Quick answer
Can blocked gutters cause damp?
Blocked gutters are one of the most common causes of penetrating damp in UK homes. Overflowing water saturates the external wall repeatedly, and once the masonry cannot dry out, moisture reaches internal plaster. Damp repair typically costs £1,000, £3,500 against £80, £160 for an annual clean.
£1,000, £3,500
Typical damp repair bill
£80, £160
Annual gutter clean
1 winter
How long saturation takes to show
How to tell gutter overflow is the cause
Internal damp caused by gutters almost always lines up vertically with an outside joint or outlet, appears on an upper wall rather than at skirting level, and worsens after heavy rain rather than in cold snaps.
Rising damp shows at the bottom of the wall; condensation shows on cold corners and around windows. If yours is high on the wall and rain-linked, check the gutter first, then read what a clean costs.