It may take some time for the water to appear but if it appears during or after a rain the roof is the place to look for the source.
I ve got a leak in my roof.
And just one rusted out nail can cause your roof to leak every time it rains.
Follow damaged insulation back to the source of the roof leak.
If your gutters clogged up with debris or leaves water will stop flowing off the roof.
The leaking occurs during or shortly after a rainfall.
Nail pops can also occur where the a nail or multiple nails push up and out causing the shingle above to lift eventually penetrating the top shingle and causing a leak.
Contain the leak if you find water dripping from a bulges or discoloration in your ceiling it s likely that water is pooling on the other side of that bulge or dark spot.
Consider getting a gutter cover to help keep the gutters free of debris.
Run water over the low side of the penetration for several minutes while the helper watches for any water droplets.
Finding the actual spot where the roof leaks is difficult because water can enter the roof in one place and run down to another before it starts soaking into the ceiling.
You know the roof is bad if shingles are missing or obviously damaged or when water stains the ceiling or walls.
The underside of your roof may be obscured by insulation and that s actually helpful for finding the roof leak.
In addition roofing system leaks will make themselves known through other symptoms.
Use enough water to mimic heavy rains.
Grab a bucket trash can or some other container and place it under the site of the drip or suspected leak.
The goal is to find the leak before the entire roof goes bad.