We need a new roof for a somewhat unusual house, and we are considering an unusual design. I would appreciate opinions. THE PLAN (steeply pitched roof, all work done from outside): 1.) Remove the existing three layers of asphalt shingles. 2.) Replace any rotten decking with plywood. 3.) Synthetic underlayment over all decking. 4.) Add two layers of 1.5-inch rigid foam (closed-cell, polyiso core integrally laminated to heavy black, non-asphaltic, fiber-reinforced felt facers), staggering all seams so that they don’t line up. Here’s the link on the supplier’s website to the exact product, at 1.5 inches thick: http://www.alliedbuilding.com/products/productDetail.aspx?ProductID=12221110 Here’s the link on the manufacturer’s website to this same material (at various thicknesses): http://www.atlasroofing.com/tabbed.php?section_url=16 5.) Englert’s 1500 series 0.32 aluminum standing seam metal roofing. Link: http://www.englertinc.com/roofing-panels.aspx?Page=6 GOAL: To put on a roof that will last a long time, since we have money now from a refinancing (for various repairs), but are unlikely to be able to refinance in the future (we are probably hunkering down into retirement soon). BACKGROUND: The house is on Staten Island, NY (about 3 miles from the water, and up on a hill). It is a Cape Cod-style, brick exterior house from the 1940’s with a steeply pitched, 1600 square foot roof (two valleys), with three layers of asphalt shingles over 5/8-inch tongue and groove decking. There are no soffits, so there is no soffit venting. There is no ridge vent. We have leaks at flashings (around two chimneys and a skylight), and on one slope of the roof some shingles have come off – the decking is visibly uneven in about a 30 square foot area there. It is unclear whether this area got this way because branches from a tree (we have since taken the tree down) were rubbing against the roof, or because this area is below a chimney that has flashing leaks, or both. There are two bedrooms, a small storage room, and a half-bath upstairs, under a cathedral ceiling. The rafters are 2×6’s, 18 inches on center. About 10 years ago, most areas upstairs had old and crumbling wallboard. This was taken down and replaced by sheetrock, after the installation of fiberglass batt insulation in the rafter bays. (I was told that the depth of the rafter bays is really 5-1/2 inches and so the insulation, meant for a 6-inch space, is crammed in tightly.) There are no baffles for the insulation. There are kneewalls with access doors. The insulation in the area behind the kneewalls follows the slope of the roof (rather than following the kneewall and floor). In one small area (over the stairwell and landing), nothing was done ten years ago (other than to paint), since that area had the original plaster rather than the crumbling wallboard. So I don’t know what kind of insulation, if any, is in that small area. There is falling paint and a bit of mold in the stairwell where the sloping ceiling and two walls meet (which may indicate that there is no insulation there and warm moist air rising from the kitchen hits cold surfaces – or it may simply line up with the area of missing shingles – I’m not sure). The upstairs is extremely hot in summer and we have to use A.C., but in winter we don’t even turn on the baseboard heaters upstairs because the warm air rising from downstairs (radiators – we use fuel oil) is enough. What do you think of the tentative design for the new roof? (To clarify: we would not be adding any venting or air space, and we would not be taking out the old insulation.) Thanks, Elsa