How to Identify the Type of Damp Affecting Your Home

Wed, Jan 15, 2025 12:10 CET

Damp is a serious and damaging issue that affects the appearance, structural integrity, and living conditions of your home. It’s not a problem that can be ignored as it will only worsen, potentially costing even more to rectify if not tackled immediately. But first, you need to know what type of damp you are dealing with.

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Below, property and construction expert Thomas Goodman at MyJobQuote.co.uk explains how you can identify each of the different types of damp in your home. Take a look at the list below…

What are the Different Types of Damp?

For most homeowners or renters, the most common types of damp encountered are:

Penetrating damp
Rising damp
Condensation related damp

Penetrating Damp

As the name suggests, penetrating damp is moisture which breaks through the protective envelope of your home. This could be via deteriorating mortar between brickwork, cracks in the render, broken roof tiles or rainwater from faulty guttering or downpipes seeping through the walls.

Rising Damp

Water that rises through the walls of your home in a capillary action is called rising damp for obvious reasons. Most homes have a protective damp-proof course, commonly abbreviated to DPC, which prevents this from happening. However, some very old properties may not have this protective barrier or it may have deteriorated or been compromised resulting in rising damp.

Condensation Related Damp

Perhaps the most common cause of damp in modern homes is condensation. This happens when moisture-laden warm air hits a cold surface, such as a wall, window, tiles, etc. Condensation is seen as water droplets on these surfaces. There are many causes of condensation but the major reasons are a lack of proper ventilation combined with a poorly heated property.

How to Identify the Different Kinds of Damp in Your Home

Knowing the different types of damp is helpful but you also need to know what the warning signs of damp are and where to look for them.

What to Look for and Where

Penetrating damp can happen anywhere around the envelope of the property. This could be through the roof, around windows and doors or through cracks in the walls.

Internally check around the walls, ceilings, door and window frames. The problem will present as wet patches on the walls or ceilings, usually with some discolouration or yellow/brown staining. There may also be some black mould, crumbling plaster or peeling wallpaper/paint.

Rising damp is potentially easier to spot as it will always be on the lower part of walls. It rises up from the ground and travels up the walls, often leaving an obvious 'tidemark'.

Salt deposits are seen on plaster and brickwork as they react with the moisture. Other signs to look out for are peeling paint and wallpaper, rotting skirting boards and sometimes, deteriorating floorboards.

Condensation-related dampness is caused by warm, moist air condensing on cold surfaces and remaining there. This produces damp and encourages the growth of mould.

Condensation will occur on any cold surface in the home, including the walls, windows and ceilings, when there is little or no ventilation. It's obvious by the presence of visible water droplets on these surfaces.

Fixing the Damp in Your Home

It’s important to fix the damp in your home before it causes problems with your health or that of your family, creates lasting damage to the décor or affects the structural integrity of your property.

Damp Survey

If the damp issue in your property doesn’t have an obvious cause, it is worth having a professional damp survey conducted. This type of survey assesses the extent of the damp, its causes and provides suggestions for the treatment and future prevention of the problem.

How to Deal with Penetrating Damp

Penetrating damp often has an obvious cause, you just have to find it. This means inspecting your property externally around the area where the damp is an issue inside.

Cracked render or mortar, leaking gutters or downpipes or broken roof tiles need to be repaired or replaced. Once the ingress of water is stopped, any internal damage can be repaired.

Resolving Rising Damp

Rising damp affects homes without a DPC or one which has been damaged or compromised. The latter can happen if the adjacent ground level is externally raised above the level of the DPC, allowing water to penetrate the barrier.

Fixing rising damp typically requires calling in a professional builder, although there are some products available for use on a DIY basis by injecting damp-proofing materials into the base of the wall.

Treating Condensation Related Damp

Damp caused by condensation is potentially the easiest to rectify. A change in lifestyle habits is often needed. You can also install some equipment, such as extractor fans, to improve ventilation or extra insulation to warm your home.

To tackle condensation related damp, you need to make sure your home is well insulated and properly heated. Adequate ventilation is essential, particularly when showering, cooking and drying clothes indoors. All of these activities add to the warm, moist air in your home, so removing as much of that as possible is key to dealing with this type of damp.

Preventing Damp Recurring

The way to prevent damp recurring is to identify, address and maintain the issues that lead to the damp in the first place.

To stop penetrating damp, keep the exterior of your home in good condition. Regularly check gutters, downpipes, roof tiles, and wall render for any damage and fix any issues promptly.

Addressing the cause of rising damp in your home by engaging a professional builder or using a treatment yourself and looking out for signs of it elsewhere in your home will help you prevent a recurrence.

Tackling condensation in the property by improving ventilation and maintaining a good interior temperature will alleviate any damp-related issues.

Adjusting certain living habits can also help, such as

opening a window or using an extractor fan while bathing or cooking
drying laundry in a warm room with the door closed and the window slightly open
using lids on saucepans when cooking

All these actions help to reduce condensation in your home and the potential for it to cause damp.

THOMAS GOODMAN

Thomas Goodman has worked as a property and construction expert for MyJobQuote for six years and has worked in the construction industry for over twenty years. Thomas continues to work on building projects while providing expert construction and property advice to industry professionals and DIY enthusiasts.

MyJobQuote is one of the UK's top trades matching sites that helps individuals find a reputable tradesperson in their local area.

MyJobQuote also has a wide range of experts with extensive knowledge in interior design, cleaning, gardening, property, construction and more. MyJobQuote's experts have been featured in over 700 publications, including Woman and Home, The Times, House Beautiful, BBC News and more.