Many home owners don’t think about it so much until problems arise. It’s one of your biggest assets’ biggest asset; your roof. The roof on a home is the most important first line of defence to keep the elements out of your home. It helps keep moisture out and pests outside. A good roof design helps redirect rain water to the eaves which carry water away from the building. So what happens when your roof gets old, tired, and begins to fail? A lot can happen and many home owners don’t notice until costly repairs are in order to rectify the problem and repair the damage.
Recently we had the roof redone on our century old home as part of a significant renovation. The reason was partially for preventative maintenance but also because we suspected something was going on based on the outward appearance. Our home consists of a high peaked roof at the front of the home with a flat, slightly sloped roof at the rear. To the untrained eye it didn’t look too bad. Yes there were a few dips on the peak and the flat roof did have a small puddle on it (Could see it from a neighbours roof-top deck) but all in all, from a distance it looked fine. No missing or curling shingles, no cracks, and of course no water pouring through the ceiling inside. It’s a good thing we had it replaced. Like a Monet, good from afar but very different up close.
In order to fully understand what we found and repaired here is a basic lesson on roof anatomy. A roof consists of 3 components along with minor components to supplement the major ones. The major ones are rafters, decking or sheathing, and shingles. Moving from the inside out, the rafters support the decking, the decking supports the shingles, and the shingles protect everything underneath from moisture and the elements. The more minor components are underlayment, fascia, soffit, vents, flashing, and drip edge. The underlayment is a layer of material, usually tar paper or a synthetic substance, which is placed on top of the decking before shingles are installed to offer an additional layer of protection from moisture. Fascia is trim used to cover the end of rafters and to which eaves troughs are normally attached. Soffit is the finished underside of the eaves between the end of the rafters and the exterior wall of the house. Vents are located higher up on the roof to do just what their name says; vent air from the attic and allow fresh air in to keep air circulating. Flashing is pieces of metal (normally aluminum) used to prevent moisture penetration around any intersections or projections in the roof such as vents, chimneys, and valleys. The drip edge is edging (normally galvanized steel or aluminum) that is placed at the end of the roof along the eaves which allows water to run off and drip clear of the sheathing, rafters and underlayment.
Upon closer inspection of our roof it was determined that there were 3 layers of asphalt shingles on the front of the peaked roof and 2 layers of asphalt shingles covering the original cedar shakes on the rear of the peaked roof. On the flat roof there were at least 3 layers of membrane, tar, tar paper, and gravel along with a bad repair job , a significant crack in the membrane, and of all things, a sapling growing in the gravel on it. Since the rule of thumb is no more than 3 layers of shingles on a roof we were advised that the roof would need to be stripped down to the sheathing. I am very glad we decided to do this. Once the stripping was complete our roof told a distinct story. A wasp nest in the flat roof soffits, a bad repair job to front of the peaked roof, an abandoned squirrel’s nest in the soffits of the peaked roof, and sheathing that had absolutely no support around where the electrical service connected to our home. That would explain the dip that seemed to increase in size year by year.
Although these repairs were considered to be minor they had the potential to be costly repairs. The crack in the membrane on the flat roof would only have gotten worse and it was only a matter of time before water permeated the attic. A wasp nest has obvious problems associated with it. The bad repair job on the peaked roof was done poorly and the shingles in the area were starting to curl slightly. Not to mention the wood sheathing in the area had not been repaired but only covered with a sheet of vinyl then shingled over. A squirrel’s nest in your attic or soffits is not a good thing. Squirrels are quite destructive and can chew through wiring creating a fire hazard. Also the potential for disease from feces, urine, fleas and tics is quite real. The most surprising element of the repair was the lack of support under the sheathing around the electrical service entering the house. The roofers said it was only a matter of time before this section of the roof caved in which would create a huge headache for us not to mention a costly repair job.
Water permeation of your roof can lead to a series of other problems such as mould, dry rot, structural deficiency, insect infestation (termites and carpenter ants in particular), electrical issues, insulation issues, unsightly water stains on your interior walls and ceilings, and the risk of the interior ceiling caving in. Looking after the roof on your home is paramount and saves money in the long run. For more information on roofing go to the Canada Mortgage and Housing Corporations website article on roof repair .