How to repair leaks permanently on flat roofs Karnak 19 Professional Grade Flashing Cement

Roof repair with the industry’s No. 1 choice of flashing cement – Karnak 19. The video demonstrates the surface preparation and application of Karnak 19 on a …
roofing repair nj



  1. Gallo Karnak guys, several attempt I made to contact you by mail. One question please do i have customer service dept?. I think so no. If you must reply to customer wish use your system. Let me know how this product available in India and how.

  2. I've had 3 roofers take my money over 8 years: The first one who put on the original, the second, (after the first one bailed on me), came back after the first few rains showed he really didn't fix the leaks and bailed on me, the third, actually did a good job and I called him back to fix another area, and after numerous calls and even 2 visits to the office never called me back and now his work is failing. I'm a little gun shy about handing over a few more thousand dollars to anybody else. Water ponds about 3/8" deep behind my scuppers. Will this product control standing water? Can it be built up to stop the ponding?

  3. Can I use this to cover the whole flat roof? I'm not sure where the leak is happening on the house. I'm thinking about caking it with this if it works…

  4. our roof is a plastic type, a deli that was originally mobile, it has a large fan for the range/Grill for the deli, it leaks no matter what, used a waterproof silicone but nothing simple seems to work, will this flashing be good on that roof?

  5. this may be a dumb question but why build a flat roof that can hold water ? why not angle the roof so water runs off I see with a flat roof you can save room by putting all the a c stuff on the roof

  6. It is about 54 degrees in seattle.  It was very difficult to apply and it didn't want to stick to the torchdown.  I put a very thick patch and was able to get it down.  Then when I put on the fiberglass it was sticking.  I hope this works.

  7. That is far from a permanent repair. The quality of the cement application was a fail and no granules to protect your repair from the weather. That repair will not outlast the life of the roof. I would have either torched a strip over it or used a modified adhesive with a cotton membrane and finished it off with granules. Several years later it would look as if it were a new repair. It takes more than just a good product to do good work.

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