m looking at a pole barn with steel trusses made of 2 2.
Insulation and ventilation are going to be keys for you.
Moisture can collect on the inside of your metal roof whenever warm moist air inside your building meets the cold metal of your roof.
It will want to condense.
I m building a pole barn but don t wish any moisture underlayment for corrugated metal 4 18 2005 within the corrugated roof discussion of the residential metal roofing forum.
Metal roof condensation.