If you only have one layer of roofing, you do not necessarily have to tear off the entire roof in order to add metal shingles. Another option is to place a layer of metal roofing over the existing layer. This is an easier task and is allowed by building codes in most cases. There are a few municipalities that require that the roof be torn off, but most will allow one additional layer.
The Underlayment Method
The simplest solution is to add a new underlayment over the already existing roof. Then, the new metal roof is installed over this underlayment. The type of underlayment you choose is critical if you select this option. The building enclosure will need a water barrier, vapor retarder, thermal insulation barrier, and an air barrier. The right roof underlayment needs to be selected based on the roof slope, the metal roofing system, the ambient conditions and the geometry. If you are unsure about which type of underlayment you need, consult with a metal roof installation contractor.
The Purlin Or Batten Method
Another way to install a metal roof is to use purlins or battens. These provide the installer with a flat surface upon which the metal roof panels can be laid down. This system overall is stronger than simply screwing a frame to the rafters. The best way to install a steel roof over asphalt is to go with the steel shingle system. The shingles are installed in horizontal rows in a manner similar to other types of shingles. The best shingle systems are installed on a frame of 2x2s. The frame is screwed to the rafters and the shingles are screwed onto the frame. This allows for the roof to withstand high winds. Another great thing about the frame is that it creates a ventilation gap that keeps ice dams from forming in the winter and keeps the home cool in the summer.
When You Can't Install A Metal Roof Over An Existing One
If you would like a new metal roof, but your roof already has two layers, it will be necessary to tear the existing roof off in order to put another roof in place. Always call your local building department to verify whether you are allowed to add an additional layer to your roof. Some areas have restrictions about how many layers of roofing can be in place at any one time.Share
20 June 2017
My sweet spouse and I are building a new master bedroom onto our small home. I’m so excited about this fun, renovation project. I’ve already started shopping for beautiful furniture to fill this bedroom with. Are you currently searching for the perfect pieces of furniture to put in a new bedroom? If your bedroom contains a large closet, you might not need to buy a dresser. Instead, you may want to invest in a large bed complete with a decorative headboard and a footboard. You may also wish to look for a gorgeous chaise lounge to relax in while you read books at nighttime. On this blog, I hope you will discover valuable tips to help you buy pieces of furniture you’ll cherish for many years to come. Enjoy!