This can be done by pouring a small amount of water over the area you suspect the hole in your roof is located and checking for the leak underneath.
Seal a leaking flat roof.
For a gap of 1 inch or less caulking or sealant is the best method of repair.
When the membrane is completely dry apply the appropriate roof repair material such as roof cement tar or peel and stick patch.
Some roofers also suggest using 6d roofing nails to secure the blister flaps.
Leaks in wooden roofs are commonly caused by a gap between the panels which move during expansion and contraction.
The patch should be adhered from the centre over the hole outwards with a firm hard roller.
A small patch can act as a permanent epdm roof repair for leaks and cracks.
If you take that step be sure to cover the nail heads with tar roof sealant or peel and stick flashing patch.
Do a small area at a time to really pinpoint the cause of the leak.
Step 2 fill a caulking gun with a watertight polyurethane or oil based sealant and hold it at an angle to insert the product directly into the gap.
Clean and dry the area you wish to apply flex seal.
Feathering or tapering the edges of thick but sound roof coating.