Reg Evans Posted January 30, 2009 Report Posted January 30, 2009 Actually....The shingles are only protecting the felt paper underlayment which is the real barrier against water dripping on your head. According to the code here in No. Calif. any roof under a 3 and 12 pitch requires 2 layers of 15# felt. I don't know what the code calls for with a pitch less than 1.5 and 12. The pitch on Arthurs cottage appears to be maybe 1 and 12 and I'm willing to bet it's not gonna leak.....ever. Quote
eric wissing Posted January 30, 2009 Report Posted January 30, 2009 The roof should be great. Norm, I believe is thinking about ice damning. I bet the snow on Arthurs roof wasn't there more than an hour or two. The house I am planning here might just have a flat roof. With the new membrane roofing leaks should be a problem. Eric Quote
Plymouthy Adams Posted January 31, 2009 Report Posted January 31, 2009 Reg...the roof will be removed and full use of the attic space is planned..the reason for this approach is the unpredictable weather we are having..have sent you a better overview.. Quote
Norm's Coupe Posted January 31, 2009 Report Posted January 31, 2009 Well guys, as the old saying goes. Do what you want on a roof or anything else. Actually, I wasn't referring to any code from any state or local authority. I was referring to what about 99% of roofers would tell you about a roof with that small of a pitch. It may pass code with shingles, but you'd probably be hard pressed to have a contractor or a roofing supplier recommend shingles on that type of pitch. That's regardless if it's going to have snow sitting on it. They would usually recommend either a built up roof using 2 layers of 15 lb. felt crisscrossed, and two layers of 50 lb. felt on top of that, then the top coating. Also an adhesive coat on the deck and between each layer of felt. Then flashed in around all four edges. Or a rubber membrane roof system. Quote
Arthur1947 Posted January 31, 2009 Author Report Posted January 31, 2009 Contrary to popular belief, roofing felt is meant to draw moisture and dissipate it from the roof sheathing, to prevent mold growth. A heavier rated felt is just another way a contractor can up the cost of a job. In this case thicker doesn't mean better. Best. ARTHUR Quote
Norm's Coupe Posted January 31, 2009 Report Posted January 31, 2009 Contrary to popular belief, roofing felt is meant to draw moisture and dissipate it from the roof sheathing, to prevent mold growth. A heavier rated felt is just another way a contractor can up the cost of a job. In this case thicker doesn't mean better.Best. ARTHUR That's not true about drawing moisture. Roofing felt is asphalt impregnated to repel water, not absorb it. Then when the roof is slightly pitched such as yours, a good asphalt coating is put on top of the top layer of felt. That protects the felt from drying out and cracking. Using the four ply system I mentioned and keeping the top coat in good shape by recoating every 6 to 10 years minimum, it should last almost forever barring any damage from a bad storm, etc. The four ply system isn't simply to raise the cost. It's just the best way to go. You can go with a two layer system using 1 layer of each weight felt, or the three layer system using 2 15's and 1 50 lb. layer too. The purpose of the layers is strength against expansion and contraction of the roof. If the roof coating is kept up as mentioned, the felt doesn't dry out and each layer expands and contracts in different directions, cutting down on splitting of the felt and top surface when it does expand and contract. Like I mentioned, I've inspected countless built up roofs over the years. On the ones that were just half way kept up, the adhesive between the layers and all layers of felt were still nice and pliable. The adhesive was still sticky too, even after 30 years or more. The key is that you have to keep the top coating nice and pliable. Being in a hot climate it's also better to use an aluminum coating as the top coat to reflect the sun and heat. That will reduce the top roof temperature about 15 to 20 degrees, making it cooler in the building and the roof coating last longer. That said, if you have shingles on a roof for 20 or 30 years they dry out a lot. Some cheaper shingles don't even last that long. Then when you walk on the roof for some reason you'll find it sounds like you are walking on egg shells because they are so brittle. When they get like that, they are far from being a waterproof covering. Moisture will go right through them then, get between the shingle and the felt, then start to deteriorate the felt under it. Then slowly soak through the felt, then start to rot out the roof deck. I'm not into roofing anymore. Can't climb ladder's that well anymore due to the arthritis in my knees. So I have nothing to gain. Just passing on the information based on many years of experience for what it's worth. Quote
Plymouthy Adams Posted January 31, 2009 Report Posted January 31, 2009 On a roof that flat I would look to metal or roll roofing..metal being my first choice...if there is any chance of freezing..that low a pitch will hold moisture and seep back and will expand and lift and well..you know the rest of the story...climate is everything.. Quote
greg g Posted January 31, 2009 Report Posted January 31, 2009 I just put metal roof on a lean to portion of a barn. the original roof 15 pound felt, and rolled roofing lasted nearly 30 years. Hopefully the metal will last at least 30 and then I won't need to worry about it again. Quote
Norm's Coupe Posted January 31, 2009 Report Posted January 31, 2009 Actually, the rolled roofing system Tim & Greg mentioned would be okay too. You may have to replace the rolled roofing after it's dried out, but it will be better protection than shingles. Don't think I would use the metal roof on a building someone is going to sleep in. If you've ever been in a building with a metal roof, they can make a lot of noise in the rain. I'm talking a building with a 20 to 30 foot ceiling and well insulated on the inside and you still get the racket when everything else is quiet inside. A low ceiling like Arthur's would be much louder. Quote
Frank Elder Posted January 31, 2009 Report Posted January 31, 2009 Metal roof, hail no! Rain, put you to sleep like a baby....14 years sleepin' under one in the hill country, New Braunfels, TX. Quote
Plymouthy Adams Posted January 31, 2009 Report Posted January 31, 2009 you right on that Frankie...metal roofs and rain..lullaby music.... Metal roofing is the up and going thing here in the south with older houses and such..sure makes them look like yester-year items.. Quote
Norm's Coupe Posted January 31, 2009 Report Posted January 31, 2009 When I was talking about the noise I was thinking of his daughter who had to sleep in the building. Actually, if it's dead quiet in a building with a metal roof and it's expanding or contracting with the heat and cold, it could be a little creepy to a younger person. That roof will pop and creak as it's expanding and contracting. There are other problems associated with metal roofs too. That's the seams and mechanical anchors such as the bolts or nails used to hold it onto the building. Nails are bad because they will pop out faster with the expansion and contraction of the building, causing a leak around the nail hole or loose nail. If bolts are used, they usually have a rubber gasket under them to seal against water. Those dry out in about 8 to 10 years and start to leak around the bolt hole's. Some of the screws will also start to back out at that time from expansion and contraction. The seams between the metal sheets are also usually sealed by a caulk or rubber seal, sometimes even interlocked with a seal. Again though, those seals do dry out in about the same amount of time and start to leak. You may not notice it as much inside the building until it becomes really bad, because the water will usually follow the pitch on the metal roof and roll out the edge, outside the building. That all depends on the pitch of the roof too. When trying to repair those leaks it can be a nightmare. Since it could be coming from any one of those problems mentioned above the following is usually recommended. 1) Remove all the bolt and replace all the rubber seals around them. And there are usually a lot of those bolts and it's time consuming. 2) Either caulk or apply a small amount of roofing cement to each bolt. 3) Reseal the seams by applying a heavy coat of roof coating over each seam, then roll out either fiberglass membrane or polyester membrane over the wet coating, then apply another good coat of roof coating over that for each seam. Of course, not the roof doesn't look so good, so usually you'll want to coat the whole metal roof to make it match. Metal roofs actually became popular back in the 60's for industrial plants. Whole industrial parks had metal roofs on them because they were cheaper to build. The buildings were even metal buildings. The most popular in the 60's & 70's were Butler Buildings. At first we thought those would hurt the roof coating business. But.........after about 10 years of being built, our business boomed because of them. So.........before replacing your old shingles, etc. on a house, I'd check with the owners of the older metal industrial buildings if I were you guys. There is no such thing as a roof that will last forever, or one that requires no maintenance. Also keep in mind, you don't really want to go cheap on a roof. A roof is probably one of the most important parts of the building. If it starts to leak, the roof is not only damaged, but so is the building, and it's contents inside the building. Quote
Plymouthy Adams Posted February 11, 2009 Report Posted February 11, 2009 (edited) it will still be a bit before I get back out in the shop turning wrenches and burning a bit of weld rod, slapping bondo or spraying paint...however..the dormers are painted..the front one was a trip to paint..wife kept me anchored from the other side with a rope tied to my safety belt... Edited May 20, 2017 by Plymouthy Adams Quote
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