Can rain splashing off a gutter leave a mark at the base of the wall that looks like rising damp?

What is the fuller explanation?

Gutters overspill when they are blocked, undersized for a downpour, or jointed so that water shoots against the brick. The splash wets a band low on the wall, which is exactly where people expect rising damp. Outside, you may see green staining or eroded mortar in that splash zone, often under a valley or a stopped end. Inside, the plaster can stain at a similar height. A true groundwater problem is not confined to the bay under a leaking length of gutter. A surveyor at ground level can often see the gutter defect more clearly than the top of the roof.

The inspection does not water-test the gutter and does not measure its fall. A dry day does not clear it. A home survey also does not guarantee the concealed fixings. If the report shows a low stain and a defective gutter in the same place, the first repair is the gutter. An injected course behind a wall that is still being splashed will not stay dry. Keep a downpipe that simply discharges at the foot of the wall as its own detail. Splash from the gutter onto the face is this question.

What should you ask your surveyor?

• Does the low stain sit only where the gutter overflows?
• Could you see the gutter from the ground, or was it hidden?
• Is the rest of the wall base dry?

What are the typical next steps?

1. Photograph the gutter and the low stain as one problem.
2. Do not inject a damp-proof course under a length of wall the gutter is splashing.
3. Clearing and realigning that gutter is the first conversation, not a new course.

Costs vary with the building and with who you instruct. Where this page does not cite a published figure, ask the surveyor, a relevant specialist, or your solicitor for a written quote. Do not treat a forum average as the price.

Also asked about this

Which pages should you read next?

• If only one elevation is wet, and only after wind-driven rain, is that rising damp?
• If a roof-window blind comes down wet, should every roof slope be treated as failed?
• The door sill is soft and the frame above it is hard. Which piece of timber has the survey called decayed?
• Guide: What does damp mean in a home survey?
• All UK home survey questions

Sources

• RICS: RICS Home Surveys (Home Survey Standard)
• Property Care Association: Structural problems, including damp, dry rot, wet rot and woodworm (homeowner advice)
• GOV.UK: Damp and mould: understanding and addressing the health risks for rented housing providers