What are the different types of damp?

Damp is a silent, but deadly, condition which can wreak havoc in your workplace. Once spotted, it is vital that you embark on a course of treatments straight away to get this pest under control from day one. Not getting the upper hand can lead to spreading and an even more severe issue later down the line.

Obviously, dampness can lead to mould and other hazards to your employees’ health. So it is important to keep on top of it at all times to maintain optimum conditions. Being able to spot the different types of damp in your workplace if the first step towards this. Read on to find out more about the different types of damp in the workplace, as well as how to spot the signs and treat the problem before it gets worse.

What are the main causes of damp?

With the UK’s frequent downpours, homeowners and businesses alike often encounter issues of mould and damp, particularly in the lead-up to winter. This can play a major role in your air quality and health. The common causes of damp, in a nutshell are:

• Discoloured walls
• Cold surfaces
• Black marks in corners of windows and areas with sealant

The common culprits behind these problems are penetrating damp, leaking pipes, condensation build-up, and high humidity resulting from daily activities like cooking and washing. If you notice brown marks on your ceilings and around damaged chimney breasts, this signifies penetrating damp (whilst noticeable wet patches may indicate leaking pipes).

Types of damp

1. Condensation

This is often the biggest cause of damp – both at home and in the workplace – it is also something which you can deal with quite easily. Signs of condensation are straightforward; steamed-up windows, puddles, damp patches, water running down walls, mildew patches and peeling paper or paint on your walls.

In the home, condensation obviously builds up in badly ventilated kitchens and bathrooms. But, this is also a danger in the workplace. Especially in steam treatment rooms in some types of factories. Condensation can also build up under your floorboards, where it is trapped, and cause dry rot. So it both a problem for the domestic and commercial sectors.

How to treat condensation

Ventilation and well-heated rooms during all seasons is key. Modern houses often have ‘trickle vents’ installed at the top of their windows, allowing for a small amount of background ventilation. Extractor fans in kitchens and bathrooms can also provide significant aid in reducing moisture level.

Maintaining a consistent indoor temperature can help prevent condensation damp. For instance, during winter, keeping your heating at a consistent temperature, such as 18°C during the day and 15°C at night, can reduce the likelihood of condensation. If you utilise ductwork in your commercial building (particularly in an environment prone to damp), then commissioning stainless steel ducting can help prevent damp and mould from occurring. 

When it comes to reducing condensation around windows, bathrooms and rooms where dampness is likely to occur:

• Turn on your extractor fans
• Open your windows regularly (yes, even during the colder months)
• Wipe down your windows and window sills
• Have cooler showers
• Hang damp towels and clothes outdoors if you can

2. Rising damp

This is a form of damp which is not always obvious at first, especially as it can develop more under the floor than above it. Signs of rising damp include:

• Staining on walls
• Peeling or blistering paintwork
• Tide marks on walls
• Damage to skirting boards
• Foul/musty odour

If you notice these signs, it’s important to consult with an RICS registered chartered building surveyor to establish the cause of the damp and find a suitable solution. Although it can sometimes be seen rising up walls if it is allowed to get to a worse state. Luckily, you can often smell damp even if you can’t see it and so you should have ample warning before any damage to brick, concrete or wood occurs.

How to treat rising damp

Rising damp is a more complicated issue to treat than most damp. You will need to have a damp-proof course either installed or replaced, so you will need professional advice on this matter. Typically, treatment for rising damp may involve repairing the existing damp proof courses, installing new ones, or increasing the ventilation within the home. 

It’s worth checking whether your property has a damp proof course and membrane installed – as well as when it was installed and what condition it’s in. For homes, the level of garden soil directly next to the house should not rise higher than the level of the damp-proof barriers.

3. Penetrating damp

Blotchy patches on the wall and large spots of damp are typical indicators of this, as well as wet or crumbling walls, fungus or mildew, and in more severe cases water found on the surface. This can occur due to a number of reasons: missing roof segments, badly fitted windows or doors, faulty roofs and bad wall flashing.

How to treat penetrating damp

Preventing penetrating damp involves regularly checking roof space for any signs of water intrusion or damp timbers, ensuring that air bricks and other ventilation/moisture preventing devices are not obstructed, and maintaining the exterior pointing and paintwork.

Regular repair and maintenance of the outside of your home should remove this an issue. So long as damp cannot penetrate your business premises due to an external issue, then you should be safe from penetrating damp. If some damp does penetrate, then use a space heater to keep the areas as dry as possible whilst the external issue is fixed.

4. Leakage

Leaks that are obvious can be quickly spotted and dealt with in the workplace. But, small and unnoticeable leaks can slowly grow over time and cause damp problems. Drips, puddles or patches of water where they shouldn’t need to be watched for in order to ensure no hidden leaks exist.

This could be a result of cracks in pipework, ageing rubber on pipework bindings, bad tiling or even porous grout. If you have a wet area in your workplace, then always check the sealings of the space or room regularly to avoid these small but damaging leaks.

How to treat damp caused by leaks

The cause of the leak needs to be found and dealt with. Always be on the lookout for any problems and ensure that all of your sealants are as effective as possible. If a problem does occur, then fix it as soon as humanly possible.

Start by finding where the water is coming from (like a broken pipe, damaged roof, or a malfunctioning appliance). Once you’ve pinpointed the source, get it fixed right away. If you leave it, the problem might get worse. Ensure the affected area is completely dry once your leak is fixed using dehumidifiers to prevent mould growth.

If anything in the area has been soaked, like carpets or wallpapers, take them out. They could make the damp worse and might even get mouldy – so replace them as soon as you can.

Frequently asked questions about damp in the workplace

What are the four main types of damp?

The four most common types of damp include:

• Rising damp
• Penetrating damp
• Damp caused by defective plumbing or leaks
• Damp caused by condensation

Can you get damp on internal walls?

Yes. The main reason your indoor walls get damp is because they don’t have a proper waterproof layer called a damp proof course, or it’s not working well enough. This layer stops water and moisture from coming up your walls.

Sometimes, the lower part of walls can get damp because water from the ground slowly moves up through the walls. People often put in something to stop the wetness, but it might not stop water from getting in from the sides. If you don’t fix this in time, it can damage the bricks and wood in your walls.

Does bubbling paint mean damp?

Also known as paint blistering – bubbles in your paint can be a tell-tale sign of damp present in the area. This is common in steamy rooms like bathrooms or kitchens.

How much does it cost to fix damp?

Fixing damp can vary in costs due to their location, severity, cause or all three. Prices can start from £1,000 and rise to around £10,000 (again, depending on how severe the problem is). Obviously, this is just an estimate, but something to consider before you let a damp problem progress.

How do you check for moisture in walls?

Moisture within and behind walls can be detected with a pinless moisture metre, as well as simply looking at the wall, or hiring a professional inspector to use thermal imaging. A non-destructive moisture metre can accurately locate and measure elevated moisture levels without the need to break the wall’s surface material.

How do you tell if there is a leak behind a wall?

Besides musty smells and visual signs on your wall, here are some other ways to tell if there is a leak behind your wall:

• There are puddles of water in the area
• Water is dripping behind the wall or ceiling
• The texture of the wall or ceiling looks different (it may have “bubbles” or “blisters”)
• The walls or ceiling looks discoloured

Of course, not all of these are preventable. No one can predict a leaking pipe, after all. But you can prevent most of these issues by having good air quality in your work environment. Which comes from having a comprehensive fabrication and/or ventilation system installed in order to ensure you have the best working conditions possible.