Damp patches are a common problem in the UK. One in five of our homes has issues with damp, condensation, and mould. If you've noticed unsightly damp patches on your ceiling, you are probably wondering where they have come from and what has caused them. You'll also want to know how to get rid of them and how to stop them from coming back. Read on for everything you need to know.
The key feature of a damp ceiling patch is discolouration. The patch can be in any size and can range in colour from grey to yellow or brown.
You might notice a damp or musty smell in the room, as well as bubbling or peeling paint or wallpaper.
In severe cases, there may be bowing or sagging in the ceiling itself.
Explore: Why Does My House Smell Musty
A damp patch can have a variety of causes. Before even thinking about how to remove, repair, and prevent dampness, you need to figure out where the moisture is coming from. Some causes of damp problems are an easy fix whereas others are an indication that something more serious has gone wrong.
Damp patches look unsightly and can create an unpleasant smell but that isn't where their problems end. They can also cause damage to the building and its occupants.
If damp is left untreated for too long, it can eventually interfere with the structural integrity of the property. Building materials such as brick, timber, steel, and more can start to disintegrate or decay. This is due to a build-up of moisture, mould, mildew, and corrosion of the materials.
There are also serious health risks associated with damp. The NHS advises that prolonged exposure to a damp home can cause health problems, including:
These problems are far more serious to the vulnerable. Babies and young children, elderly people, and those with pre-existing health problems are at more risk of becoming ill due to damp.
Excessive condensation is a leading cause of damp and wet patches. This problem happens when warm moist air hits cold surfaces. The moisture in the air cools down on the surface and forms water droplets. These water droplets collect and over time can build up into damp, mould, and mildew growth.
Condensation is a very common problem in the UK. We have one of the oldest housing stocks in Europe, with most of it being built before 1919 and around a fifth built before 1900.
Older houses are prone to damp and condensation, even if they are well maintained. This is due to the differences between older and modern building materials and approaches.
These homes, when they were built, were designed for their structural materials to be breathable. Made of stone, brick, lime plaster, and timber, moist air would escape through the walls themselves.
Over time, however, modifications and repairs will usually have been made to the buildings using more modern techniques and materials. Modern materials such as fibreglass, epoxy resin, cement, paints, and plastics completely interfere with the breathability of the building.
What this means is that excess moisture will build up within the house because it isn't able to escape as easily.
Explore further: How To Get Rid Of Condensation In Your Property
If the damp walls and ceilings are on the ground floor, then this suggests that the cause is a plumbing issue in the space above. It is impossible to tell from the damp patch itself what the problem is, but it is usually something like a leaking pipe or radiator.
Penetrating damp is caused by moisture infiltration from external sources. This is when something on the outside of the house is damaged and letting rainwater into the home.
If the damp patch is caused by penetrating damp, you may notice peeling paint and wallpaper alongside damp patches on the walls and ceilings. If the penetrating damp is coming from a roof leak, then the damp patches will be on the top floor of the house.
The penetration damp could be coming from:
Rising damp is a much less common issue than condensation and penetrating damp. It is when moisture from the ground rises up through the walls. Eventually, this moisture can get high enough to create a wet patch on the ceiling.
Common signs of rising damp will be damage to floorboards and skirting boards and plaster falling off the walls.
Rising damp usually suggests that a damp-proof course has failed or wasn't installed in the first place. The vast majority of houses will have a damp-proof course. It is a physical barrier that prevents moisture from rising up the walls of a building and can be in liquid form or a plastic membrane.
Poor drainage and poorly planned landscaping can also contribute to rising damp.
If you have a damp problem, you will want to get it fixed as quickly as possible. Thankfully, this can be done. But the method for fixing damp will depend on what is causing it in the first place. If you aren't sure, you can always call in a damp specialist to assess the root cause of the damp.
Rising damp can be fixed by installing a damp-proof course. This needs to be completed by professional builders and is quite a big job, but the problem must be fixed because rising damp can quickly lead to structural issues.
If the penetrating damp is caused by something like a leaking gutter or cracks in the wall, then there will be a fairly speedy fix. The work should be completed by professional builders who will be able to assess that the problem has been fixed and who can work on the outside of a building safely.
For roof leaks, the issue is usually cracked or broken roof tiles. This is a more specialist job but it is important to get a damaged roof fixed quickly because it can easily cause more extensive problems.
A professional plumber will be needed to deal with water leaks that have caused damp. They will be able to pinpoint the problem and replace any leaking pipes.
Condensation is one of the most common causes of damp spots. Many of the methods to reduce condensation are ones that you can tackle yourself but if you are frequently dealing with damp conditions, then you may need some professional help.
Condensation happens when there is excess moisture in the air that hits a cold surface and forms water droplets. Many of the activities you take part in at home will create moisture. This can include:
The other side of the coin is ventilation. With adequate ventilation, the majority of this moisture will be able to leave the building efficiently. If you have poor ventilation, however, the excess moisture can get trapped and lead to damp problems and, eventually, mildew and mould growth.
Take a look: What Causes Condensation On Walls
A positive input ventilation (PIV) system can help to improve ventilation throughout your home. It doesn't require extensive renovations in the same way that a mechanical ventilation system would.
A filtration unit is installed in your loft space with a distribution diffuser on the ceiling beneath. The filtration unit draws in fresh air from the outside which is then pumped out through the diffuser. This creates positive pressure throughout the home which forces the stale humid air out through naturally occurring ventilation spots such as window and door frames and other small holes.
A PIV system can reduce or even eliminate surface condensation. Moisture-laden air is constantly pushed out and replaced with fresh dry air. This means that there is no chance for water droplets to form on surfaces.
Discover: Are PIV Units Worth It
To reduce the moisture present in your home, you can change your behaviours. Reducing moisture is the easiest way to reduce your risk of condensation.
Methods include:
Lifestyle changes can only do so much to prevent moisture if the ventilation isn't adequate. Working to improve ventilation can make a big difference in reducing damp patches.
The first thing you will need to do is make sure that your extractor fans are working properly. Sometimes they can get blocked by a build-up of debris on the fan blades which will prevent them from extracting as much moisture as they should. Cleaning out this debris will help the fan to work more efficiently.
If your extractor fan isn't working at all and needs replacing, this is a job that should be completed by a professional.
A dehumidifier is designed to remove moisture from the air. Inside a dehumidifier unit is a refrigeration coil. The unit draws in the moisture-laden air, which is then cooled on the refrigeration unit. This causes it to form water droplets that are collected in the water collection bucket underneath.
This is quite a clever way of preventing this process from happening anywhere else in your home.
Before you take steps to remove a damp patch, you must figure out the underlying problems that have caused it. If you don't deal with the issues that are creating the damp patches, then they could lead to damage to the property or your health.
With that being said, damp patches look pretty awful so once the cause has been identified and fixed, you will want to get them removed as quickly as possible. Thankfully, this is fairly easy to do.
If the damp has got so bad that your ceiling is sagging or bowing then that section will need to be removed and replaced so it will be quite a big professional job.
If the damp patches are just cosmetic, however, then there are a few steps you can take to remove them.
If you have mould growth in your damp patch, then this will need to be removed. This can be done using a damp and mildew remover spray which you then need to wipe off with a kitchen towel.
It is important to always wear a mask when removing mould and mildew because the spores will escape into the air as it is being removed.
Don't try to remove mould using bleach. Bleach does not kill mould. It will only mask the problem. And the water in the bleach spray could even encourage further mould growth.
Dig deeper: How To Get Rid Of Mould Permanently
If the paint has blistered, you will need to scrape off the affected area. Then smooth out the rough edges using sandpaper.
Use stain blocker on the entire discoloured area. This will seal in the stain and prevent it from seeping through once you redecorate.
Once the stain blocker and the ceiling itself are completely dry, you can go in and start redecorating using ceiling paint. If the damp patches are especially dark, you may need to go over it with a few coats for it to disappear. Painting the entire ceiling is, of course, a good idea if you want to make sure that the colour matches.
Damp patches are a common issue on walls and ceilings. They are most often caused by excess condensation where warm moist air hits cold surfaces and forms water droplets. In some cases, however, they can be caused by a more serious structural problem such as a leaking roof, burst pipe, or rising damp. Depending on the cause of the damp patch, there are a variety of steps you can take to fix the problem and remove damp patches for good.
If a positive input ventilation (PIV) system seems like a good fit for your situation, you can get in touch with us at the PIV Team. We will work with you to ensure that your PIV system creates a healthier home with improved air quality and less risk of damp or condensation.
