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What are my options in roofing material for a porch roof with a 2:12 pitch. Looked into standing seam aluminum and galv. steel- too expensive. A cheaper alternative is to use dimensional shingles, but am concerned with this low pitch ( I live in NE Ohio). Can I use dimensional shingles over Ice-guard applied over the whole roof? Or is roll roofing my only economically favorable option? I am concerned with aesthetics as well as durability.
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In 1996 I added a 640ft^2 addition (14x44 +/-) to a home in Rochester NY using a 2/12 roof. I choose a mop down rolled roofing material. There is an under layment that is nailed down first to the sheathing with large head nails. The top layer is a very heavy rubber type material made by either Firestone or Goodyear. It has a surface similar to regular shingles and the roles are 100’ by 39”, with a coverage area of 360 ft^2. The top layer is “glued” down with mastic specified by the manufacturer. The whole process went very smoothly and to date, I have not been called back. I talked to one of our local roofing suppliers about the situation and was directed toward this product. I have no regrets and the customer is happy. If you want additional information, let me know and I will get more specific.
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I have covered such a pitch (shed dormer) with CertainTeed WinterGuard under standard asphalt shingles. The shingles were essentially for show in this application so as to blend with the rest of the house's roof. The WinterGuard has worked fine to keep any stray water where it belongs. House is in western Wisconsin.
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Me too....never had a problem
*I also have a low-pitched porch roof (in a snow area) where I wanted to use standing-seam metal for aesthetics since the surface is very visible from bedrooms on three sides of the house, but was advised the slope is not great enough. I wonder if the CertainTeed WinterGuard product would work under the metal... Any suggestions would be appreciated.
*Low slope asphalt shingles are available, they are wider ( as in the distance up the pitch) than standard shingles and have to be individually tarred down, no handy little tar stripe supplied, but the deeper overlap, reduced exposure, and applied tar make them very weatherproof. Standing seam steel is not recommended for slopes less than 6/12, and I'm sure every screw/nail hole passing through the Winterguard would be a potential leak. . . 'course you could always try gluing the steel down with contact cement (chortle,chortle).
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Jim,
Another possibility to consider is a cold-process built up roof (BUR). It works well on very low slopes. In fact, I don't know if 2 in 12 might even be too steep since I have never put it on anything steeper than about a quarter inch per foot. I spent more time applying cold BUR than I would like to remember, in some pretty harsh conditions (Phoenix), and the process worked well. It isn't very expensive, has none of the disagreeable features of hot BUR, and has an excellent lifespan for the cost if you apply a reflective coating, which I would strongly recommend. One of the premier BUR material manufacturers is there in Ohio. The company is Tremco, you can find their phone number at tremcoroofing.com. I suppose a tech rep would be glad to say if their material was appropriate for your intended application.
I hope we can get some more responses on this -- improper roofing result in problems for everyone, and I am always interested in hearing about better methods, materials, and techniques.
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Jim,I am from Akron and I have had this situation many times.About 90% of the time I install a seamless rubber roof over a smooth underlayment.I buy this material by the full roll because I use a lot of it each year,but my supplier also sellssmaller pieces at a slightly higher price.this glues down with a contact-type adhesive and if you do it carefully it is simple and very neat.My next choice would be 90# roll roofing over icegaurd or weather watch.Both of these ways work best in a lot warmer weather than Akron has today.If you want more details please ask. Good Luck , Stephen.
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After you go through all that extra labor, you might as well have gone with a metal roof. My "Klip-Rib" roof by BHP is fantastic. Looks great and went down so fast you couldn't compete. It's anchored with clips which are screwed down to rafters or sheathing. The leading edge of the sheet gets a clip screwed down over it and the next sheet snaps over the clip. The roofing will support a person walking on ridges or pans with clips installed at only 5 foot intervals. I've used the product for my studio/shop and for a hay barn, both without sheathing.
*David,Where do we find this Klip-rib? It sounds great.Dave
*BHP stands for Broken Hill Proprietary, an Australian company with manufacturers and distributors in the US. I bought my Klip-Rib roofing from Rocky Mountain Wholesale Supply in Alameda, California, talk to Rose 1-800-339-9262. There's a manufacturer in Sacramento, CA where you can get details and specs, talk to Leslie 1-800-272-7023.Sorry if this sounds like I work for BHP. I don't...just happy with their product.David
*Jim - Try the Soprema website. They make a membrane roofing material called "elastophene." They sell it both as an underlayment and as a glue down granular surface sheet. I believe this is the system Ken referred to (Ken - did you buy it at Allied?) It looks like regular roll roofing, but is an elastomeric membrane so it lasts much longer.I think the problem with metal on a low slope is that the water resistance is limited by the height of the rib. Where a shingle roof could leak with a 1/4" of ice damning a shingle roof won't leak until water backs up higher than a rib - even with the concelaed fastener and clip systems like David talked about. Metal Sales makes a similar product. A membrane type roof should never leak.David - what does the BHP system go for. I am told the metal sales system (non structural - needs sheathing) will be about $1.20 psf for 24 ga kynar equivalent paint (materials only - I install)-Rob
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David Giuliani,I won't be laying awake at night worrying about my seamless rubber roofs competing with Klip-Rib for the following reasons.1.
the ability to install a roof up to 20'x50' with zero seams compares very well to a roof with a seam every few inches (or even every few feet) 2.I would not be worried about my roof blowing of since it can be fully adhered instead of just screwed down every 5 ft. 3. my material would be locally available for Jim T. and has proven itself many times in the local climate instead of Klip Rib which apparently would need to be special ordered and shipped cross country from Califonia. 4. Speed of installation is not a factor when installed by a professional or even when installed by a reasonably capable homeowner. 5. Please refer back to reason 1. snow and ice on a seamless roof in Jim T's locale (N.E. Ohio) vs. snow and ice on a flat roof with many potential leak causing seams. The January '98 issue of fine homebuilding had an excellent article on this material and the actual installation on most roofs would be much simpler than the one shown in the article.By the way, I am sure that Klip Rib would be an excellent material in your climate but where Jim and I live I would hesitate to install it.
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Steven - what does your rubber roof look like? Aesthetic options? I'm picturing tarmac, please enlighten me.
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Andrew , the material I use is flat black in color although I under stand it is also available in white. since this material is for flat or low slope roofs it is not visible from the ground.If you use good workmanship appearance will not be an issue.Most of my customers live in 50-80 year old homes that have had leaky 90# roll roofing or built up tar roofs on their flat roofs. They are used to black flat roofs and would not care if the roof was hot pink if it does not leak.good luck Stephen. ps. This material sells very well in the more upscale areas where we are doing business. If these customers will buy it I am sure most customers will. at $35-55 a square the material costs for the rubber compete very well against your other choices, most of the roofs we use this for are about 10x12or16x22
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What are my options in roofing material for a porch roof with a 2:12 pitch. Looked into standing seam aluminum and galv. steel- too expensive. A cheaper alternative is to use dimensional shingles, but am concerned with this low pitch ( I live in NE Ohio). Can I use dimensional shingles over Ice-guard applied over the whole roof? Or is roll roofing my only economically favorable option? I am concerned with aesthetics as well as durability.