Damp and moisture meters
What did the visit record about a picture rail and dado, about a salt band below the rail, and about whether the tide mark is damp or old decoration?
The visit recorded the picture rail and dado as mouldings, a salt band below the rail as a deposit that could be seen, and left open whether the tide mark is damp or old decoration. A rail and a dado are horizontal trims. A salt band is a crust or a line, not a cause. The survey has not decided on rising damp, has not mapped moisture through the wall, and has not said the decoration is a live tide rather than an old paint line. The mark stays unexplained.
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?
Picture rails and dados divide a wall into bands and protect the lower part. A salt band below the rail can be crystals from the masonry, a paint line, or both together. Hygroscopic salts can look damp in humid weather without any rising path from the ground. The visit recorded what showed. It did not plot readings up the wall, and it did not sample the deposit.
Tell the solicitor the rail, the dado and the band were described, and that the tide mark was not diagnosed. If you need a cause, a damp specialist can map the wall and the deposit. Do not treat a line under a picture rail as proof of rising damp, and do not specify a chemical treatment off this paragraph. The lender has the same undecided note. Decoration and any damp investigation stay separate from the home survey.
What should you ask your surveyor?
- Did you record the rail and dado as mouldings rather than as a damp test?
- Was the salt band left without a sample or a moisture map?
- Have you left open whether the tide mark is decoration?
What are the typical next steps?
- Record the band as seen, not as diagnosed rising damp.
- Ask a damp specialist to map the wall if you need a cause.
- Tell the solicitor the tide mark was not explained.
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 dado rail stop damp from rising past it?
No. A dado is a timber or plaster trim. It does not form a damp course, and the survey did not say it did. Salts can show above or below a rail for reasons that have nothing to do with the moulding. The trim was recorded. It was not tested as a barrier.
If the band is dry to the touch, is it only old paint?
Not necessarily. Some salt deposits feel dry and still mark the wall, and some old paint lines look like salts. Touch was not turned into a diagnosis here. The visit left damp and old decoration as alternatives. A dry finger does not close that question.