Low Slope Metal Roofing

Low Slope Metal Roofing

Study Substantiates Low Life Cycle Cost: As a result of the durability and reliability of these systems, low slope metal roof manufacturers offer 20- to 40-year warranties on their products. Their long life and low maintenance requirements also put metal roofs on a very attractive life cycle cost track.This was confirmed in a 2005 study of low slope roofing conducted by Ducker International. Respondents to the study said they expected the life cycle cost of a metal roof, including outlays for maintenance, to be about 30 cents a square foot per year, far less than their expectations for built-up and single-ply roofs, at 37 cents and 57 cents, respectively.Metal roofs also have a significantly longer expected service life than either built-up roofing or single-ply roofs. Study participants said they expect metal roofs to last 40 years – 17 years longer than built-up and 20 years longer than single-ply systems.Not only can low slope metal roofing contribute to the bottom line, it can also contribute to LEED credits, which are awarded to buildings that use high recycled content and other “green” construction materials. A typical low slope metal roof has at least 25% recycled content, and at the end of its long useful life is 100% recyclable.In addition, “cool metal roofing” can significantly reduce a building’s long term energy use. With heat deflecting metal coatings, energy costs can be reduced up to 40% or more, according to a study conducted by Oak Ridge National Laboratory.
low slope metal roofing 1

Low Slope Metal Roofing

As a result of the durability and reliability of these systems, low slope metal roof manufacturers offer 20- to 40-year warranties on their products. Their long life and low maintenance requirements also put metal roofs on a very attractive life cycle cost track.This was confirmed in a 2005 study of low slope roofing conducted by Ducker International. Respondents to the study said they expected the life cycle cost of a metal roof, including outlays for maintenance, to be about 30 cents a square foot per year, far less than their expectations for built-up and single-ply roofs, at 37 cents and 57 cents, respectively.Metal roofs also have a significantly longer expected service life than either built-up roofing or single-ply roofs. Study participants said they expect metal roofs to last 40 years – 17 years longer than built-up and 20 years longer than single-ply systems.Not only can low slope metal roofing contribute to the bottom line, it can also contribute to LEED credits, which are awarded to buildings that use high recycled content and other “green” construction materials. A typical low slope metal roof has at least 25% recycled content, and at the end of its long useful life is 100% recyclable.In addition, “cool metal roofing” can significantly reduce a building’s long term energy use. With heat deflecting metal coatings, energy costs can be reduced up to 40% or more, according to a study conducted by Oak Ridge National Laboratory.
low slope metal roofing 2

Low Slope Metal Roofing

Metal Roofs Place Fewer Demands on Structure: Typically, low slope metal roof systems vary in weight from 40 to 135 pounds per 100 square feet, making them among the lightest roofing products and the easiest to install. A lightweight roofing system also places fewer demands on a building’s structural support system, an important consideration in earthquake-prone areas.Unlike non-metal systems which require an underlying substrate or deck, low slope metal roofs can be applied directly over bar joists or purlins. And, because of their interlocking or active fastening systems, metal roof panels are designed to meet the requirements of ASTM E1592, UL 580, UL1897 and other severe wind and uplift tests.Metal roofing products come in a variety of materials as well as many colors, textures and profiles. To ensure longer life, almost all low slope roof materials are protected from the elements by high performance, highly durable metallic coatings.While the idea of protecting a building with metal originated centuries ago, the concept is still valid today. Whether the goal is many years of low-cost, low maintenance, problem-free performance, or an environmentally responsible approach to roofing, low slope metal roofs make sense.
low slope metal roofing 3

Low Slope Metal Roofing

Typically, low slope metal roof systems vary in weight from 40 to 135 pounds per 100 square feet, making them among the lightest roofing products and the easiest to install. A lightweight roofing system also places fewer demands on a building’s structural support system, an important consideration in earthquake-prone areas.Unlike non-metal systems which require an underlying substrate or deck, low slope metal roofs can be applied directly over bar joists or purlins. And, because of their interlocking or active fastening systems, metal roof panels are designed to meet the requirements of ASTM E1592, UL 580, UL1897 and other severe wind and uplift tests.Metal roofing products come in a variety of materials as well as many colors, textures and profiles. To ensure longer life, almost all low slope roof materials are protected from the elements by high performance, highly durable metallic coatings.While the idea of protecting a building with metal originated centuries ago, the concept is still valid today. Whether the goal is many years of low-cost, low maintenance, problem-free performance, or an environmentally responsible approach to roofing, low slope metal roofs make sense.
low slope metal roofing 4

Low Slope Metal Roofing

. . . is that you can to find the best configuration to suit the local environment and built to last. However, in older Eichler’s and similarly designed homes from the 50s, like the one I own near San Francisco, a roof retrofit can be a monumental challenge. I have interviewed a large number of roofing contractors and to date I’m not convinced that any one of them have a firm grip on the best approach to re-roofing with design considerations to satisfy insulation requirements, which would include mold prevention down the road. my roof has a 2.1/2 in 12 pitch, the gentle slope does not qualify for conventional roofing materials and my options are limited to sheet-metal, torch down, or self adhering membranes, FINE! The problem is the overall depth from 1×6 D.fir T&G planks, to the top of the sheet metal is limited by what would be practical to assemble and secure over the top of these planks. Planks which are nailed across 3×5 rafters, spaced 30″ o.c. and tied at the ridge, sitting on outer loadbearing walls, all this beautiful old growth Doug fir exposed to the living area. The easy way out would be to have a closed cell foam contractor spray the entire bottom side of all the rafters and 1×6 planks, and finishe this ceiling with dry wall. That would satisfy both vapor barrier, insulation, and simplify the re-roofing project, at the expense of destroying all the charm & character of this 50’s architecture. I would did used to it but still with hate myself for covering up all that beautiful quarter sawn old-growth Doug-fir. My next option is to peel off everything that’s the above the planks now, R&R any dry rot, then focus on implementing a solution on the exterior and leave the inside wood ceiling intact. 1. cover the entire roof deck with 10mil poly ethylene, then 2. Stack two layers of 2″ Polyso foil-backed rigid sheets of foam, staggered and taped at the seams, secured to the rafters with 5 inch screws. 3. then a layer of Tyvek-roofing membrane or self adhering GRACE, or GAF against water penetration. 4. Then 2×2 or 2×4 straps screwed down, which will accommodate sheet-metal snaplock brackets, 5. Lastly finish off with 16″ panels of steel roofing. (Alternatively, a layer of 1/2-inch OSB atop the wood straps, covered with adequate underlayment, and topped off with roles of self adhering or torch down roofing).
low slope metal roofing 5

Low Slope Metal Roofing

15. Apr 29, 2014 1:59 PM ET advantage of new construction versus retrofits by Farrokh Khodadadi . . . is that you can to find the best configuration to suit the local environment and built to last. However, in older Eichler’s and similarly designed homes from the 50s, like the one I own near San Francisco, a roof retrofit can be a monumental challenge. I have interviewed a large number of roofing contractors and to date I’m not convinced that any one of them have a firm grip on the best approach to re-roofing with design considerations to satisfy insulation requirements, which would include mold prevention down the road. my roof has a 2.1/2 in 12 pitch, the gentle slope does not qualify for conventional roofing materials and my options are limited to sheet-metal, torch down, or self adhering membranes, FINE! The problem is the overall depth from 1×6 D.fir T&G planks, to the top of the sheet metal is limited by what would be practical to assemble and secure over the top of these planks. Planks which are nailed across 3×5 rafters, spaced 30″ o.c. and tied at the ridge, sitting on outer loadbearing walls, all this beautiful old growth Doug fir exposed to the living area. The easy way out would be to have a closed cell foam contractor spray the entire bottom side of all the rafters and 1×6 planks, and finishe this ceiling with dry wall. That would satisfy both vapor barrier, insulation, and simplify the re-roofing project, at the expense of destroying all the charm & character of this 50’s architecture. I would did used to it but still with hate myself for covering up all that beautiful quarter sawn old-growth Doug-fir. My next option is to peel off everything that’s the above the planks now, R&R any dry rot, then focus on implementing a solution on the exterior and leave the inside wood ceiling intact. 1. cover the entire roof deck with 10mil poly ethylene, then 2. Stack two layers of 2″ Polyso foil-backed rigid sheets of foam, staggered and taped at the seams, secured to the rafters with 5 inch screws. 3. then a layer of Tyvek-roofing membrane or self adhering GRACE, or GAF against water penetration. 4. Then 2×2 or 2×4 straps screwed down, which will accommodate sheet-metal snaplock brackets, 5. Lastly finish off with 16″ panels of steel roofing. (Alternatively, a layer of 1/2-inch OSB atop the wood straps, covered with adequate underlayment, and topped off with roles of self adhering or torch down roofing). Seems like a good plan, but the need for adding adequate cavity for venting the roof further complicates this scenario. Additionally, many articles on the subject warn against using more than one layer of vapor barrier. So that polyethylene-based layer, covered with impervious sheets of Polyso, topped off with water barrier underlayment has been flagged by some writers as inadvisable approach. So in the long run I don’t really know what is the best way to re-roof, I only know that by doing get myself I have as good a chance of getting it right as paying a so-called professional roofer too screwed up for me for thousands of dollars more, has he is faced with the same see of conflicting information, has construction methodology and building science appear to be riding along separate parallel paths that are yet to converge. Sincerely, -F-