Roofs and flat roofs
Nail sickness is named on the north slope only. Why should a quotation for the south slope not be treated as the answer to that note?
Only the north slope is named in the nail-sickness note, so a quotation for the south slope does not answer it. Nail sickness is the failure of the nails holding the slates or tiles on the slope the surveyor named. The south slope was not given that name. Pricing the wrong pitch leaves the noted slope without a figure and dresses a different covering up as the repair. Read the note and the quotation onto the same side of the ridge.
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?
Nails need not fail on both pitches together. Exposure, the metal of the nail and the way that slope was laid can differ across the ridge. A visual survey that confines nail sickness to the north slope is drawing a boundary. It is not a hint to add the south quietly. If the south has a different defect, it will have its own sentence. Do not merge the two because both are parts of a roof.
Send the roofer the sentence that says north slope, and ask the written price to repeat those words. If the estimate talks about the south, the front, or a strip of every face, it is not yet the answer to this note. You may still ask them to look at the south. Label that as a separate look, not as the repair of the nail sickness already named.
What should you ask your surveyor?
- Which signs of nail sickness did you see, and were they only on the north slope?
- Did any slipped slate on the south slope receive a different description?
- What must a quotation say so that it is clearly about the named slope?
What are the typical next steps?
- Hand the roofer the north-slope sentence, not a request to price every face.
- Reject a south-slope total as the figure for this note.
- If the south slope is to be inspected, record that as a separate instruction.
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 nail sickness on the north slope set the life of the south slope?
No. The note names one slope. It does not give either covering a life in years, and it does not move the defect across the ridge.
Can one slipped slate stand for a re-roof of the house?
No. Even on the north slope, the note is the nail sickness described there. It does not condemn the south slope or the whole covering.