Low-Slope Roof Repair

I live in a house my parents bought in the late 1940's. In the back is a low-slope roof. The low-slope portion has been untouched since at least the 1960's if not the 1950's.

This summer I had a new roof installed on the rest of the house. The roofer told me he would not do the low-slope part. I told him that suited me just fine because it never gave me any trouble and had been zero maintenance.

It turned out that he sub-contracted out the entire job. He didn't watch "his guys" and they roofed the entire roof including the low- slope portion.

The manufacturer said they would not warrant the low-slope portion because of insufficient slope. Another roofer told me the roof will not last.

Problem: No one knows how to put the roof back the way it was. Everyone I have consulted about the roof says that the technology is lost and that any roof that is put there will have to be coated every three years.

Have we regressed that much? Is it impossible to construct a low-slope roof (1.75 in 12) so that it does not need to be maintained?

Reply to
Al
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EPDM is condemned in this article.

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is condemned in this article. "Colbyt" wrote

Reply to
John B

Our back roof was only 1.8 inches per foot like yours, and was shingled with comp. roofing, which failed within two years. Shingles are not applicable, as most manufacturers will void their guarantee for shingles if pitch is less than 4 inches - read the left over package covers on the product..... So we had roof stripped to wood decking, then had a five layer non-shingle commercial roof put on. You need to get better info, and keep away from the idiots that do jobs poorly and give erroneous advice (eg the technology is lost!) . Get local references from neighbors you know, and use local roofers that have high volume business and good reputation, with warrantees. Our roofer had a 3 year unconditional warrantee, but de facto much longer, as he is known to correct mistakes way behond this period. On the steeper 4 inches per foot front roof, we got 30 year shingles. Anyway, the low pitched roof we had put on was first underlain by fiberglas/rubberized padding or blanket, then three layers of lapped hot tar mineral felt, followed by a walkable mineral grain surface, hot tarred to the tarred 3-ply felt underneath. It should be good for 20-30 years, and has

9 years on it so far, with little signs of aging. I hate tar and gravel, as it is hard to diagnose leaks, and is more prone to damage by walking.
Reply to
Roger T.

we had a low pitch roof when i was a kid. it used 'rolled' roofing. i cant imagine they quit making it...

randy

Reply to
xrongor

I don't know what it was other than not shingles. If I knew, I wouldn't be as concerned. If I knew I could get more of it, I wouldn't worry at all.

I d> Curious / What kind of roofing material is on it now & what was there? >

Wasn't asphalt shingles.

- Torch-Down modified bitootem(sic) is popular

Could be this

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Reply to
Al

Low cost solution is half lap roll roofing with full cement undercoat.

10-15 years.

Modern far superior product is full glue down EPDM. Think big rubber sheet and you understand what this is. Not sure what the actual rating is but I would guess 25-30 years.

Colbyt

Reply to
Colbyt

I also have a roof problem. My sun porch drops one foot in a distance of sixteen feet. The inside ceiling is interior drop ceiling asbestos roof panels and they leak continually. The exterior is the wavy metal and I am looking for something to put on top of it. The frame is metal underneath the metal roof, so I would rather not try to deck it. any suggestions. Will rolled roof go over the corrugated roof, or will I have to deck it? Thanks Al

Reply to
The hooligan

Curious / What kind of roofing material is on it now & what was there?

Reply to
bumtracks

I did read it - several times. The shingles were made by Tamko.

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Somewhere in there the warranty said it was good down to 2" per foot. But, it doesn't really matter since the slope was about 1 5/8" per foot.

Thanks for the information. Now, I know something can be done. I have had two doses of misinformation. The second "lost technology" guy does have an excellent reputation. However, it seems like he recently took over the business from is father and is a bit young.

We are just getting out from under a foot of snow right now. I don't know what actually was done to the roof. I am hoping at least part of the original roof is still there so I can see how it was done. If not, I can use your information as an IQ test.

Reply to
Al

Travis is giving excellent advice. That roofhelp website is really good, and reminds me that I used all the wrong terminology in my earlier comment. Ok, to repeat, On my 1.8 inch pitch, I had a built-up roof applied. Fiberglass basesheet, then three ply hot tarred roll roofing (each successive layer covers 2/3 of underlying layer, so that you get 3 plies, net), followed by a tarred-on mineral surfaced capsheet. Worked like a dream, and is very sturdy and walkable.

Reply to
Roger T.

That article does not condem EPDM itself at all, really. The problems encountered were found to be due to installation issues. Read it again.

BB

Reply to
BinaryBillTheSailor

You've got a problem. Instead of shingles, at a miniumum your low slope roof should have been recovered with BUR (built up roofing), a multi-layer covering that is designed just for this application.

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Your shingled low-slope roof won't last long, and worse yet, could begin leaking immediately due to the lack of a sealed membrane between the shingle and the deck. This isn't too much of a problem on sloped decks because the water runs down the underlayment surfaces. But on a flat (or near flat) room the water can back up under the underlayment laps, and presto, you've got leaks.

Another problem you should be aware of: when you replace the flat roof, you need to make sure it is "tied in" to the shingled roof above / below it. This is not a trivial job and requires someone who is really good at reroofing. Obviously, not your previous contractor.

Depending on how long you want the new flat roof to last, you should ask for a multi-ply (3 or more) BUR. There are other technologies available for this application, but IMHO hot (asphalt) applied BUR has been around for a long, long time and has a good reputation.

Hope this helps.

Reply to
Travis Jordan

Any port in a storm, friend, but you'll want your roofing membrane to be supported at all points. Think about roofs in commercial buildings. They are rather flat. Plywood sheeting is attached to rafter stock. Then roofing material is laid upon that.

Reply to
John B

Now how do you suppose they do all those office buildings and warehouses that have virtually FLAT roof? Some are tar and gravel, but these days most are rubber membrane roofs that will last virtually forever. That's how I had my home's nearly flat roof done and it works perfectly and guaranteed for as long as I own the home.

Reply to
curmudgeon

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