I don’t recommend the aluminum interlocking type of roofing because they normally want to install them over the old roofing membrane. This method does not meet with my approval. Consider a best quality GAF Fibreglass Laminated Roof installed by a certified GAF applicator. Contact one of your local GAF approved roofing companies in Edmonton. For a list of GAF Approved installers in your area, you can visit the GAF website at www.gaf.com and click on “Residential Homeowner”, then click on “Find a Contractor”, then click on the Canadian Flag, enter Alberta and you will see a list of five approved installers in Edmonton.