Displaying items by tag: roof leak

Leaking door step from walkout to flat roof

2010-05-17T02:39:46Z

Some downtown Toronto homes feature a rear sloped roof with a dormer with a walkout onto a flat roof. Very often we encounter that the door step has not been appropriately sealed and flashed and is therefore leaking, as was the case with out client’s home in the the downtown Toronto Annex neighbourhood.

Upon stripping the existing flashing we encountered the usual case, the rubber membrane did not extend up onto the door step. The door step was simply covered with metal flashing which will not seal the door step from leaking, it serves an entirely different purpose. It is the rubber membrane the serves the purpose of sealing the roof. The purpose of the metal flashing is to protect the rubber cap on the door step. The rubber cap is a membrane which features ceramic mineral granules on its surface to protect the membrane from UV exposure and thus material deterioration. When the client walks on the door step, the granules will eventually loosen and lead to premature deterioration in the material. A metal flashing is installed to prevent this. Another reason for the door step rotting is condensation from the lack of rubber membrane on the door step. As you can see from the image above the door step was clearly leaking and rotting.

To repair the problem we removed the rotten wood in the door step and rebuilt a new door step. We then ran the rubber base membrane over the rebuilt step extending the rubber as far as possible towards the door. Subsequently, we installed the rubber cap membrane over the base running it as far as we could under the door. Ideally, if possible the door should be removed, the membrane extended under the door and then the door should be re-installed over the membrane. In this circumstance it was sufficient enough to run the rubber cap under the door step and lower the cost to our client. We then installed a metal flashing that extended a few inches under the door to protect the membrane on the door step. Finally, we caulked the area where the door step and door meet. The metal flashing serves the other purpose of allowing the caulking to have a solid surface to me applied to. The caulking now rests against the metal flashing on the door step and the door. If the flashing was not installed and caulking applied onto the rubber cap the granules on the cap would eventually loosen as discussed and so would the caulking, eventually leading to leakage.

To finish the project aesthetically we covered all the existing wooden frames and fascia which featured wood with peeling white paint with black aluminum flashing. We also installed new a new eavesthrough and downspout. The charcoal cap on the flat roof, black laminated asphalt shingles and black aluminum flashing match nicely for a clean look.

Leaking chimney flashing

2010-05-11T01:53:35Z

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

2010-03-24T21:24:20Z

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.