vapor barrier

American  

noun

Building Trades.

1. a layer of material, as plastic film or foil, used to protect installed insulation by retarding the transmission of moisture from the interior environment.

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Etymology

Origin of vapor barrier

First recorded in 1940–45

Example Sentences

See Examples For:

vapor barrier

Nicholson & Galloway, an exterior restoration contractor experienced with historical domes, repaired cracks in tiles, patched concrete, then layered on new protective materials: a hand-troweled vapor barrier, spray foam insulation, stainless-steel framing, plywood sheathing.

From New York Times ● Dec. 22, 2022

Murray says that if your basement is prone to moisture, you’ll want to apply an initial coat of vapor barrier, a thick, white paint that will seal masonry.

From Washington Post ● May 10, 2022

Be sure to install a high-performance vapor barrier over the pipes and gravel before pouring the concrete floor.

From Seattle Times ● Jul. 30, 2021

Another possibility, he says, is that the soil also provides a vapor barrier to help stifle sublimation as well as physical insulation.

From Science Magazine ● Aug. 16, 2017

The experimental uniforms, of which 150 have been tested, work on the "vapor barrier principle."

From Time Magazine Archive