What do trees near a house mean in a survey?

How can a tree affect the ground under a house?

The Association of British Insurers explains subsidence as the ground beneath a building sinking and taking the foundations with it. One mechanism ABI describes is clay that shrinks when it dries. Trees and shrubs can draw water out of that soil near the foundations, which adds to the drying. That is a risk factor on clay, especially in a long dry spell. It is not a statement that every tree, on every soil, is damaging the house next to it.

Heave is the ground moving the other way, including when a large tree is removed and clay takes water back up. ABI treats subsidence, heave and landslip as related insurance perils, not as the same crack. A survey that says “tree close to the building” is flagging the risk factor. It is not, on its own, a claim form and not a specification for felling.

Does a nearby tree prove the crack is subsidence?

No. The tree can be innocent. The crack can be an old lintel, thermal movement, a rusting wall tie, or settlement from when the house was new. The subsidence page is where those words are separated. A surveyor looks at crack pattern, distortion, the soil they can infer, drains, and vegetation. They do it in a visit, not over a season of monitoring. If they suspect movement related to the tree, the honest result is further investigation, often a structural engineer and sometimes a drain test or an arboriculturist. The tree’s presence is not that investigation.

This guide does not give a safe distance in metres. Distance, species, height, clay, and the depth of the foundations all matter, and a generic metre rule pretends they do not. If someone offers you a distance as if it were law, ask which investigation of this building it came from. Do not negotiate a felling cost off a number this page has refused to invent.

Why is Japanese knotweed not the same issue?

Japanese knotweed is a plant you must not cause to spread. GOV.UK’s guidance is about stopping it spreading, including through soil and waste. That is a different problem from a tree drawing water from clay. A stem in the garden is not evidence of foundation shrinkage, and a clay-related crack is not evidence of knotweed. Use the knotweed page for identification and for the rules on disposal. Do not let one word, “vegetation”, collapse the two into a single scare.

• Tree and shrub water uptake on clay: an ABI risk factor for subsidence, not proof about this crack.
• A crack: described by the survey. Cause unproven until someone investigates it.
• Japanese knotweed: a GOV.UK biosecurity problem. Different controls, different advice.
• Drains: leaking drains can wash out or wet the ground. They are not the tree. See the drainage page.
• No metre distance is given here. Do not import one.

What will the survey not do to the tree?

A Home Survey does not prune, pollard or remove the tree. It does not produce an arboricultural method statement, a felling licence application, or a tree-preservation order check unless the report says that separate work was included. Tree preservation and conservation-area controls are legal questions for the council and your solicitor. Cutting a protected tree because a survey mentioned it can be an offence. The condition rating tells you how seriously the surveyor takes the building defect. It is not a works order for the garden.

If the report recommends a specialist, instruct that specialist before you agree a price chip for “the tree”. An engineer may say the crack is unrelated. An arboriculturist may say management is possible without felling. ABI’s description of clay and water is the mechanism to understand. It is not a verdict on the sycamore outside this window.

Common questions