It's a stone cottage built in 1816. One wall of the house is below pavement level, and that's where dampness is creeping in. We reckon a trench dug between the wall and the pavement would be a lot better and allow the house to deal with dampness as it has done for the last 200 years. Surveyor is sticking to his guns (odd that, seeing as he works for a chemical damp proof treatment company) and his report needs to go to the mortgage company for final agreement.
It's not a cost-thing, as it's roughly the same to get a trench & proper drainage dug in. I've just seen lots of photos of damage to old buildings where a chemical damp proof treatment has locked the water in to a wall it would otherwise have evaporated from, and I don't want that happening to my house.
What options do we have?