See how to connect an old roof drain to a rubber membrane a quick and easy way. Making a transition to a drain after a rubber membrane is installed, is not always easy. There are many methods. The common method is to use the ring clamp that comes with a new drain to clamp the rubber membrane down. But if you are using the existing drain on the roof, then you will not always find a clamp to make the transition. I use a polyurethane-based product from Bergstrom Industries called Turbo Poly Seal. This makes it very easy to tie a rubber roof to an existing drain.
It is not necessary to remove old cast iron roofing drains. For the most part, they are in good shape. The hard part is to remove all the tar buildup that people have used to seal the drain. Once the drain is clean, then the method in the video above can be used to tie a drain with a rubber membrane.
You can also use this same method to make repairs on a drain. Make sure you remove all the tar buildup. This is the hardest part and it is messy. Preparation is more important than doing the actual repair. Once you got the membrane clean and the drain, then you can use the Turbo Poly Seal with fleece to make the necessary repairs.
0:00 Transition of Roof Drain to membrane
1:00 Cutting membrane around the drain
2:00 Cutting Tabs in the fleece
2:30 Applying 1st coat Turbo Poly Seal
3:20 Embedding Fleece into Turbo
3:38 Applying 2nd coat Turbo Poly Seal
5:26 Final looks
5:41 Embedding ceramic granules
7:00 End