5 Reasons, Why Walls Are Cold

If you feel the walls that are in contact with the outside on a cold day, chances are that the wall will be cold to the touch. This is pretty normal and the problem begins when the interior walls are also cold.

This is usually a sign that your house is poorly insulated. A poorly insulated house is not only uncomfortably chilly to stay in on a cold day but it is also pretty expensive because of the energy lost and the eventual repairs that will need to be made.

This article contains information about some of the reasons your walls are cold together with a couple of helpful solutions that you might need for your repairs.

Reasons why the walls are cold

Like I said earlier, the main reason why your wall is cold is that you have a problem with your insulation. This results in a wall that quickly allows warm air to leave the room and go outside or into another room. Walls with poor insulation also allow cold air to travel from the outside into other rooms of the house.

Here are some of the detailed causes of cold spots in your house walls together with their solutions:

1. Dirty and rusted wall ties


Wall ties are inserted between the two walls of a cavity wall to bind them to each other and allow them to support each other. When the wall is being built, some mortar falls on the wall ties that are inside the cavity. With time, the mortar picks up dust and some moisture. The mortar also allows this moisture to come into contact with the internal cavity wall. the route it creates for the moisture in the wall is called a cold bridge.

The result is a spot on the wall that has a lower temperature than the rest of the wall, called a cold spot.

If these wall ties are exposed to moisture and water over a long time, they will start to rust and this will cause them to expand with time. As this happens. The mortar around the wall tie will begin to disintegrate, forming a gap in the external wall. Moisture and cold air can travel through this gap and make their way into the inner cavity walls and form a cold spot in the walls.


You will need to locate the wall tie that is causing the problem and fix it. To make this easier, you can use a metal detector around the cold area to find it. As soon as you have identified the culprit, remove at most two bricks so that you can inspect the area.

If the root cause is a dirty wall tie, clean it thoroughly to get rid of the dust and mortar around it.

For rusty wall ties, you will have to replace them. This will fix the problem and ensure the wall’s structural integrity is maintained. You can do this yourself or seek the help of a professional. If you decide to do it yourself, ensure that you know enough about them so that you do not cause damage.

2. Poorly-done insulation


Another highly likely reason why your house walls are cold is that the cavity insulation was not properly done. There are a couple of things to consider when it comes to doing this for example the type of insulation to use and the proper tools to perform certain procedures. 

If a cavity wall is constructed poorly, there will be holes containing air in the filling and these will result in a difference in temperatures at various parts of the walls, forming some cold spots.


You will also have to take out a couple of bricks so that you can see if insulation is the culprit. If it is so, you will see air spaces in the insulation. The only way you can move past this is by getting the installation redone. 

When you do this, ensure that you look for a professional who knows their work well. Do proper research on the different cavity insulation companies in your area and identify a credible one to work with. They should also perform a survey of the walls to determine what materials, tools, and techniques to use on your property. 

It is also in your best interests to work with a company that will give you insurance on their services and their materials. This way, if there is another unfortunate incident, you will not have to pay for repairs out of pocket.

3. Penetrating dampness


This is what happens when moisture passes through a layer of the wall and starts to compromise the surfaces behind it. This is common in brick walls and it happens as a result of the bricks on the outside wall cracking and allowing water to pass through them. 

Damp walls are colder than their dry counterparts because they tend to lose heat about three times faster.

In some cases, the water dilutes with salts in the brickwork and they are drawn out to the surface of the wall when the water evaporates. These salts split the plaster and give you another expense. In addition to the cold walls, you might also suffer from a damaged pointing mortar.


You will need to take out the cracked and crumbling bricks and replace them. This process is pretty easy but if you find yourself replacing more than two bricks, you should consult a professional.

4. Cracked renders


Cracks in the render of any facing can also cause cold walls. It does this by allowing water to leak through and this forms damp patches on your walls. A render can crack for various reasons but the most common is a poorly applied scratch coat. This is the first coat of plaster that is applied. If this scratch coat does not have a similar consistency to the topcoat, it might crack. Poor weather conditions at the time of installation can also cause cracks in the render.


If you are looking for an affordable answer to your problem, you could use filler to repair the crack in the render and then seal the join. A disadvantage of this method is that this repair will be visible even if you paint over it.

Another option is to take apart the whole render and do it anew. If you do this, ensure that the surface is cleaned and well-prepared for rendering. This is done by removing any paint and setting a layer of bonding slurry. You should also ensure the consistencies of the coats are even.

To prevent the problem from arising again, you should do some practice renders before you move to the wall so that everything is perfect. You can also hire a professional plasterer. However, this is an expensive procedure but you might have to bear the costs. 

5. Pipes and fixings in the wall


When a building is being constructed, the plans may suggest that some pipes run within the cavities of the wall. These pipes are usually placed there for the convenience of the central heating system.

Sometimes, the electrician may also decide to pass some wiring through the wall for lighting components like bulbs and switches. There are also some fixings like bolts and screws in the walls. These can sometimes penetrate through the cavity.

If there is a leak in the rooftop or if there is any way for water to get into the cavity, the water will flow along the voids caused by attaching fixings. This will result in cold points on your wall and dampness may also occur. 


You will need to determine whether it is a pipe, a circuit, or a wall fixing that is causing the issue. To do this, you should take out a brick on the outer side of the wall. 

Once you find the problematic fixture, you should take it out of the wall if it is removable and using a solid filler, properly fill the hole and restore the object.

Other fixtures like heating pipes cannot be removed. You will have to use a flexible filler to ensure that the void around it is filled well.

If fixtures are the cause of cold walls, it is also a clear sign that you have a leak in your house. You should make arrangements with a plumber to identify the source of the leak, its causes, and how to fix it.

Final thoughts

Cold walls can make your house uncomfortable, especially in the cold season. There are a couple of reasons why walls get cold but luckily, there are ways of fixing these problems. 

If you notice your walls getting colder, you should find the root cause as soon as you can to prevent the extensive damage that they bring if they are not repaired early. You will also save some money on your heating bills and repairs.

You should also remember that if you are feeling unsure about doing any of the procedures, please contact a professional to make the repairs.

Melanie Asiba

Melanie is an author, and she enjoys traveling, reading, and trying out new things. In addition to writing for Apartment ABC.

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