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Don’t pay thousands for damp-proofing treatments you don’t need

Damp treatments can cost as much as £15,000

Damp by double glazed window

Damp treatments can cost anything from £100 to as much as £15,000.

Damp problems are infuriating and can cost anything from around £100 to as much as £15,000 to fix. But you don’t necessarily have to spend a fortune to sort out your home’s damp issues. 

Damp can be caused, or exasperated, by an array of things. But if you know what you’re dealing with and how much it could cost, this will help you avoid costly work that might not be needed. 

We’ve worked with the Royal Institution of Chartered Surveyors (RICS) to get the average cost of dozens of damp-proofing jobs. You can use our research so you know what to expect and don’t get ripped off. 

For estimates on everything, from repairing a damp-proof course to sealing floors from damp, go to damp repair costs.

Identifying and fixing damp yourself

We recommend trying to identify the issue yourself before calling in the professionals – the more information you’re armed with, the less likely you are to pay out for unnecessary work.

Investigate where the damp might be originating from, as this could uncover a simple and cheap solution. 

  • Check whether there is a leaking pipe that you could replace.
  • Fill any cracks or breaks in the external walls, particularly around windows and doors.
  • Clear blocked gutters and fix broken soffits.
  • Repair any damage to your roof that’s letting in water.
  • Ensure the ground level outside is 15cm below the damp-proof course (DPC), or water will splash above it. 

Also, think about whether there is enough ventilation in the room where the damp is. This is particularly important if your home is old, as new insulation or windows can reduce vital ventilation. 

Our comprehensive guide to rising damp, condensation and penetrating damp will talk you through all the possible causes, as well as show you ways to rid your home of damp.

Damp proofing treatments

There are other potential causes of damp that are less easy to repair yourself.

Damaged or non-existent damp-proof courses or membranes may need professional attention. A damp-proof course is the thin strip running horizontally through the brickwork mortar joint near ground level of your home, and a membrane sits below the floor. You may be able to rectify issues with damp coming through the damp-proof membrane by painting underneath the floor-covering with latex waterproof emulsion.

It’s possible that damp is being caused by cavity walls becoming blocked. Alternatively, if you have any cavity trays (these help to stop water reaching the inside wall), they could be faulty.

If you think you’ll need professional help to rid your home of damp, make sure you get a few opinions and quotes. Then you can feel confident about the recommendation and the price you’ll pay. You can use find a trustworthy, local damp-proofing service by using Which? Trusted Traders.

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