Roof leaks are confusing to diagnose. Various conditions can cause roof leaks and the origination point may be difficult to detect. Roof leaks must be repaired from the outside to ensure the problem is corrected. However, when it is not practical to climb up on the roof to fix a leak, such as during the winter months, you can repair a leaky roof temporarily, from the inside, if you can determine where the leak is occuring from the underside of your roof.
Seal the Leak
Locate the source of the leak by examining the underside of the roof from within your attic or crawl space.
Shine a flashlight along the underside of the roof and look for a hole in the roof as well as areas that are wet or have been darkened by moisture.
Mark the areas that appear to be leaks with chalk so they will be easier to find later when making a permanent repair.
Let the wet areas dry and then apply the patch to the underside of the roof with a putty knife. Use enough of the roof patch to liberally cover the leaky area.
Use a caulking gun to apply caulk to seal any holes that appear in the roof. Use the putty knife or your finger to spread the caulk around to cover the hole.
Divert the Water
Insert a nail in the hole where water is leaking through the roof. The nail will provide a path for the water.
Place a bucket underneath the nail to catch the water as it runs down the nail.
Patch the hole from the inside as soon as the area is dry enough for the caulk or roof patch to be applied.