Central London Ontario Flat Roof Ponding & Drain Repair

Hey everyone! It’s been a long winter so we haven’t been posting as many videos, we tend to just want to stick to getting the projects done and get out of the weather!!

This week we were in Central London Ontario, at a residential home.

An interesting little project today, there is a flat roof at the back of the home that has been ponding a lot of water, and causing some other issues, so we were called in to get the flat roof back into shape.

There’s a few details to content with, there was a rooftop AC unit, a dryer vent stack, there is a door threshold that needed to be sealed, and as you can see in the video, the roof drain is sitting a little too high, which is the key issue the roof keeps ponding.

Our plan is to raise the perimeter of the roof slightly using fibreboard and asphaltic board on top of that, and then we are going to sump the drain – meaning we are going to lower it so the water can get off the roof effectively as the homeowner was experiencing other issues with the ponding.

We added a polyurethane sealant to the door threshold, then we tackled the roof itself by elevating the border of the roof as you can see in the video, then we put down the substrate and base sheet.

Because we were retrofitting an existing drain we added a u-flow connector. As we are using two different connectors inside the drain we need to make sure there is no ability for that seal to be compromised, or if water gets backed up that the pressure will force water in between the connection. Now if the roof drain gets backed up, it will only come out onto the roof, and nowhere it shouldn’t!

As always, to give the roof a nice look, and to add some extra water shedding ability, we finished off the roof with some metal flashing.

If you ever need any help on your flat roof in the South Western Ontario area shoot us an email!