We run across this all the time…a leaky roof that was repaired with roof tar or another cheap sealer…
In the hot summer, most of the black tar you buy in buckets and cans and even some of the white and silver products, simply will not hold up to the heat. It begins to break down after only 1-2 years.
This patch was done just 2 years ago and is already cracking. Water had begun to leak back into the house.
This is one of the great products that seems to actually work, I had a report this morning from a friend that said that after applying this product and letting it dry a couple days, they could put their bare skin against it without getting burned in direct sunlight in 100+ degree weather!
It is a great product for sealing roof leaks as well.
The only thing you may want to be aware of is that won’t match your roof, so take care to use it where it won’t be seen by people passing by..