vapor barrier

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.

Word History and Origins

Origin of vapor barrier¹

First recorded in 1940–45

Example Sentences

The house, built prior to World War II, had no vapor barrier under the concrete.

From Seattle Times

The current price to install traditional fiberglass batts and a plastic vapor barrier is $3,917.

From Seattle Times

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

Washington’s code also requires a 6-mil vapor barrier for ground covering.

From Seattle Times

The protections will kick in at 52 degrees for those who wear vapor barrier clothing or chemical resistant suits, for example.

From Seattle Times