One of you goes up on the roof and the other stays in the attic to see if they can spot any leakage.
Quick patch roof leak.
Start low soaking the area just above where the leak appears in the house.
Once the leak is found push a nail up through the hole to mark its location for rooftop repair.
Sun exposure and heat especially during the summer can cause the rubber boot to crack creating the space for water to leak in.
Unfortunately the rubber boot damage often becomes the main cause of roof vent leaking.
Run water on the outside with a hose.
With the help of a friend use a garden hose to try to discover the leak s source.
It may not be a direct line but it will always be above the ceiling leak location.
If a leak is difficult to find enlist a helper and go up on the roof with a garden hose.
Isolate areas when you run the hose.
The nail will provide a path for the water.
Step 2 place a bucket underneath the nail to catch the water as it runs down the nail.
Have one person climb on the roof and spray water above the suspected leak location.
The person in the attic watches carefully while the one on the roof floods the roof with the hose starting at the bottom the eaves and slowly working uproof until water from the leak appears in the attic.
Start with the area where the leak seems to be coming from.
Look above the ceiling leak point and scan the sheathing leading towards the peak of the roof.