As properties age there are certain areas of the building that suffer from wear and tear. This includes construction materials that deteriorate over time.
A few examples include things like the roof, window, and door frames, and brickwork and pointing.
When any of these areas start to form defects, they become a potential risk for penetrating damp. This is a process where water enters the property through small gaps and cracks. Once this starts to happen it can quickly lead to internal damp issues.
Poor pointing is a very common cause of penetrating damp. Pointing is usually softer than the bricks it surrounds. This means over time it will deteriorate and need replacing.
If pointing is not replaced, or if it is repaired poorly, water could start to penetrate your property and cause damage internally.
Will repointing solve the problem?
If poor pointing is the cause of your damp problems, then replacing it will solve this issue. However, it is worth noting, if the new pointing is installed poorly, this can also result in future problems.
For smaller jobs you may be able to do the pointing yourself. There are plenty of video tutorials online, that can help you quickly patch up a small amount of damaged pointing.
But, when it comes to bigger jobs, such as repointing an entire house, it is usually worth hiring a professional builder.
How to patch a small area yourself
If there is only a small area of pointing that needs replacing, you may decide to do the job yourself. To get started you will first need to prepare the surface and remove any old pointing.
It is recommended that you scratch out the old pointing to around 15mm. This will allow plenty of depth for the new mortar to grip into the joint.
To remove the old mortar, you can use a hammer and chisel, or a mortar rake. You could also use a grinder with a special bit attached (a raking bit) to dig out the old mortar.
The difficulty of this part of the job will depend on a couple of different things:
- Is the old mortar a lime or cement mix? A lime mix will often be found in older period properties and tends to be quite a bit softer than cement.
- How badly has the pointing already eroded? If the existing pointing is in bad shape, it may be quite easy to reach a depth of 15mm.
Once you have scratched out the mortar to an acceptable depth, you can clean the surface and remove any dust and debris. This can be followed by spraying the area down with clean water.
Once dry you are now ready to apply the new mortar.
Should you use lime or cement?
As a rule of thumb, you should replace the old pointing like for like. This means if the original pointing was done with a lime based mortar, then you should replace it with the same.
There are a few ways you can try to identify if the existing mortar is lime.
- The age of the property. If your property is older, for example a Victorian terrace, then there is a good chance the pointing will be lime mortar. Especially if it is the original pointing.
- Was it quite soft and easy to scrape out? Lime tends to be softer than cement.
- Check the colour. This can be quite subtle, but cement based mortars tend to have a greyer colour. Whereas lime is usually more white.
- Check for small white spots in the mortar. Sometimes in lime you will find small calcium deposits.
- Try spraying the surface with white vinegar. The acid in vinegar will react with the lime causing it to fizz slightly. This will work particularly well on white calcium deposit spots.
In all honesty, this is quite a tough one to identify. Most of the differences are very subtle and may not be easily identified by the untrained eye.
If you are unsure, then this could be time to seek the advice of a professional builder.
Applying the new pointing
Once you have decided on the type of mortar you will be using, you can start to mix your sand and cement/lime and get started.
You will also need to try and colour match your new pointing, with the existing pointing. This can be difficult if you are not a professional, with some level of experience. However, there are guides online that can assist in this process. Like this one by DIY doctor.
Essentially there are a few ways you can affect the colour which can be seen below:
- The sand to cement ratio.
- Type of sand that is used
- You can also use dyes that adjust the colour of your mix.
Once you have reached a colour you are happy with, you can start to apply the new pointing.
There are various methods of applying pointing. Some people will use a standard pointing trowel and others will prefer something like a finger pointing trowel.
Below is a great example video of somebody pointing with a finger pointing trowel. He also happens to be using a lime mortar:
Remember poor re pointing can also cause damp
The most important thing to remember, is that a shoddy job, will likely cause more problems than it solves.
If you are unsure about doing the pointing yourself, just bite the bullet and hire a pro to do the work.
If your property is suffering with damp due to poor pointing, a bodged job could make the water ingress even worse.
You really need to weigh up the pros and cons of having a professional in to do the work.
Obviously, there is a cost attached to hiring a professional trades person. However, you should also consider the damage and potential cost caused by penetrating damp.
In the long term damp can cause damage to internal decorations and plaster. This will almost always lead to mould growth, which can quickly spread to different areas of your property.
There are also more serious problems that can occur, such as structural damage caused by damp. This can affect the masonry and structural timbers in your property. You can read more about structural damage caused by damp here.
If the job is only a small area of pointing, you may find a professional local builder, will be able to do the job in 1 day or less. If this is the case, you will only need to pay for materials (sand and cement/lime) and a day’s labour.
This could be anywhere between £150 – £300. Maybe even less for small jobs that do not take the whole day.
If you are having the whole house done, then this is quite a big job. It is also likely you will need scaffolding hire to do the work safely. In this instance you should usually expect to pay roughly £20-£30 per square meter of pointing.
Save money on pointing by comparing quotes
As with any job, you should always compare quotes. This is the best way, to get the best price.
At this point you have a few options:
- Recommendations from friends and family
- Calling around local builders
- Or comparing companies and reviews online.
Personal recommendations are always a good option, because you know they have performed a good service for someone you know. Alternatively, the next best thing is online comparisons, where you can read other customer reviews.
The best way to do this is via comparisons sites that rate and review companies. A popular service in recent years is Bark. They will get you as many as 5 local quotes.
Whats more, they are all rated by past customers on their company profile. This means you can find the best companies based on real customer feedback.
Prices also tend to be better. This is because the companies are competing against each other on price. Its not uncommon to see discounts as big as 50% on jobs like pointing.
As we have discussed poor pointing can be a serious cause of damp. It is a job that should be rectified sooner rather than later.
Whether you do small patch up jobs yourself or hire a professional contractor. Penetrating damp is never something you should just leave. The problem will get worse if it is not treated and the price could end up being much higher than the cost of repointing.