Cold Flat Roof Vapour Barrier

Applicability limited to very cold subarctic and arctic regions.

Cold flat roof vapour barrier.

Do i need a vapour barrier between the plasterboard and the bottom of the joist. Room in the roof constructions often use a combination of warm and cold roof constructions with varying types of insulation. The notion behind a vapour control layer is to install it on the room. Condensation within a flat roof mainly occurs during cold weather when moisture vapour in the air which has been generated within the heated building rises from the room below into the cold roof void above the ceiling.

When the temperature of the vapour falls to or below its dew point the water vapour condenses on cold surfaces. This wall is a further variation of figure 6 but now it has a class i vapor retarder on the interior a vapor barrier completely eliminating any inward drying potential. A vapour control layer helps you shield your building from the consequences of condensation condensation is generated when warm moist air rises and condenses into a liquid on contact with the cooler areas above the insulation. A vapour control layer or vcl on a warm flat roof sits between the roof decking and the insulation.

Cold roof areas usually include vapour open fibrous insulation e g mineral wool quilt. A flat roof vapour barrier such as iko s mvp modified vapour protector offers appropriate moisture protection. Flat concrete roofs are generally not ventilated since the ceiling internally is generally a plaster and skim coat directly to the underside of the cold concrete. Bituminous vapour retarders asphalt mixed with felt or fiberglass or non bituminous vapour retarders plastic.

Including fibreglass roof kits torch on felt and liquid rubber products everything you need for flat roofing is in one place. Creating a void between the old ceiling and new is better but ideally you need to eventually consider insulating the top of the concrete roof with solid insulation and a better. Flat roof vapour barrier materials when constructing a flat roof there are two types of materials commonly used. Any advice would be great.

Including flat roof vapour barrier for extra secure roofing solutions. The sloping ceiling areas include closed cell or foil backed rigid board insulants most of which are highly vapour resistant. I am building a cold flat roof on an extension.