How Long Does Damp Proofing Take? 7 Common Damp Repair Jobs

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how long does damp proofing take

Damp can be a complex issue. There are many different reasons it can occur in your property and this means there is no single way to fix it. Different damp problems will require different damp solutions.

In this article, we will be looking at how long damp proofing takes. We will cover 7 different damp proofing jobs. Most of these are tasks that can be performed by a competent DIY’er. However, some people may prefer to hire a professional in some cases.

Because there are so many causes and solutions for damp the timeframe to resolve it can vary. Certain small jobs may take as little as 1-2 hours. Whereas larger jobs like installing a brand new damp proof course, could take as long as 2-3 days.

You should also consider that a professional is likely to be faster than a DIY’er. This is simply down to practice and experience.

There are plenty of DIY jobs that can be carried out by the homeowner to stop damp. This will all depend on your level of confidence and any prior experience you might have.

Seven of the most common damp proofing jobs can be seen below:

1 – Damp proof painting – 1-2 hours for a standard sized room

As with any kind of painting, applying a damp proof paint is not that complicated. To paint a standard sized room in a UK property with one coat of paint using a roller will usually take about 40 – 60 minutes.

This may take slightly longer with a damp proof paint as it is thicker than standard emulsion. However, it should not take much longer with a large brush or a roller. A small room can usually have a single coat applied in around 1 hour.

Also, it is worth considering how many walls you will be painting. When applying damp proof paint, it may only be one wall that is having issues. In this case the time to complete one wall could be significantly less.

Once applied most damp proof paints are dry within one hour. Following this you can apply a second coat or paint over with a standard emulsion.

2 – Tanking slurry – 4-6 hours for a standard sized room

A tanking slurry can be a fantastic way to add a waterproof membrane to any internal surface. It usually comes as a powder and just needs mixing with water.

The process is quite simple and can be performed by any DIY’er that is willing to put in a couple of hours work.

Before you start you will need to prepare the surface you are tanking. This will involve removing any dust and debris. You should also spray or brush the surface with water prior to application. This will prepare the surface and make the slurry adhere better.

In our experience, applying tanking slurry will usually take about 5-10 minutes per m2. So, the total time to apply one coat will vary on the size of the area. Applying to a floor will also be quicker than applying to walls, as the slurry can be spread with a soft sweeping brush.

A completed tanking slurry job will require 2 coats. Between coats you should leave the slurry to dry, this will usually take 1-2 hours depending on the temperature.

All in all, you will need to consider the 4 following things:

  • The surface area you intend to tank.
  • Time to prep the area before application
  • How long it takes to apply each coat of slurry
  • And finally, the drying time

You can learn more in our tanking slurry case study here

3 – External masonry Paint – 1 – 2 week for a whole house

Applying exterior masonry paint can be a big job. If you are planning on doing the whole house yourself, you could be in for a long, hard slog.

For any smaller areas, it is much like any other kind of painting and you should expect similar timeframes.

If you do intend to do an entire house, you need to be very prepared. This is not a small undertaking, and as the saying goes: “if you fail to prepare, then you should prepare to fail”.

Essentially, correct preparation will save you a lot of time and hassle. It is reasonable to assume that 50% of your time will be spent in prepping before you begin to paint.

In most cases, it would take a professional painter 3-4 days to fully paint a standard semi-detached property. For the DIY’er you can usually double this time.

To learn more about the entire process and read 10 tips for painting your own house click here.

4 – Injecting a chemical DPC – 1-2 day for a whole house

Injecting a chemical damp proof course is a great alternative to reinstalling a standard DPC. It is far less disruptive and requires far less technical know-how.

The biggest amount of time will be spent if you need to remove internal plaster. This is usually necessary in a standard cavity wall as you will need to inject the internal skin. This is for a couple of reasons. Firstly, you will need to see the mortar bed, so you are injecting in the correct place.

Secondly, you should be removing damp plaster. If you don’t remove damp plaster, this could lead to future problems, even after the chemical DPC is installed.

Injecting the chemical DPC is quite simple. You will need to drill holes in the mortar bed at regular intervals. Following this, you will simply inject the chemical DPC into the holes, using a standard mastic gun.

Once the chemical DPC has been injected, you will need to replace internal plaster. You could also consider applying a tanking slurry to the brickwork and skimming over the top. This would add an additional layer of protection.

Obviously, you will probably need a professional plasterer to apply the skim finish to this part of the job.

5 – Repointing – Up to 1 day for small jobs – Up to 1 week for a whole house

Repointing can be a big job, especially if you intend to do an entire house.

If you do need your whole house repointing, most people will be better off hiring a professional tradesperson.

A decent pro can complete a standard semi detached home in around 1 week. A DIY job could take much longer

However, if there is a small area of pointing that is obviously causing damp, then this is usually an easy job for the competent DIY’er.

Scraping out the mortar and repointing a small area could take as little as a couple of hours. This may be all that is needed to completely resolve a penetrating damp issue.

You can see a useful video that runs through the entire process below:

6 – Replacing a damaged brick – 1-2 hours

This is another relatively easy fix for the DIY enthusiast.

A damaged brick may seem like a minor issue. However, it offers a very easy way for moisture to penetrate your home. This can cause significant damage internally if the issue is not resolved.

To replace a brick, you need to take the following steps:

  • Drill around the brick to remove existing mortar
  • Chisel out and remove the brick
  • Clean away all remaining mortar, dust, and debris
  • Spray the hole with water to help new mortar adhere
  • Mix new mortar
  • Add new brick
  • Repoint around the brick

You can see a full video tutorial below:

7 – Reducing condensation – 10 Minutes

Penetrating damp and rising damp can cause major problems to a property. But they are nowhere near as common as condensation. If you have damp or black mould in your property and there are no obvious external issues. Then its likely condensation is the problem.

The good news is, there are simple ways to resolve condensation. These take little to no time and require no specialist knowledge.

Condensation is a result of excess moisture in your property. This is easily resolved by removing the excess moisture. The following steps can help to reduce condensation completely.

  • Maintain a good temperature with your central heating
  • Regularly open doors and windows to allow air to circulate.
  • Use a fan to circulate fresh air through rooms that are more prone to damp.
  • Use a dehumidifier

Also, for rooms that have higher levels of moisture, such as your bathroom and kitchen, you should consider installing extractor fans. This will cost a small amount of money, but in the long run it could save you future expense, by removing excess moisture that causes damp problems over time.


As you can see the time it takes to damp proof can vary quite significantly. There are small jobs that can take as little as an hour. Then there are bigger jobs that can take a week or more.

This article gives a few common examples. However, there are plenty of other damp proofing solutions out there.

The main thing you need to do is identify what is causing the issue. Once you know exactly where the damp is coming from you can easily find the best solution.