125 mu BLACK VAPOUR BARRIER POLYTHENE 4mx25m 500g

4x25Mtr Polythene vapour barrier in Black

Thickness

125mu (500 Gauge)

Intended Use

Vapour resistant layer in the construction of walls and ceilings
• Slip layer
• Protection of the thermal and acoustic insulatiion from moisture
• Temporary protection of roof surfaces
• As temporary glazing during construction

THE APPLICATION OF VAPOUR CONTROL LAYERS IN BUILDINGS

A vapour control layer forms a barrier layer within buildings, which prevents interstitial condensation and thus simultaneously prevents problems from moisture and improves energy efficiency/comfort. It’s a vital component within the construction of buildings as water vapour can damage even the strongest building structures. A good vapour control layer helps to maintain the building quality and ensure effectiveness of insulation.Water in its gaseous state becomes water vapour which is totally invisible. This then diffuses through buildings from the warm interior of a household towards the cold exterior. As water vapour passes through the walls of buildings and meets a surface below the dew point (being when water vapour condenses), it becomes condensation which poses a threat to the effective of insulation and can damage building structures.

Where are vapour control layers installed?

A vapour control layer, or vapour barrier, is installed in or along walls, ceilings, and floors on the warm side of the insulation to resists moisture from the warm side getting into the insulation. Any tiny amount of vapour within a wall cavity evaporates outside due to cooler external air, which makes it especially important that any paints or potential barriers are removed to allow this evaporation process to occur.