Yes and no. Yes in that different roofing materials require different methodologies which can impact the systems installation costs. Never allow inexperienced contractors to penetrate a flat roof, only experienced professionals should ever work with these difficult roofs. If your roof will need to be replaced during the next ten years we recommend that you replace it before having your systems installed. Some roofs are more costly to install on than others – flat, tile, and wood shake are more difficult whereas standing seam metal and composite shingle are easier. Many installers, including Sunergy, will not install on wood shake or tile roofs that do not have a solid decking underneath, otherwise called spaced sheathing or skipped decking.