No clue where it came from. I’ve been using this for about four years now.
ptah
joined 1 year ago
It lasts forever with regular maintenance. I moved into a house with a slate roof that’s 96 years old. We just have a roofer come out and replace a few cracked tiles every year. Not necessarily any cheaper but the cost is spread out and it seems less wasteful.
You can actually type the math into DDG and it will do it for you. Just search for “1.2+5.6+10” (I’m not sure how DDG handles the comma versus period but I would expect that it would adapt to your location)