Almost every gutter fault is one of four things: a failed joint, a dropped or missing bracket, a fall running the wrong way, or a run that is simply worn out. Telling them apart from the ground is difficult and matters a great deal, because the first two are small repairs and the last two are usually a replacement run.
How much to repair a gutter joint: joints are most of it
Plastic gutter systems join with a union containing a rubber seal, and those seals harden and shrink with age and ultraviolet exposure. A dripping joint is the commonest gutter fault in Britain and the cheapest to fix, usually by replacing the union rather than sealing over it. Silicone smeared into a failing union is a temporary measure that makes the proper repair harder later, and finding it is a fair sign of how the property has been maintained.
Brackets and the sag
Brackets are screwed to the fascia at intervals, and when one lets go the gutter sags and water pools instead of running. The cause is often the fascia rather than the bracket: a soft, rotten board will not hold a screw. That is the point at which a gutter repair turns into a fascia question, and a contractor who replaces a bracket into rotten timber has sold you a repeat visit.
Falls, and the fault nobody sees
A gutter must fall towards its outlet. Runs that were set badly, or that have moved as the building has, hold standing water, which is heavy and accelerates joint failure. You can often see it after rain as a line of water sitting in one part of the run. Correcting a fall means resetting the brackets along the whole length, which is closer to a replacement in labour even where the gutter itself is reused.
Valley gutters are a different animal
Where two roof slopes meet, or where a parapet runs along a boundary, the valley or box gutter is a lined channel rather than a plastic run, and it is usually lead or a single ply membrane. They fail at laps, at the junction with the tiles, and where debris has dammed them. A failure here puts water directly into the structure rather than down a wall, so it is urgent in a way a dripping union is not, and it is specialist work.
Guttering repairs cost against a new run: when to stop repairing
If you are on the third union in two years, if brackets are pulling out because the fascia has gone, or if the system is an old cast iron or concrete one with several defects, the sensible spend is a new run rather than another repair. Ask the contractor to price both and to say plainly which they would do on their own house.
Questions people ask about gutter repair cost
Can a leaking gutter joint be sealed rather than replaced?
It can be, and on a modern plastic system replacing the union is usually similar in cost and lasts far longer. Sealant is a reasonable stop gap in bad weather and a poor permanent answer.
Why does my gutter overflow in heavy rain only?
Either the run and downpipe are undersized for the roof area draining into them, or a partial blockage is restricting flow that normal rain never tests. Both are diagnosable and only one is solved by cleaning.
Is gutter repair urgent?
A dripping joint is not an emergency and is not harmless either, because persistent water against a wall causes damp and rots the fascia behind it. A failed valley gutter is urgent because the water goes into the roof structure.
Who repairs cast iron guttering?
A roofing or specialist guttering contractor rather than a general cleaner. Cast iron is heavy, needs proper access and is often on older or listed property where replacing it with plastic would be inappropriate or not permitted.