Displaying items by tag: roof repair

Toronto flat roof leaking drain repair

Sun, 13 Jun 2010 22:30:49 +0000

A Toronto client's flat roof was leaking during rains. During a roof inspection we noticed the rubber membrane around the drain was loose and lifting. We suspected water rushing towards the drain was running under the membrane. We repaired the area by applying a SBS 250 cap membrane patch.

When we removed loose membrane and cleared the drain area we saw that the area was wet, which confirmed our suspicions that it was leaking. Once the area was cleaned up we applied Bakor primer on the metal surface area of the drain to help the new rubber membrane stick once it is torched. We then applied a SBS 250 cap membrane over the area and finished off by applying Bakor plastic cement around the drain. Since it rained the next day we called our client to find out whether he was still getting a leak. As expected the drain area was the cause of the leak and our client was thrilled that it was no longer leaking.

Leaking chimney flashing

Tue, 11 May 2010 01:53:35 +0000

Here is an example of an inappropriate installation of a chimney flashing on a sloped roof that is sure to leak. When we examined the client's roof we easily spotted this inappropriate installation as the tall cone chimney flashing was installed over the shingles.

This is clearly inappropriate as water will run down the shingles and underneath the flashing. To prevent the water from entering underneath, the installer put caulking all around the flashing where it meets the shingles as you can see in the photo. It is only common sense that this is a poor installation as the caulking will eventually crack and water will run underneath the flashing as was evident by the wet stains on the boards upon stripping the flashing and shingles in the area. Further, the chimney flashing lacks a collar over the tall cone and is simply caulked.

To repair the problem we ordered a new tall cone chimney flashing for a sloped roof with collar and installed it appropriately. First we installed ice and water shield around the entire chimney area, then installed the chimney flashing and shingles over the flashing. The water will now run down the shingles onto the flashing and further from the flashing onto the shingles below. The appropriate overlap of items is installed in a common sense way consistent with the flow of water given gravity. The collar is installed and prevents an wter hitting the chimney to run down the collar and onto the shingles. The collar area is then caulked only where there is potential for the collar to leak. The tall cone is caulked only where the two parts are welded. This is an appropriate installation of a chimney flashing. If you are having a chimney like this installed be sure to consult a roofing professional as it is possible that the person installing the chimney is unaware of proper installation.

Building a slope on a small flat roof

Wed, 24 Mar 2010 21:24:20 +0000

In January we received a call from a distraught client with a severely leaking flat roof. The leakage had created significant water damage in the dining area where the flat roof was above. The entire ceiling needed to be redone.

You can clearly see from the first photo in the image gallery that the stripped deck was very wet in the one corner. We removed the plywoods and installed new insulation as the existing insulation was all wet and starting to mold.

Contributing to the leakage was the lack of slope to drain the water towards the eavestrough. To solve this problem we built a slope by installing new rafters lined up with existing rafters below the existing deck and installed new plywood over the new rafters. Essentially building a new sloped deck over the existing deck. We then proceeded to install our usual two ply modified bitumen flat roofing system with 1.5 inch poly-iso insulation. It was mid January and the sunlight hours were extremely short but our team hustled and we pulled off the entire carpentry and first base ply before dark. Our client was extremely pleased given more snow was in the forecast.

Proper drainage contributes to a longer roof life since water and snow are draining from the roof. The higher the slope the better the drainage. By building the slope with wood as above we were able to build a slope that recedes from 10 inches to zero. It is also possible to build a slope using poly-iso insulation as we often do however, the slope can recede from a maximum 3 inches to zero because 3 inch poly-iso insulation is the thickest standard available. It is more costly to build a slope from wood than poly-iso insulation but for a small roof the benefits may out weighs the costs. Given our clients experience with the water damage he decided to go ahead with rebuilding the slope from wood.