|Posted on Thursday, April 22, 2004 - 04:41 pm: ||
I am giong to start a long-term restoration of a 80 year old graduated Sea Green roof. All of the slate in the 16 valleys were originally set in place with mortar and the joints were pointed. My question: is it necessary to repoint the joints and re-set the mortar bed or can this be flashed with lead or copper to prevent any future problems. There are currently no leaks in the valleys, but there has been improper repairs done to them over time (i.e tar, silicone etc.)
|Posted on Saturday, April 24, 2004 - 12:26 pm: ||
You can install a sheet of flashing in each course underneath the slates. 20 ounce is preferable. The flashing should overlap each other by about 6 inches, depending on the slope. There is a picture of this in the Slate Roof Bible, 2nd edition, page 278.