A three-storey townhouse concentrates risk in a few specific places: the party walls it shares with neighbours, the single stair core serving every floor, and the top of the building where rainwater goods and roof condition affect everything below. A survey needs to trace problems through the stack rather than treat each floor in isolation.
Age matters here — a Georgian townhouse and a modern equivalent share the same basic plan logic but very different construction, so it's worth understanding both the building's actual age and its likely construction before reading the survey findings.
Party walls and structural movement
Cracking near party walls is a common flag on terraced townhouses and can indicate anything from normal historic settlement to active movement affecting a neighbouring property as well as this one. A surveyor will usually recommend monitoring or a structural engineer's opinion where cracking is more than hairline or appears recent.
Where the property has had structural alterations in the past — a chimney breast removed, an opening formed — the survey should note whether adequate support was provided, since inadequate historic alterations are a genuine and fairly common finding in this house type.
Roof, rainwater and the top of the stack
Given the height and narrow footprint of a townhouse, water ingress problems often originate at roof or parapet level and travel down internally before becoming visible on a lower floor, which can make the true source of a damp patch harder to pin down than it first appears. A survey flagging damp on an upper floor is worth cross-referencing against roof and rainwater goods condition rather than assumed to be a separate issue.
Blocked or undersized rainwater goods on a tall building are a common and often underestimated cause of recurring damp, and a flagged item here usually means a straightforward but necessary repair or replacement rather than anything more serious.
Suspended timber floors and ventilation
Timber floors at ground level in older townhouses depend on adequate underfloor ventilation, and blocked or missing airbricks are a frequent flag leading to damp and, in more advanced cases, rot in joist ends bearing on external walls.
A flagged rot issue in floor joists means the affected timber needs proper investigation and, where necessary, replacement — this is a job for a specialist, and the extent isn't always obvious until floorboards are lifted.
Services and fire strategy
On a three-storey property, the survey or an accompanying assessment should note whether the escape route down the single stair meets reasonable standards for fire safety, particularly for houses converted into flats in the past, where a much stricter fire strategy applies.
Old wiring and plumbing, particularly where a townhouse has had incremental piecemeal upgrades over decades rather than a coordinated rewire or replumb, is a common flag and usually points towards a full services renewal being the sensible long-term option rather than further patching.
Common questions
Is cracking near a party wall always serious?+
Not always — some degree of historic settlement cracking is common in older terraces, but anything beyond hairline cracking, or cracking that appears active or recent, should prompt a structural engineer's opinion before you commit to purchase.
Why would damp on the middle floor be caused by the roof?+
In a tall narrow building, water entering at roof or parapet level can travel down within the wall or party wall structure before showing as a damp patch several floors below, which is why tracing the actual source matters more than treating each floor separately.
Has the property previously been converted into flats?+
Check the title and any planning history — a former conversion back to a single house needs confirming that fire separation and escape route changes were done properly, since remnants of a flat conversion can leave compliance gaps.
Get a pre-purchase assessment for a townhouse
We'll trace flagged issues through the stack with you and set out a clear written summary of likely work.