Hi folks...my roof sprang a sudden large leak a few rainstorms ago. The
water is coming in at the end of the roof sheathing where a dormer is
cut in, right next to the chimney. There is no visible flashing, just a
few inches of tar where the roof & chimney meet. It looks solid, no
cracking or peeling, but a lot of water is getting in somewhere.
The mortar on the chimney is in pretty bad shape especially at the top.
I'd have no problem believing the water was getting in through mortar
cracks and exiting under the tar. I'd like to seal this up before
tomorrow's start of 2 days of rain.
The house is 75 years old and in the northeast. Can I use type N mortar
or should I put a temporary seal up there and determine what mortar was
used originally? It's borderline as to whether type N or type O was
used. The stuff looks pretty sandy, but that could be weathering.