Dealing with damp How much does it cost to repair damp?
Prices for dealing with damp
The cost to fix a damp problem will depend on the extent of the problem and where in the country you live. The table below gives approximate costs of what you can expect to pay for some typical damp solutions.
|Prices for dealing with damp|
|Problem||Solution||Terraced house - one wall||Terraced house - whole house||Semi-detached house - one wall||Semi-detached house - whole house||Detached house - one wall||Detached house - whole house|
|Ground level is above the existing damp proof course||Excavate soil only||£204||£268||£262||£594||£437||£1,456|
|Ground level is above the existing damp proof course||Excavate soil and lay pre-cast concrete paving slabs||£431||£728||£600||£1,491||£1,036||£3,274|
|No damp proof course in wall||Inject silicone damp-proofing course||£221||£350||£384||£769||£600||£1,899|
|Internal walls are damp||Asphalt tanking to 1.2m height and decorate to full height||£1,631||£3,250||£2,435||£6,477||£4,858||£15,3666|
These costs are from the Building Cost Information Service, which is part of the Royal Institute of Chartered Surveyors. The costs include everything necessary to carry out the work including labour, material and VAT (correct as of December 2011). For more information see our guide to tradespeople costs. You may also be interested in our review of gloss paint.
Which? members can find recommended builders, surveyors and damp-treatment companies on Which? Local.
Don't pay for unnecessary treatment
In our undercover damp-proofing investigation (published in Which? in January 2012) we found that households could be spending hundreds of pounds on unnecessary damp-proofing treatment.
If you are considering getting damp-proofing treatment done, you should make sure it is absolutely necessary by getting quotes from at least three companies and seeking advice from an independent damp specialist if there are inconsistencies in the work recommended.
In a snapshot assessment, Which? invited 11 damp-proofing companies to two houses with a total of three potential damp problems. These visits were then analysed by three damp-proofing experts, who found that in two thirds of cases the companies recommended unnecessary or inappropriate treatment, or missed the problem completely.
Five of the 11 damp companies that visited the first property recommended completely unnecessary treatment according to the experts – some costing as much as £1,440 – when they essentially should have suggested getting a plumber to fix a leak.
In the second property, only two of the 11 companies recommended a suitable solution for the penetrating damp problem in the hallway. Also in this property five companies failed to notice the likely damp penetration/rising damp problem at the front of the house. Of those that did identify it, only four recommended a suitable treatment.
Damp-proofing company scores
The overall scores for the biggest companies (how many occasions they gave good advice) were as follows:
- Peter Cox 2/3
- Rentokil 2/3
- Kenwood 1/3
- Lifecote 1/3
- ProTen 1/3
- Timberwise 0/3
Around half of the companies that visited the properties are members of the Property Care Association (PCA) - the largest trade body for the damp-proofing industry.
When Which? reported the most concerning findings to the PCA, it said it would undertake a full investigation and take appropriate action.