When do gutters need replacing rather than cleaning?

Work out first whether the gutter is failing to hold water or failing to move it. They look identical from the ground and have completely different fixes.

Not moving it

• Blockage, which is the most common cause and the cheapest fix.
• Insufficient or reversed fall toward the downpipe, often the result of brackets sagging or a poor original install.
• Too few downpipes for the roof area, which shows up only in heavy rain.
• Downpipes blocked below the gutter, including in the underground line, which is invisible from above.

Not holding it

• Rust perforation, particularly along the back edge and in the low sections where water sits.
• Failed joints and stop ends, where sealant has perished.
• Corrosion where dissimilar metals meet, or where the gutter has been in contact with treated timber.
• Physical damage from ladders, branches or hail.

The part people miss

Gutter overflow that runs back against the fascia rots the fascia and can wet the wall below, and repeated overflow next to the house saturates the soil beside the footings. In reactive clay that is a genuine cause of foundation movement, which means an unresolved gutter problem can become a structural problem.