In Coquitlam the average roof is actually cedar and in most cases the house is having or just had there first re-roofing experience. Cedar is the ideal roof for new construction in Coquitlam and generally lasts about twenty years. Most in not all the roofing companies in Coquitlam are converting the cedar roof for a laminate fibreglass shingle and is some cases making a grave mistake.
The average house that was built in the eighties early nineties in the mountainous region of Coquitlam has a pretty cut up roof. Vaulted ceilings are also a big issue when you have a cedar roof converted into a shingle roof and suddenly the roof is under ventilated. What is amazing about cedar roofing today is not that it lasts long, in fact it is probably the shortest lasting product on the market today. Cedar has the ability to breath and allow the moisture to exit the home while still protecting and insulating the home. Cedar allows the home to be designed in a way they doesn't make it difficult to ventilate a two inch vapour barrier.
But in Coquitlam there is a high degree of moisture in the environment with rain coming down several times a year, the high snow loads in the hills of the City. With a laminate fiberglass shingle you lay down plywood to create a deck. The underlay is different too with today's being inorganic you get even less breathing room which covers a much larger area at any specific area compared to cedar underlay. Then the laminate shingle which is basically solidified oil.
The only way to allow the roof to breath with a fiberglass shingle the same way a cedar shake does is to install roofing vents in as many areas as possible. Over ventilating is not a problem and with vents costing about ten dollars a piece just go crazy. Ridge vents are even more useful and I recommend that everyone get the ridge vent installed if they want a absolute guarantee of a moisture free house