Menu

Pooling water on flat roof London Ontario

This week we were in the North East end of London Ontario working on a flat roof. This was a bit of a different scenario than we normally face. We were called in not because a client had a flat roof that was old or leaking, we were called in because a client had a flat roof section that had a large amount of water pooling on the roof and wasn’t shedding water.

On top of that the flat roof had a deck built over the top of it, so with such a large build up of water there were mosquitoes living and breeding in the water, so the client could never enjoy their deck during warmer weather. They were also concerned about other bacteria growing in the water.

Our plan was to shed the water from the wall side, there were 3 scuppers already at the other end of the roof, so we sloped the roof towards those so there is no more pooling water on the roof. We also noticed that the scupper was sitting higher than the level of the roof surface, which is never a good thing.

We had to remove the entire deck and railing, you can see how much water was sitting on the roof, there was so much it couldn’t even evaporate which normally happens 2-3 days after rain. We also removed some siding and flashing so we could get the membrane up under the siding and up the wall.

There was a single ply membrane, our plan was to poke some holes in it to allow moisture and hot air to escape so there isn’t condensation on the inside of the home, in the end we decided to remove all of the single ply just to avoid that condensation risk.

We created a taper towards the drain by using half inch fibre board doubled up and then tapered off. We installed a new scupper so the water was diverted and handled by the scupper. Then we installed the base sheet and cap sheet for a water tight diversion of water.

The deck is up to the client, but they won’t have pooling water problems ever again!

Legacy Flat Roofing & Sheet MetalServing all of SouthWestern Ontario: Strathroy, Glencoe, Woodstock, Lambeth, Windsor, Belmont, Chatham, Sarnia, Wyoming, London, St. Thomas, Wallaceburg