You are here:

Roofing/Low slope roof options



I have a low slope roof on my house that currently has a 14 year old tar and gravel roof that leaked into my bathroom during a rainstorm. I live in Montreal, Canada where we have extremely cold winters and short hot summers and was an wondering what is the best option for re-roofing. I was given a choice of elastomeric membrane or TPO but had heard TPO could increase my heating costs (currently $650 month to keep the house at 60 degrees) not something I want to do. Also the roofer quoted me $11,000 which I thought was an outrageous price for a 1200 square foot roof. There is no attic (cathedral ceilings) and wondered if I also need vented soffits as I always have an ice dam on one edge of the roof and huge icicles in the winter. Any information would be appreciated. Thank you.

I don't see how the roof membrane can impact the heating bill significantly enough to factor it in. Insulation is far more of a factor. I never worked with TPO, It does not have a long track record. $11,000 is ridiculous for a 1200 sq ft roof. You cannot get rid of ice damming. It's a factor of roofs. I guess you could get rid of it if you remove all your insulation int he attic but I don't think you want to do that. Roofs are warmer at the top so the top melts first and then the water runs down and refreezes at the bottom. It's just how a roof works. If you get a really warm day it might melt the entire roof at once. You could put a heat wire in the gutter to keep water flowing.



All Answers

Answers by Expert:

Ask Experts


Brad Zacharia


All aspects of residential Roofing. This includes shingles and flat (low slope) roofs. I have knowledge in the installation as well as the design of roofs from an engineering standpoint.


I have been doing roofing for 40 years. This was my father's business and I took it over in 1980.

I have written responses to artcles that I felt needed a response to and those responses have been published in roofing trade magazines.

BSEE Drexel University

©2017 All rights reserved.