Flat roof leak

Dec 28, 2008 12 Replies

I have a flat roof of tar and areas of rubber torch down. What can be used in below freezing to fix a few leaks. Rubber torch needs above



55f, will that thin tar in a 5 gallon bucket at box stores work in winter, I know the thick mastic works when hot out but in cold it wont be pliable, and will anything bond in cold for DIY. A pro and tar truck would cost alot.

You can keep the bucket of roof cement inside in a heated area until you need to use it. A heat gun, or, if you're braver and careful, a propane torch, can be used to heat up the tar so it can get into the cracks better.

R

Positive building pressure.

Maybe some of the products designed for mobilehome roofs would work. Larry

Karnak # 19, winter grade, & fiber tape. The fiber tape is sold in 5 or 6" width.

You'll probably have to get this at a roofing supply house.

Roof cement is pretty thick even at 60f, its not cracks since I have gone over everything I just cant find these leaks, Its an area maybe

8x8 I need to coat, cement would hit the cold roof and air and be unworkable, Im sure my 250000 btu torch would just make a fire.

A roofing supply house would be where I would get the correct product.

Really need to consider a sloped roof. You can tar and patch forever and still have new leaks.

AMEN!! I fought flat roof leaks for years at our church and finally talked them into getting a slope on it. Problems solved. It doesn't need to be a big slope, just enough to get the water to run off. A 2' drop across 30' with commercial roll roofing & properly installed did the trick.

KC

A few years ago our county bit the bullet and did a multimillion dollar refit of the HS flat roof. They wised up and put a peaked roof (around 4 in 12 by the looks of it) over the flat roof.

Why architects design buildings with roofs gauranteed to leak is beyond me. I can see it for huge buildigns but in residences or reasonably sized ones it is asinine.

Harry K

If the flat roof has those little parapet walls, you can fake things with built-up contoured layers of foam insulation over the old deck, with the new membrane roof layered over it. Usually cheaper than adding a whole peaked roof, and the added insulation helps the HVAC load. Only hard part is adding the drains or scuppers to lead the water away.

-- aem sends...

The best would be a 7" R 7.2 foam roof that would give me R 50, but I bet it would be 15,000.00 or more. that is eventualy what I will do, its a large building.

I used to be the Chair of a Strata Council with 3 buildings. For emergency repairs I would put a liberal amount of dry concrete over the spot (flatten out about 1" thick). As long as the roof stayed wet the patch will hold. Then on the first dry day have the roof fixed.

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