A self-adhesive vapour control layer is an important step when installing a roofing system. In this article, we will go through each step of installing a VCL.

Firstly, what is a self-adhesive vapour control layer and what is it used for? A self-adhesive VCL is a membrane that is designed to be used as part of a built-up roofing system to protect buildings from developing condensation and mould. VCLs stop moisture passing through walls, roofs, and ceilings. They are also sometimes referred to as vapour barriers. So, as the name suggests, they create a barrier against vapours. The self-adhesive aspect makes application simpler and risk free. Flames are not needed, so application is safe and convenient and low risk.

The Wonderbuilds Self-Adhesive Vapour Control Layer (SA VB 600) has a reinforced aluminium upper surface finish, and a silicone release film lower surface finish. It can be used on plywood or metal substates, and on concrete substates where required. It has been designed to be used for buildings that have high levels of moisture, such as swimming pools. This product must be used in conjunction with the Wonderbuilds SA (self-adhesive) Primer.

Below is a roofing system that includes the Wonderbuilds Self-Adhesive Vapour Control Layer (SA VB 600). This system has a 25 Year Guarantee and is safe to torch. It also includes a BROOF (t4) capsheet and underlay.

The following products are included in this system:

1. Wonderbuilds BROOF (t4) Capsheet 8M
2. Wonderbuilds BROOF (t4) Underlay 10M
3. Wonderbuilds Bitumen Faced PIR Insulation
4. Wonderbuilds PU Insulation Adhesive
5. Wonderbuilds VB600 Self-Adhesive VCL
6. Wonderbuilds SA Primer

Detailing:

1. Wonderbuilds BROOF (t4) Capsheet 8M
2. Wonderbuilds BROOF (t4) Underlay 10M

Self-adhesive vapour barriers can be installed by following the steps below:

You will need the following:

• Self-adhesive vapour control layer
• SA Primer
• Tape measure
• Utility knife or scissors
• Silicone roller

Step 1: Prepare the area by making sure that it is clean and dry, and free of debris.

Step 2: Measure the area, then add an extra 10cm for side and head laps.

Step 3: Use the utility knife or scissors to cut the VCL. Make sure that it is cut to the precise measurements needed.

Step 4: Peel the backing off the VCL and pressure roll on to the substrate, pressure rolling into place will stop any bubbles forming in application, starting from one end, and moving to the other to allow for a straight and level application.

Step 5: Pressure seal all side and head laps using a silicone roller. This is to stop penetration of moisture.

Step 6: Finally, adhesion to all areas.

Always check the manufacturer’s installation guide for the best results.

In conclusion, self-adhesive VCLs are an essential part of an insulated BUR system, or any insulated system that requires a vapour barrier. Wonderbuilds VB600 can also be used as a preparation layer under Wonderbuilds LiquidGuard PU Liquid, when liquid is being applied to a insulated system.