Flat roof problems

[C. Adam Barney]

I have a house with a low-slope roof that comes down to a attached flat-roof garage that's been converted in to a family room. Since buying the house 3 years ago, I've been repairing leaks constantly along the seam between the low-slope and flat roofs. I'm tired of it, and would like to take some broader action to fix the problem. The only leaks we've had have been along that seam. The current roof is asphalt roll roofing.

Is there a coating that I can apply that will fix this problem? Should I replace the roll roofing on the flat portion, or maybe put another layer of roll roofing on? Am I completely off track with these ideas?

Thanks for any help you can provide!

Adam

[EagleMtn]

Your leak is probably from a higher portion of the pitch roof, but coming through at the seam with the flat roof. Your flat roof is probably fine.

Bryan

[C. Adam Barney]

Can you point me to information about "properly flashing" the flat roof to the sloped roof? I can't really afford to hire a roofer to do this, but I do pretty well with home improvements as long as I have decent information.

Thanks for your quickk reply!

[C. Adam Barney]

I tried finding the source of the leak with a garden hose a few weeks ago. I did not wet the pitched portion of the roof at all, just the flat roof portion, and was able to get the water flowing inside. I only watered the seam portion, and it took quite a while for the water to start coming in inside - so I know the leak is along the seam, just can't pin down where.

[EagleMtn]

In that case, you are probably correct. The leak is in the seam.

If the flat roof is EPDM, looks like bicycle inner tube material, you can glue another piece 6" wider on each side of the seam. Use If the material looks like it is a tar sheet, you can use torch-down sheet 6" wider on each side also.

I think you said the material is roll roofing. Were these simply nailed down? Maybe it just needs a little tar and mesh (tar coated baddage looking thing.

Looks like I need to see the problem to really help you. PerhapsIf you were in the DC Metro area, you could get some material from Washington Roofing or Bradco Supplies.

Good luck with it.

Bryan

[tom]

Just remember that water _usually_ flows downhill. A properly flashed pitch change will take into account the local climate, the insulation/ventilation, the pitch and the materials you use. In a nutshell, you'd tear off the lowest area of the sloped roof, install the new flat roofing material up to where you stopped tearing off, then install new or dependable sloped roofing material over the new flat material starting just a few inches above the pitch change. Simple, no? Tom

[Colbyt]

A rubber roof over the flat surface and properly flashed to the low slope roof should solve your problem for many years to come.

Another layer of half lap roll roofing properly flashed may solve your problem for a few years.

[Colbyt]

I don't have any links to share. The roll roofing or metal flashing should extend at least 6" under the shingles above and 12" over the roll roofing (or the top strip of roll roofing). On really shallow "flat roofs" it should be glued down to the flat roof . Water can actually run uphill for a slight slope. A liberal use of roofing cement to adhere the layers together will work for a few years.