w stewart
5/28/2004
Our home has a 5V galvanized metal roof which condenses water on cold days when the sun begins to hit the metal. It goes through our living room cathedral ceiling and drips into the room. Also the flashings around the stone chimney and the ridge vent were improperly installed, and we have water stains on the upstairs ceilings. The blown insulation in the attic has been wet and is covered with leaves and other blown-in trash, creating a great environment for mold (none yet or so we think). We had an engineer inspect who said it that the installation was not the "preferred method" and should be re-done. There was no decking, felt, etc. The metal panels were directly attached to the purlins. Building codes were only recently updated in our area to mandate the use of a vapor barrier in metal roofing residential applications. However, our home's contractor has agreed to have repairs made. Here is the problem: We've been advised to have the metal removed, have the old insulation removed, new added, plywood decking with felt installed, and then the metal re-installed. But, probably to save money, the contractor wants to make repairs to the flashings, put on an approved ridge vent, and leave the current metal intact by doing the work from the inside. He has been told about a new product which is attached to the roof's rafters. He plans to have the dirty part of the insulation sucked out and new blown in through the attic and the second floor bedroom windows. Besides being very invasive (workers in and out) and probably causing insulation and dirt all over our home, we are concerned about the longevity, durability, and strength of this type of underlayment. We MUST have this done correctly this time. Our insurance will not pay for additional interior damage. Also, we could be selling in the future and this will have to pass any kind of inspection. Please advise.
Todd Miller
Classic Products, Inc.
5/29/2004
These are tough questions to answer. First of all, you need at least 1" vented airspace someplace between the insulation and the roofing. This airspace needs to have an intake (soffit vents) and an exhaust (usually ridge vent). Chances are that the manufacturer instructions for your 5V Crimp do require it to be installed over decking and underlayment. I would make sure that your roofing is installed according to those instructions. I do not know what this "new product" is that your contractor is referring to. If it is a vapor barrier, then it needs to be beneath the insulation and it needs to be completely sealed. If it is a moisture barrier, then it needs to be between the roof panels and the decking (or purlins) to which they are attached. I hope this helps.
Find a Contractor

Get Started Today

Take the first step to increasing the value of your home with a great looking, durable, fire resistant and energy efficient metal roof. Browse our list of qualified MRA Member Roofing Contractors in your area for a free consultation and estimate.