Accessories Kalzip vapour control layer

Kalzip vapour control layer

Enhance the performance of a roofing system by incorporating a suitable vapour control layer (VCL).

A VCL will reduce the movement of water vapour from inside the building through the roof construction (thereby reducing the risk of condensation) and also assists in limiting air permeation through the system.

Kalzip VCLs are available as standard in either a clear three layer membrane for mid range applications or a foil encapsulated five layer membrane suitable for high humidity applications where a greater vapour resistance performance is required.

The VCL should always be installed on the warm side of the construction and should be continuous across its surface.  It must be fully sealed at all laps, perimeters and penetrations in order to ensure its effectiveness.

The type of VCL to be specified would be dependent upon the use of the building and therefore the condensation risk.

Humidity classTypical building typeKalzip VCL Liner/decking configuration 
    Solid liner Perforated liner sheet and
solid or perforated decking
1 Very low Storage areas Kalzip VCL foil with
one row of Kalzip VCL sealing tape
Kalzip VCL foil with
one row of Kalzip VCL sealing tape
2 Low Offices, shops Kalzip VCL foil with
one row of Kalzip VCL sealing tape
Kalzip VCL foil with
one row of Kalzip VCL sealing tape
3 Medium  Dwellings and low occupancy Kalzip VCL foil with
one row of Kalzip VCL sealing tape
Kalzip VCL foil with
one row of Kalzip VCL sealing tape
4 High Dwellings with high occupancy, sports halls, kitchens,
canteens, buildings heated with unflued gas heaters
Kalzip VCL foil with
one row of Kalzip VCL sealing tape
Kalzip VCL foil with
one row of Kalzip VCL sealing tape
5 Very high Special buildings e.g. laundry,
brewery and swimming pool
Kalzip VCL foil sealed with
two rows of Kalzip VCL sealing tape
Kalzip VCL foil sealed with
two rows of Kalzip VCL sealing tape

Notes:

1. The Kalzip VCL must be fully sealed at all side and end laps, penetrations and perimeter details to ensure the required level of air-tightness for the building envelope.

2. On humidity class 1 (very low) buildings where there is limited flashing details and penetrations it may be feasible to omit 
the Kalzip VCL. The Kalzip liner sheet should be fully sealed at all side and end laps, penetrations and perimeter in this instance.

3. Humidity Class of buildings taken from BS EN ISO 13788:2002 – Hygrothermal performance of building components and building elements

Internal surface temperature to avoid critical surface humidity and interstitial condensation – calculation methods.


Product Downloads

Please Register or  to gain access to locked downloads.

brochure image.jpg



English We have automatically detected your language settings