A-frame with cedar shake and asphalt shingles

Bill, it sounds like you're doing your research and I commend you. You have a lot of great questions. Honestly, in order to answer them, I need to ask you some questions in return. Is there any chance you could call me at 1-800-543-8938 ext 201 and we will talk all this through?

Hi, we have an A-frame cabin with cedar shakes on the steep faces and asphalt shingles on the less steep portion that provides room for the stairs to get to the loft and covers the porch. Both sections are on 2X6 tongue and grove boards, undersides of which are the ceiling inside. IE no vapor barrier, no insulation. While the cabin has a furnace it is not used in the winter. We winterize the plumbing and leave it unheated in the winter. 1. Comments on putting metal roofing [panels/sheets, not singles] over the shakes, shingles? Before I read the posts here I assumed removing the old would be required and common sense seems to indicate a level surface for the install would be preferred, but you are the experts. 2. Does anything need to go over the existing roofing before the metal is laid down? 3. Comments on exposed/hidden fasteners? 4. We have a huge circular free standing fireplace that eats up enormous space that we would like to get rid of. It has a 10" (?) insulated chimney that passes through the shake portion of the roof. Can this just be removed and the metal panels be laid over the resulting hole? 5. Reading the many posts here it seems you recommend 26 gauge panels, would that be correct? 6. Anything else we should know before we seek out a contractor? Thank you in advance for taking the time and trouble to respond to this request. Bill

1. I prefer removal of the old to properly address the substrate and make sure that you have a level and true surface to install to. The savings on removal and disposal costs are usually slight and not worth the savings (in my mind) when you figure the longevity of a metal roof. 2. Yes. You will need some sort of underlayment or slip layer between the roof deck (or old asphalt) and the new roof. Stick with the manufacturers guidelines on this. I prefer synthetic underlayment vs. traditional asphalt felts. 3. If you can afford it, hidden fastened systems are preferable because, once installed properly, the eliminate the leak potential of the fasteners. Most exposed fastener systems are fine but are commonly installed improperly and therefore leak. 4. Yes (to removal), however, I would recommend removing those surround boards from rafter to rafter and putting in new decking boards. You do not want to have a large space on the roof with no deck. The hole should be patched. 5. 26 is nice thickness of metal. We run 24 because it is only a few cents more expensive and that much thicker. 26 is a nice choice and already thicker that what a bunch of folks use. 6. Do you have any sweating or condensation issues? If so, these should be addressed in the proper insulation of the roof prior to installing the new metal system. I am sure Todd will give you all the straight scoop on everything else. He is a consummate pro and gentleman scholar.