Structure
How should you read a garden wall or a retaining wall in a home survey?
A retaining wall holds soil back. A garden wall usually does not. A home survey can describe cracks, lean and blocked weep holes it could see. It does not design the wall, calculate the soil pressure, or decide which neighbour must pay. Movement in that wall is not automatically subsidence of the house.
Last reviewed 24 October 2026. Written for buyers in England and Wales unless a source says otherwise. No named surveyor has signed this page. It is general guidance, not a report on your house, and not legal advice.
Which building is being described if only the garden wall is out of line?
The house and the garden wall are different structures. A wall at the end of the lawn can lean, crack or lose a pier while the dwelling stays plumb. The survey should say whether the main walls were out of line as well. If it only describes the garden wall, do not copy that sentence onto the foundations of the house.
ABI's account of subsidence is about the ground sinking beneath a building. A cracked brick pier in a flower bed is not that finding unless the report ties it to movement of the house. Ask which element the comment sits under.
What can the surveyor say about weep holes and water behind a retaining wall?
A retaining wall with soil against it needs somewhere for water to leave. Weep holes that are blocked, missing or painted over are a visible detail. The survey can record that. It cannot measure the pressure of the soil, and it cannot see a drain behind the wall if the face was not opened.
Approved Document A is guidance for building work on structure. It is not a rating of this wall and it is not a design the surveyor has signed. If the wall is bulging, the next step is someone who designs retaining walls, not a guess from the lean alone.
Can a home survey decide who owns or must repair a boundary wall?
No. Ownership sits in the deeds and the plans, which the solicitor reads. The Party Wall etc. Act is a process for certain work on boundaries. It is not applied by a condition rating. The survey can say the wall leans and which side the ground is higher on. It cannot send the bill to the neighbour.
A wall that holds up a neighbour's drive is still a condition note plus a legal question. Keep them apart. Do not tell the neighbour the survey has found them liable.
Common questions
The garden wall has no piers and it is cracked. Is the house unsafe?
The note is about that wall. Missing piers explain why a long brick wall can crack. They do not, by themselves, mean the house foundations have failed. Read the comments on the main walls separately.
Concrete sleepers hold the patio up and one has rotated. Has the patio been designed in the report?
No. The survey can see the rotation. It has not calculated the retained soil and it has not approved the sleeper system. A rotated sleeper is a reason to ask a designer, not a price printed by the survey.
The front wall holds the pavement up. Is that a highway matter?
It may become one, and the survey does not act for the highway authority. It can describe the lean and any crack. Who must repair a wall that supports a public pavement is a question for the solicitor and, if needed, the authority. It is not a condition rating.
A tell-tale is fixed to the house wall, not the garden wall. What can the survey read from it?
Only what is on it today, if anything is written there. A tell-tale without a log does not prove the crack has stopped or that it is still moving. The survey does not inherit the seller's memory of the readings.
Weep holes in the retaining wall were painted shut. What was lost?
A visible route for water out of the back of the wall. Paint does not prove the wall is dry inside. It shows those holes are no longer open. The survey has not pressure-washed them and has not dug out the fill.
A crack runs from the retaining wall into the house plinth. Is that one defect?
It is a crack that continues, which is worth saying. It is still not a finished diagnosis. The survey should describe the path. It has not monitored it and it has not decided the cause is the retained soil rather than the house foundation, or the other way round.
Should you budget to rebuild every leaning garden wall?
No. Some leans are old and idle. Some are progressing. The report's job is to say what it saw and whether it wants a specialist. A rebuild price comes from a contractor who has designed the replacement, not from the word leaning.
Does the Party Wall Act start because the survey mentioned the boundary?
No. Mentioning a boundary wall does not serve a notice and does not appoint a surveyor under that Act. If you later excavate or build on the boundary, that is a separate legal process. Your solicitor, not the condition rating, tells you whether it applies.
Sources
- House surveys: the costs, types and benefits of an RICS home survey — RICS
- Approved Document A: structure — GOV.UK
- Party walls and building work — GOV.UK
- How subsidence can affect your home — Association of British Insurers
Key facts
- Two kinds of wall
- A retaining wall supports a higher level of ground. A freestanding garden wall does not. The survey should say which it is describing.
- What was seen
- Lean, cracks, missing piers, blocked weep holes, and whether the house itself is still in plane.
- What was not done
- No soil-pressure calculation, no ownership decision, and no instruction to a neighbour.
- Subsidence
- ABI describes subsidence as the ground sinking under the building. A garden wall leaning on its own is a different sentence.