Age and type of house
Roughcast sounds hollow over a stone wall when tapped at one patch. Has the survey diagnosed the whole elevation, or one area it could reach?
Only the patch of roughcast that sounded hollow was tested, not the whole elevation. A hollow note means that patch has parted from the stone behind it. The surveyor reached one area. The rest of the wall was not given the same tap, or could not be reached, and it has not been diagnosed. A visual survey records the hollow it found. It does not stretch one sound into a failed coat across the facade, and it does not specify a new roughcast.
Last reviewed 24 October 2026. Written for buyers in England and Wales unless this answer says otherwise. No named surveyor has signed this page. It is general guidance, not a report on your house, and not legal advice.
What is the fuller explanation?
Roughcast hides the stone until it comes away. A hollow patch may be a small detached bubble, or the edge of something larger. Telling those apart means more tapping than this visit claimed to finish. Stone you cannot see may be wet, cracked or perfectly serviceable behind coat that still sounds solid. Do not write the unseen elevation into the sentence that describes one patch the surveyor could reach and tap.
A renderer or a mason can tap a proper sample of the wall and then say how far the detachment goes, and what the stone is like behind the hollow patch. Ask the quotation to mark that area. A figure for hacking off the whole house is not the finding unless their own note shows hollow coat beyond the patch. The report's reach is the patch that was tapped. Keep the price inside that reach until evidence extends it.
What should you ask your surveyor?
- Where is the hollow patch, and how large an area did you actually tap?
- Which parts of the elevation could you not reach?
- Are you diagnosing the whole wall, or the one patch that sounded hollow?
What are the typical next steps?
- Mark the hollow patch, and do not redraw it as the entire elevation.
- Ask a renderer to tap beyond that patch before pricing a full removal.
- Do not specify a new coating from the survey sentence alone.
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
Does one hollow sound mean all the roughcast has failed?
No. The hollow is the patch that was tapped. The rest of the elevation was not diagnosed, and one sound does not regrade the whole wall.
Has the stone under the hollow patch been inspected?
No. The roughcast still covers it. Hollow means the coat is loose there. It does not describe stone that was not exposed.