Condition ratings
Ridge mortar is missing in patches and the ridge tiles have not shifted. Is that automatically condition rating 3?
Not quite. Ridge mortar missing in patches, with the ridge tiles still unmoved, is not automatically rating 3. Empty mortar is a real gap at the ridge, and it can let weather in later. Tiles that have not shifted are a calmer observation than a ridge that has walked. The number follows how serious the surveyor thinks that gap is, not a rule that any missing mortar is the top mark.
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?
Ridge mortar is the bedding that holds the ridge tiles along the apex. Patches missing, while the tiles themselves have not shifted, is a weathered joint rather than a ridge that has come loose. Rating 3 is for a defect that is serious, urgent, or both, and it is the cue for written quotations before you legally commit. A gap in mortar, with the tiles still seated, is often a repair that is not serious or urgent, which is rating 2, or even normal maintenance if the surveyor says the loss is slight and no repair is currently needed, which is rating 1. Automatic promotion to rating 3 is the mistake.
The what to do now note advises you, the buyer, about whatever number was actually given. It does not invoice the seller for a new ridge because some mortar has gone, and it does not apply the rating 3 quotation step to a defect the surveyor left at rating 2. Look along the paragraph for slipped ridge tiles, a sagging line, or daylight under the apex. Those would be a different conversation from patches of empty joint. If none of them is written, keep this as a mortar note and ask a roofer whether repointing the ridge is the work, rather than taking the ridge off.
What should you ask your surveyor?
- Have any ridge tiles actually moved, or is the loss only mortar?
- Which rating did you give this ridge, and which definition does it match?
- Is the rest of the ridge, beyond the patches, in a different state?
What are the typical next steps?
- Do not call missing mortar rating 3 unless the report does.
- Ask a roofer about repointing before you assume the ridge must come off.
- Keep the ridge note separate from the rating of the slopes.
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
If one ridge tile has slipped as well, does the mortar note become rating 3?
Not by addition. A slipped ridge tile is its own defect. Ask the surveyor whether that changes the rating they gave.
Does hip mortar follow the same reading?
A hip is a different edge. Missing hip mortar is not the ridge's number unless the report groups them and says so.