A vapor barrier is a low-permeability membrane installed within the roof assembly to control the movement of moisture vapor from the building interior into the insulation layers above. In commercial and industrial buildings, interior activities such as manufacturing, food processing, cold storage, or high-occupancy spaces generate significant moisture vapor. Without a properly placed vapor barrier, that moisture migrates upward into the insulation, reduces its thermal performance, and eventually causes structural deterioration in the roof deck.
Vapor barrier placement depends on your climate zone, building use, and roof assembly design. In most of the U.S., the barrier belongs on the warm side of the insulation. Getting this wrong results in condensation forming inside the assembly where you cannot see it. By the time interior signs appear, the damage to insulation and deck is usually extensive and expensive to address.
Sentry Roofing designs vapor control into commercial roof assemblies from the start. On reroof projects, we assess existing moisture conditions and specify the right barrier material and placement for your building type and use.
Ready to add this to your building? Request an evaluation from Sentry Roofing and we will put together a solution for your facility.
