Can I apply roofing tar over shingles to seal a leak?
If you have a simple leak in your roof and know exactly where it is, then you can apply roofing tar over the affected area to create an effective patch. The preferred method, though, is to either replace the shingles that are leaking by removing the damaged shingles and replacing them and the roofing felt underneath or by lifting the row of shingles just above the damaged point and adding new shingles and roofing tar to completely seal the leak. If the roofing is on the old side, you may consider replacing the roofing shingles and felt (the black tar paper that goes underneath). This will probably save you time and more frustration in the long run.