A properly ventilated roof may last several years longer than a roof with improperly installed or insufficient ventilation. If you’re investing money in a new roof, you want that roof to last as long as possible. Roof ventilation is one area where investing a few hundred dollars in the beginning can end up saving you thousands of dollars in the long run.
Proper roof ventilation is vital in all climates, however the purpose of roof ventilation differs in hot versus cold temperatures. In Ontario, where we frequently experience both extreme hot and extreme cold temperatures, your roofing ventilation plays multiple roles, making it that much more important.
Without ventilation, the heat and humidity generated in your house by showering, laundry machines, dishwashers and other appliances accumulates in your attic. If that heat and humidity can’t escape from the attic, it can cause problems for the structure of your roof and other parts of your home.
In the winter, poor ventilation can result in ice dams forming on your roof. An ice dam forms when the heat built-up in your attic causes some of the snow on the roof to melt and then refreeze at the overhang where there’s no more heat. Ice dams form usually around the edges and they prevent water from drawing away from your roof and the walls of your home. When water backs up behind an ice dam, it finds its way under the shingles and can lead to extensive water damage inside your home. Remember this: Shingles are not waterproof. They cannot hold water. They can only shed water.
The plywood decking of your roof needs to have air circulating around it to keep it in good condition. Poor ventilation can lead to dry rot in the roof decking caused by excess humidity and or moist air. If you have to replace your roof decking in addition to your roof, this will be a significant added expense.
In the summer, having a properly ventilated attic can save you money on airconditioning costs and can even extend the life of your air-conditioning unit. This is because as we all know heat rises to the highest point in a building. Usually that’s the upper floor and attic area. Alleviating this heat in the summer can do wonders for your air conditioning cost as the air conditioner won’t have to work as hard to cool the upper floor
In rare cases of poor ventilation, the condensation that builds up in the attic can be extensive enough that it is mistaken for a leaking roof. Make sure you have your roof’s ventilation checked prior to having your roof repaired or replaced.
Poor roof ventilation can cause numerous other problems in your home, such as:
- Humidity accumulating in the insulation, both reducing its effectiveness and allowing for mold growth
- Mildew accumulating on surfaces
- Condensation leading to rusting of any metal parts in your attic or roof structure. This can lead to rusty nails bending and breaking over time, leading to further degradation of your roof’s structure.
Think of the ventilation system for your roof as an integrated and important part of your roofing system. Some care and attention in this area can extend the lifespan of your roof and pay off in the long run. Roofmaster Ottawa highly recommends upgrading to Maximum Vent Towers. These are vents which sit much higher than the old style mushroom vents and can solve many of the issues discussed above.
