Looked at a 17 Year Old Roof Yesterday

I looked at about a 1,000 SQR roof we installed 17 years ago in Dallas. It was over a gravel BUR and consisted of: 1. Flood layer of cutback mastic. 2. 1 ply of DuPont Sontara polyester fabric. 3. Flood coating of cutback mastic with white ceramic granules installed.

The roof looked so good that I called my dad to ask if we'd redone it in recent years. Nope, the roofs is 17 years old and looks like it's 1-2 years old.

That is a lot of asphalt. Sounds kind of like the stuff that Mike from NZ did, but his was troweled on.

OS, there's a net weight LOSS on the deck of around 125 lbs per SQR. We vac off 250 and put back on 125. Thus weight is never a factor. On a 500 SQR roof, there is weight loss on the deck of 62,500 after our roof is installed.

On gravel roofs we install around 20 gallons per SQR, plus 1 gallon of aluminum.

If you are going over gravel, how many gallons per square are you using total. Do you vac it off first? That must weigh a ton applied!