No one wants to find out that they have damp in their home or business. Whether you’re a homeowner or a renter, damp can truly spoil your living space and make your home feel squalid and unhealthy. Damp can kickstart or exacerbate health issues and devalue the price of your property. At its worst, damp can signal that you have structural and weatherproofing issues that can be costly to fix.[1]
Many new homes are built with damp-proofing measures in place, but older homes and buildings are susceptible to this problem. While you might think you need to run to the phone and book a professional to come and deal with the problem, in most cases damp can be dealt with on your own. Read our thorough guide on how to identify and deal with your damp problem.
What Causes Damp?
Damp is a signal that there is a build-up of moisture that can’t escape.[2] simply an excess of moisture that can’t escape. All houses contain a certain amount of moisture that is present in the building materials and is hanging in the air. Moisture is naturally drawn to drier areas and tends to travel downwards.
That said, damp is caused by an excess of this moisture, which is caused by one of two factors:
- A sudden increase in the moisture in your building
- A gradual accumulation of moisture that cannot escape
Here are some of the most obvious causes of damp:
- Leaky plumbing – Drips of water escaping from your plumbing can wreak havoc on your home. The drip might seem tiny, but over time it can cause a large damp patch. Look out for corroded pipes hidden in walls, new plumbing fixtures that could be leaking, hairline cracks in bathroom grouting, faltering waste pipes, and damaged seals around your fixtures.
- Leaky Gutters – Leaking gutters can cause water to spill down your external walls or splatter onto your pavements. Over time, it can soak down into the foundations of your home, or sneak into your windows.
- A hole (or holes) in your roof – If your home has broken or missing tiles, worn thatch, or slipped slate, water can sneak down into your home.
- Small Gutters – Are your gutters large enough for your home? If the climate has changed or you have increased the area of the roof since the house was first built, your gutters may not be able to handle the rainfall. Look out for water splashing out over the edges of your gutters.
- Blocked windowsill grooves – Most houses are equipped with windowsills that have external grooves that help the water drain away from the window. If these grooves become blocked, the water will end up running directly down the wall under the window.
- High humidity – If you have high humidity in your home, you should get rid of it as soon as possible with extractor fans, venting tumble driers, and trickle vents on your window.
- Condensation on windows and walls – Condensation causes patches of damp and speckled black mould on your walls, and is often caused by leaky pipes. You’ll often see it appear near sinks and toilets, or on the ceiling in bathrooms and kitchens.
Identifying the type of damp you have
There are three main types of damp that might be affecting your home.[3]
- Condensation – Condensation is often considered the most common type of damp. As warm moisture condenses on the cool walls, floors, ceiling, and tiles, it can leave damage and mould behind. It occurs most often in the winter, as the heated indoor air lands on cold surfaces, and there are fewer windows left open. To identify condensation, look for water droplets on your windows, black mould, and a musty smell.
- Rising damp – Rising damp occurs when ground water moves up a wall. In newer homes, damp-proof courses or membranes (strips made of plastic or bitumen felt installed into the wall). You can recognise rising damp when you see damaged skirting boards and plaster, peeling paint, damaged wallpaper, and white ‘powder’ tracks left on the wall (left by dissolved salt in the water).
- Penetrating damp – Penetrating damp occurs when water leaks through walls horizontally, rather than travelling upwards. This usually occurs due to structural problems, including issues with the gutters, roof, or cracks in the wall. You can recognise it by damp patches on your ceilings and walls which get darker when it rains.
How to Get Rid of and Prevent Damp
It’s easier to prevent damp that it is to treat it once it has become a problem.[4] Here are some ways to prevent damp before it starts, and how to remove it once it moves in.
1. Wipe down your windows every day
As soon as you see condensation start to build on your windows, wipe it down with a towel or a squeegee. To move mould once it has bloomed, wipe it away with a warm soapy cloth, and then use a new cloth to completely dry the area. It is important that you then throw both cloths away.
2. Don’t let steam billow when cooking
When you’re cooking, place a lid on your pots and pans so that steam doesn’t billow out into your kitchen and beyond. You should also install an extractor fan in your kitchen and look into ways that you can heat your kitchen in the winter to dry moisture faster, preventing it from seeping in.
3. Watch out for bathroom moisture
When you’re showering or running the bath, lots of steam will float around the room. Shut the door to prevent this steam from entering the rest of your home, and always leave the fan on when the taps are running.
4. Improve your ventilation
You should open the windows in your home for at least 15 minutes each day to let damp air outside and bring fresh air indoors. You should do this even when the weather is cold outside. You can also install a plastic air brick that will allow lots of air to flow into your floorboards.
5. Make sure your home is warm enough
If you don’t keep your home warm enough, the damp will be a bigger problem. Keep your home heated to a steady temperature by setting timers for your heating system to come on at regular intervals throughout the day. Installing underfloor heating is a good way to keep your home cosy and warm throughout the colder months. With an underfloor heating kit, it’s easier than you think to install.
6. Ensure you have strong insulation
Good insulation will keep your home toasty and warm, prevent the accumulation of damp, and save you money on your heating bills. Double or triple glazed windows will also help keep your home well-insulated.
7. Place a dehumidifier in damp rooms
Dehumidifiers reduce the amount of humidity in enclosed spaces by sucking air in and then removing the moisture, and then blowing it back into the room.
8. Hang your clothes to dry outside
Whenever possible, hang your clothes outside to dry outdoors rather than in your home. A tumble dryer (well-ventilated, of course) is the best solution, as it prevents damp garments from hanging around. If you do need to hang your clothes inside, place a dehumidifier next to the rack.
How to treat damp walls before painting
If your walls are damp, you’ll need to treat them before you start painting. Of course, you shouldn’t even start this process until you have determined the source of the damp and you have treated it.[5] If you need to remove mould, you should use a warm soapy cloth, and then blot dry with a different cloth. Throw both cloths away immediately so that the spores do not spread.
Once the damp has been treated and the walls are completely dry, you should select an anti-damp paint, which can be purchased from home shops and large home maintenance stores.
If you must paint over a damp wall, you will need to use a chlorinated rubber paint. As long as you have dealt with the source of the leak, the rubberised paint should deal with the damp for good. Once you have applied the paint, you need to let it dry for 20 minutes before you can add standard paint to the wall.
How Much Does Damp Proofing Cost?
Of course, the cost of damp proofing your internal walls will depend on the dimensions of your room, and the extent of any previous damage. If you need to damp-proof an internal wall, a lot of the cost is incurred from the plastering and redecoration process that takes place afterwards.[6]
A rough estimate is that it will cost between £70 per metre of wall being treated. The costs can rise up to thousands of pounds if you need to treat your entire home.
For your external walls, you will likely have to lower the ground outside by digging out a trench of earth and covering it with concrete or gravel. This cost for this will depend on the size of your home, and the price of the materials that you choose. To dig the soil around a small home and lay down gravel, you might only pay £400 – £500. However, to lay down a concrete path it could cost as much as £2,000 for a small home, and much more for larger buildings.
Damp can truly ruin your home, making it uncomfortable and causing serious damage over time. Try to prevent the problem before it becomes a big issue.
Reference list
Cutmore, A. (2019). How to get rid of damp, condensation and mould. [online] https://www.idealhome.co.uk/diy-and-decorating/how-to-get-rid-of-damp-185033. Available at: https://www.idealhome.co.uk/diy-and-decorating/how-to-get-rid-of-damp-185033 [Accessed 15 May 2020].
DIY.com (n.d.). Dealing with damp. [online] DIY. Available at: https://www.diy.com/ideas-advice/dealing-with-damp/CC_npcart_400241.art [Accessed 15 May 2020].
Evans Decor (2016). How To Treat Damp Walls Before Painting. [online] Evans Decor. Available at: https://www.evansdecor.com/treat-damp-walls/ [Accessed 15 May 2020].
Kinsey, D. (2017). Causes of damp. [online] Homebuilding.co.uk. Available at: https://www.homebuilding.co.uk/causes-of-damp/ [Accessed 15 May 2020].
My Builder (2020). How much does damp proofing cost? [online] My Builder. Available at: https://www.mybuilder.com/pricing-guides/damp-proofing-costs [Accessed 15 May 2020].
Ransome -Croker, L. (2018). What kind of damp is affecting my home? [online] Which. Available at: https://www.which.co.uk/reviews/damp/article/dealing-with-damp/what-kind-of-damp-is-affecting-my-home [Accessed 15 May 2020].
Resources
[1] https://www.diy.com/ideas-advice/dealing-with-damp/CC_npcart_400241.art
[2] https://www.homebuilding.co.uk/causes-of-damp/
[3] https://www.which.co.uk/reviews/damp/article/dealing-with-damp/what-kind-of-damp-is-affecting-my-home
[4] https://www.idealhome.co.uk/diy-and-decorating/how-to-get-rid-of-damp-185033
[5] https://www.evansdecor.com/treat-damp-walls/
[6] https://www.mybuilder.com/pricing-guides/damp-proofing-costs
