Where is my gutter leaking from?
Match where you see water to the likely cause before you call anyone.
Where the water appears tells you most of what you need to know. Check during rain if you can do so safely from the ground.
| Where you see water | Likely cause | Usual fix |
|---|---|---|
| Dripping from one point under the gutter | Failed joint sealant or a rust hole | Re-make joint or patch |
| At an internal or external corner | Corner mitre sealant has cracked | Strip and reseal corner |
| Running down the wall behind the gutter | Gutter blocked or without fall; water overtopping the back edge | Clean, reset fall |
| At the top of a downpipe | Blocked downpipe or failed outlet seal | Clear and reseal outlet |
| Along the whole front edge in heavy rain | Undersized gutter or too few downpipes | Add downpipe or upsize |
| Stain on the ceiling near an outside wall | Overflow into the eaves, or a roof or valley leak | Inspect urgently |
| Ceiling stain along a party wall or parapet | Box gutter leak or overflow | Box gutter repair |
Leaks that are not the gutter
Water tracking behind the gutter can also come from the roof edge: a missing eaves flashing, cracked bedding under the last row of tiles, or sarking that stops short of the gutter. If the gutter is clean and sound and water still appears behind it, the roof edge needs a look.
Why sealant alone rarely works
Gutter joints are held by rivets and sealed with silicone. Heat cycles work the joint until the old sealant lets go. New sealant over old does not bond. A lasting repair separates the joint, cleans to bare metal, re-rivets and reseals.
Next step: leaking gutter repair or box gutter repair.
Ready for a fixed-price gutter quote?
It takes about a minute, and there is no obligation.