How to Waterproof a Flat Roof Skylight

Using a straight edge and pen mark diagonally from corner to corner to form a cross and cut with a pair of scissors

Position the skylight over the opening. If the skylight is already in position prior to installing the rubber membrane the rubber membrane can be cut and then either lifted over the skylight upstand or an additional cut made to the nearest membrane edge.

Cut Back Excess Rubber a minimum if 75mm from top of skylight

Apply contact adhesive to skylight upstand and back of rubber membrane

Bond EPDM rubber membrane to skylight upstand once contact adhesive is touch dry

Cut 9" Elastoform to size and mark position on skylight corners

Apply Rubber Primer

Ensure rubber primer is touch dry before installing Elastoform tape

Install Elastoform starting at the top of the skylight and working downward stretching the tape as necessary

Apply pressure using seam roller

The 6“ Cover tape can be used to join the rubber membrane to the skylight upstand if flashing kit is not provided with the skylight. Cut to length ensuring a minimum 3 ” wrap around on corners

Apply Rubber Primer

Install 6“ Cover Tape. The tape should be installed equally on to the rubber membrane and skylight (3” on each) and apply pressure using Seam Roller. Lap Sealant can be used on the edge of the tape if necessary

Completed Skylight Installation