Roofs and flat roofs
A secret valley behind the parapet was not seen from the ground. Which rainwater path is still unknown?
The rainwater path along that secret valley is still unknown. A valley hidden behind a parapet cannot be judged from the ground, and this survey did not see it from a higher point or from a void that opens onto it. What remains unknown is whether the valley gutter is blocked, split, flat or actually discharging as it should. Outlets and the junctions with the slopes were not in view. The report can say the valley exists and was not inspected. It has not decided that rain from those slopes reaches a working outlet.
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?
A secret valley is a gutter formed where slopes meet behind a parapet, often invisible from the street. Leaves and a failed liner collect there, and water then finds a joint, a crack in the parapet or the head of a wall. From the ground the surveyor may see a ceiling stain or a mark on the parapet and still not see the gutter that caused it. Unseen means the path is untraced. It does not mean the valley is sound because no drip was watched during a dry visit.
Ask the seller for any roof invoice that mentions this valley, and tell your solicitor the rainwater path was not inspected. If you need it known, the next step is safe access so the gutter can be seen, which this visit did not have. Do not describe the roof as cleared because the elevations looked even from the pavement. A lender should see a limitation, not an implied clean gutter. The survey has not specified a new liner and has not cleared one.
What should you ask your surveyor?
- Is there staining inside that lines up with this unseen valley?
- Was any outlet at parapet level visible, or was that hidden too?
- What access would a later inspection need that this visit could not take?
What are the typical next steps?
- Treat the secret valley as not inspected, whatever the street view suggested.
- Ask the seller when that gutter was last cleared or relined.
- Arrange access that looks into the valley if the rainwater path must be seen.
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 a dry ceiling clear the hidden valley?
No. A valley can be blocked and still not show a stain on the day, especially in dry weather. The ceiling records the room below, not the gutter behind the parapet. This visit did not see the valley. A dry ceiling does not trace the rainwater path and should not be written up as if it had.
Can binoculars from the garden finish the inspection of that valley?
Only if they truly see into the gutter. A secret valley behind a parapet is often still hidden from the garden, which is why it was not seen from the ground. Guessing the liner from a glimpse of tiles is not an inspection. Access that looks into the gutter is the step this visit could not take.