matthew howden
Hi Andrew. The bad news is that there is no long-term solution for patching up a flat roof. Once it starts to leak, anything other than a proper, professional repair is temporary. On the other hand, a very effective way to seal a leak on a felt roof is to find the leak, place little bits of hard bitumen along the crack and heat with a flame gun. As the bitumen becomes molten it flows into the crack as water would then sets hard again creating a seal. Again, this is not permanent. Other than that, there are plenty of bitumen based roof sealants that are applied as paint that work for a short while, available in b&q, wicks etc. Hope this helps Matt - A A Roofing
