Vapor Barrier For Metal Roof

Single bubble vapor barrier acts as a reflector.

Vapor barrier for metal roof.

It is therefore suitable for most roofs. Build your structure where possible in an elevated position with good natural drainage place a vapor retarder under floor gravel or concrete ventilate enclosed building when concrete is being poured and continue to ventilate until it is cured use heaters that are vented to the. This reflection of the heat eliminates the temperature difference that causes the metal to sweat and drip. A 90 mil sbs modified asphalt base sheet can be used in multiple ply systems as an air and vapor barrier or a temporary roof for up to 60 days.

In this example although roofs and walls both need similar water vapor barrier properties the roof barrier often needs to be either inflexible or air permeable to prevent being blown away in an updraft caused in a storm. Single bubble vapor barrier acts as a reflector. Used as an air and vapor barrier direct to metal decking. A roof design that includes an adhered roof membrane with multiple layers of insulation with board joints offset and staggered over a vapor retarder air barrier helps lower the risk that air and the moisture it carries will infiltrate the roof system.

A roof vapor barrier needs to have different properties to a barrier in a wall or one used to prevent radon permeating through a floor. Resistant to foot traffic the engineered composition of v gard provides high resistance to static loading and dynamic impact. V gard provides an excellent vapor barrier with a vapor resistance value expressed by an sd equivalent air layer thickness of 1 500 m. This reflection of the heat eliminates the temperature difference that causes the metal to sweat and drip.

That reduction of air and moisture infiltration can then help improve roof longevity. As the sun s ray heat the steel the heat radiates through the metal but is reflected back out of the roof by the foil side of the vapor barrier.