Condensation running down a window

How To Stop Condensation in a Flat

21 September 2023

We often talk about how condensation effects a property on this site, and there are plenty of different pages looking at how condensation can spread in a detached, terraced, or semi detached property.

What about a flat though? Specifically, one situated one or more floors above ground level?

Well, hopefully this blog will give you some idea of what might cause high levels of condensation in a flat above ground level, and how you can stop that condensation from spreading further through your flat.

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Why is My Flat Damp?

Signs of damp on internal wall in house

There are plenty of different causes of damp, and its important to understand the differences between them if you want to learn if condensation is actually the main cause of damp in your flat.

First, there is condensation. Condensation is a form of damp caused primarily by day to day living and a lack of adequate ventilation. Condensation is one of the leading causes of damp in the UK, and is actually one of the biggest contributors to black mould growth in UK properties. Condensation can happen anywhere, but with condensation being a problem in spaces where there is a notable lack of ventilation, condensation can always be a little more prevalent in flats.

Second is penetrating damp. Penetrating damp is the fault of something within the buildings construction failing. This might be bad pointing, ruined gutters or drains, a leaky pipe – anything that is allowing moisture ingress in a location where there should be none.

Then, there is rising damp. Rising damp is the process of moisture travelling upwards from the ground into a properties walls via a process called capillary action. Capillary action sees moisture slowly rise upwards into a wall, travelling generally as high as around a meter above ground level.

Rising damp occurs mainly in properties built without a functioning DPC (damp proof course), or in properties where the damp proof course has failed.

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Why Is Damp in a Flat Different from a House?

Damp and mould on internal wall in house

As mentioned in the last section, the different types of damp are categorised due to their cause. Rising damp, as a result, may be the least likely type of damp to appear in any flat located above ground level because capillary action will rarely travel that high.

So, one answer to why damp is different in a flat to in a house is because of the cause of the damp itself – its much less likely that a failed or missing DPC will be to blame.

This leaves two separate options as a cause for the damp. The first is penetrating damp.

Penetrating damp, as mentioned before, is down to a failure in a properties building materials, the drains, the pipes – anything that allows moisture where it shouldn’t.

The easiest way to get rid of penetrating damp is to identify its source, and then fix it. However, this may well be easier said than done in flats. For example, let’s say that the bathroom of a flat is having a consistent problem with damp showing up in the ceiling.

It might well be that the owners of the flat experiencing the damp problem are doing nothing wrong at all. In fact, it might be that the flat above has a leaking pipe, a shower that doesn’t contain water as it should, or even just a tenant or owner with a tendency to take baths that splash everywhere, every night.

Any of these, and potentially hundreds others, could be the reason that moisture is consistently sinking down into the floor and causing damp to appear in your flats ceiling. Sadly, this isn’t a fix you can immediately jump on and sort yourself, or even via a plumber or builder as the question of ownership and responsibility comes into play.

Essentially, there are many reasons that you might discover penetrating damp in a flat, but there is only so much within your power to solve if the damp is caused by a neighbour, or a facet of the building owned or managed by a third party.

Then there is condensation.

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Need Help With Condensation? Call 0800 288 8660

Condensation in Flats

Black spot mould forming from condensation on interior wall

Condensation is one of the biggest causes of damp in flats in the UK.

Many are told that condensation is a consequence of lifestyle – and to an extent this is true. Condensation is created when any action that creates warm, moist air takes place. A shower, a bath, cooking, drying clothes – even indoor exercise can result in the creation of condensation.

In fact, one of the most surefire ways to reduce the level of condensation in a flat is to be mindful of the condensation that your actions create. Putting lids on your pots, taking shorter or cooler showers, drying your washing outside (if possible) or off site are all ways you can make sure that less condensation is created, lessening your damp problem.

However, what can often make things worse is a distinct lack of ventilation. Ventilation can be achieved in all kinds of ways, but they may often be more difficult in a flat simply because of how they are constructed and owned.

Let’s start with the most practical ventilation solution: an open window. Often in a house, opening a window wide is going to create an immediate ventilation option, and it can be made even more effective if all the doors and windows in the rooms adjoining are opened too, creating a through-draft.

It is often the case though that in high rise flats windows are much more difficult to open due to safety regulations, and you might not be able to achieve the same level of ventilation that you might in a house. This is just one option though, and there are plenty of others available if you are looking to increase the level of ventilation in a flat.

For example, extractor fans. Extractor fans are a great way of channelling the excess warm air created during, for example, a shower, and venting it outside. Or, they can work in a kitchen to capture and release the steam created when cooking outside, where it won’t cause any further damp.

Another method of reducing condensation in a living space is a positive pressure system. These are systems that act to constantly introduce a constant, low pressure flow of air throughout a living space that works to encourage any warm air that has been created out of ventilation points within the property.

Whilst these are primarily solutions for properties like houses, they can be installed within flats if the conditions allow.

Sadly, in many instances it might be more difficult for those living in flats to get different ventilation options fitted if they aren’t already featured. In many cases flats are rented, or as the owner of a flat you will have to get permission from a buildings management to add any modifications or extras.

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Need Help With Condensation? Call 0800 288 8660

How to Install Ventilation in a Flat

In the instance that the flat belongs to you, and you are totally at liberty to install whatever modifications you might want, then it best you contact an expert to identify not just the source of the condensation being created, but also to install whatever ventilation options you might need to control condensation more effectively.

For example, trickle vents in a window may be difficult to put in for the layman, and an extractor fan might need a professionals touch – especially if you are several floors above ground level.

Of course, this becomes a little more difficult when the flat doesn’t belong to you, Or is subject to management. What you will need to do in this situation is talk to your landlord or management company about what steps they are willing to take, or allow you to take, to reduce the level of condensation in your flat.

Remember, a long term solution that minimises the spread and longevity of damp is the best result for everyone involved in this situation, and approaching your landlord or building manager with a reasonable request is always in your best interests.

If you are looking for professionally researched backing on how to reduce damp in your flat, a way to install a new positive pressure system, or you just want an expert to help identify what it is creating the condensation in the first place, you can always request a survey from Timberwise.

We will always carry out a thorough, independent and totally unbiased survey that will provide you with not just answers on how and why condensation is being created in your flat, but also a report that will outline the next steps you, or the property owner or manager can take to reduce condensation building up in the long term.

For more information you can request a survey online below, read more on our condensation survey process here, or just have a chat with our team by calling 0800 288 8660.