You never know what you are going to find when challenged with finding and stopping a leak. Today’s charge was a tricky one. It leaked through a ceiling fixture in a library room of one of the Shaughnessy mansions in Vancouver. I never considered it to be a roof leak as the roof above the library was solid. Yes it was tar and gravel, which is difficult to assess integrity on, but the T&G roof appeared qualitative enough. We focused our attention on an abutting eaves trough. A thorough dis-assembly of a suspect detail resulted in the finding of the culprit. If we weren’t thorough and just guessed at what it might have been, we wouldn’t have found it and satisfactorily serviced the home owner. What we found was all hidden behind fascia boards and exterior crown moldings so it was not right in front of our eyes. We discovered that the aluminum eaves trough was placed directly on top of an internally plumbed ABS plastic drain pipe. The butt junction between the aluminum and ABS was sealed with a roofers mastic (which had dried and cracked). This became obvious after we removed a small brown plastic strainer that was inserted into the eaves trough hole. This brown plastic strainer had a stem which projected 2” down into the ABS plumbing. Therefore this strainer could essentially bypass this weak aluminum/plastic junction. HOWEVER, this strainer was no longer sealed properly to the aluminum eaves trough so water was getting underneath the strainer and then entering through the weak aluminum/plastic junction and flowing into the house. Now who would have thought of that as a remote possibility when first arriving on site to a roof leak? It wasn’t my first or twenty-first possibility! Leak finding is not an exact science. It takes logic, common sense and a little bit of luck combined with an attitude of never quitting. A challenge solved, such as this, is worth bragging about. Mission accomplished.
Vancouver torch-on roofingTorch on roofing is similar to tar and gravel, consisting of layers of flexible fibreglass and polyester with bitumen. But unlike tar and gravel, it is applied with a torch instead of a hot mop. You don’t experience the unpleasant odours associated with tar and gravel. Sheets are torched down during installation, using large torches that melt the asphalt at the seems, joining them permanently together. The final result is the vulcanization of a large rubber sheet to a flexible fibreglass base. The process is often referred to as modified bitumen because asphalt is mixed with rubber compounds. Torch down roofing provides added strength and resistance to flat and low sloped roofs. It has an average life expectancy of 20+ years.
Torch on roofing is generally considered a more attractive roof than tar and gravel. Its flexibility makes it a good choice for the climate change and extreme weather conditions of the West Coast. It can shift as required and resists brittleness. Torch on provides excellent waterproofing and it is a fire, wind and hail rated roofing system.
Self adhering modified bitumen sheets are available, making patch repairs both practical and cost effective.