Damp-Proof Tanking: What Is It, How Does It Work, and Do You Need It?

Damping is a significant issue in most homes. It weakens the structure of a house, makes some living spaces inaccessible, and even affects your health. Unfortunately, homeowners don’t realise how big of a deal it is until it’s too late.

Damp-proof tanking is a way to protect your home from damping and other problems that it might cause.

Here’s a detailed article explaining what damp-proof tanking is and why you need to install it in your building.

How Does Damp-Proof Tanking Work?

Damp-proof tanking is a method used to prevent moisture from seeping through floors and walls. It involves waterproofing walls with a tanking slurry or membrane sheets, depending on what works for you.

Tanking creates a water-repellent barrier that prevents water and moisture from seeping into your walls.

Damp-proof tanking is usually applied on damp walls, especially those below ground level. Even if there’s no apparent moisture, it’s recommended that you still damp-proof them as these areas are prone to such issues.

Damp walls, particularly below ground levels, can lead to water ingress, cracks in the walls of your foundations, and other bad news for a home or building. All these can damage your living space and even affect your health. Avoiding these issues via damp-proof tanking is much more cost-effective than fixing them after they occur.

Can Damp-Proof Tanking Fail?

Damp-proof tanking can fail due to several factors. Some of them are:

  • Poor surface preparation
  • Tanking weak and unsuitable structures
  • Poor ventilation, etc.

Why Is Damp-Proof Tanking Necessary?

These are some of the reasons you should consider damp-proofing your walls:

Keep Your Home Safe and Dry

Prolonged wall dampness can lead to insect infestation, wood decay, and bacteria and mould accumulation in building materials. It can also cause metal corrosion of various fixtures in a home, like coils, wiring, and fasteners, which can also create trouble for your home’s structure.

With damp-proof tanking, you can protect your walls and floors from moisture and wetness. It also eliminates residual moisture. This will go a long way in maintaining your plaster, paint, flooring, and furnishings and, in effect, a building or home’s integrity.

Support the Utility of All Your Living Spaces

Moisture can build up in bathrooms, closets, the basement, and other areas without proper ventilation. This may render these locations inadequate for use or storing items, making the sites useless after a while.

Damp-proofing these surfaces will keep your living spaces dry and make it easier to make the most out of these areas without worrying about any of your items getting damaged.

Protect Your Health

Mildew, mould, and bacteria growth caused by damp floors and walls can worsen the health conditions of people suffering from respiratory issues like bronchitis and asthma. It can also trigger coughing, wheezing, and other respiratory illnesses in people.

What Are the Different Types of Damp-Proof Tanking Systems?

The two primary types of damp-proof tanking systems are tanking membranes and tanking slurry.

Here’s how each of them works:

Tanking Membrane

A tanking membrane is also called a damp-proof membrane. It’s a type of plastic sheet that serves as a waterproof barrier to prevent water from getting into walls and floors.

Made from high-density HDPE, it can endure long years of water exposure and temperature fluctuations without getting degraded or worn.

A tanking membrane is easy to install on damp walls, and creates a small cavity that dries the wall.

Tanking Slurry

Tanking slurry, or cementitious tanking, is a thick liquid coating that creates a waterproof barrier on the masonry surface.

This cement contains polymers and other aggregates that penetrate porous passageways in bricks and stones. It creates a watertight bond preventing water from penetrating the wall.

Overall, tanking slurry does an excellent job of promoting structural integrity, hygiene, and aesthetics. It’s a simple process; anyone with limited damp-proofing knowledge can apply it.

How Do You Install Damp-Proof Tanking?

Each damp-proof tanking system has its installation method. While these processes aren’t complicated, they still require some precautions or a trained eye to ensure they’re done correctly.

How Do You Install a Tanking Membrane?

The installation process of this tanking system is a bit more complicated than the slurry.

Here are the broad steps:

Measure the Wall

The first step is to accurately measure the wall area you’ll be fixing the material. It’s crucial not to rush this step, since it will determine how many rolls of membrane you need for damp-proofing the wall.

Prepare the Wall

Get rid of anything on the wall that might disturb the membrane installation, such as moulds and unstable plasters. Remember you’ll be using fixing plugs to hold up the sheet, so the wall has to be free of any obstructions.

Install Membrane on the Wall

Install the sheets on the wall by drilling holes through the membrane and hammering in the plastic fixing plugs with a rubber mallet. The spacing width for horizontal and vertical plug fixings differ, so check out the installation instructions in the membrane kit you buy.

On top of that, you need to ensure that the membrane is tightly fastened to the wall without any slack.

Close Off All Gaps

After fixing the membrane sheets, use waterproof tape to seal off any spot where water might squeeze through. You’ll find some areas around the fixing plugs, joints between the sheets, or places where the sheets meet the cavity drainage system or the floor.


Once you’re sure that you’ve installed the membrane sheet correctly, you can decorate it as you wish. Start by adding a dot and dab plasterboard.

Other options include building a timber framework before selecting a final decoration.

How Do You Install Tanking Slurry?

Tanking slurry is a kind of cement powder that you can mix and apply yourself. Here’s a simple guide to help you install the item correctly:

Prepare the Wall

Remove any fixtures or objects on your wall until it’s entirely bare. You should also remove every plaster and previous coatings like paints and bitumens. The point is to return the wall to its original masonry.

After that, you’ll have to repair its holes and cracks using a high-quality fillet seal.

The final step is to wet the walls to make the slurry bond with the substrate.

Protect Yourself

Once you’re done fixing the wall, you should protect yourself with the proper gear. This includes overalls and a mask.

This step is necessary because the chemical elements in the tanking slurry can be dangerous to the skin and eyes.

Prepare the Slurry

Mix your tanking slurry powder with just enough water to give the mixture a batter- or soup-like consistency. That means the combination mustn't be too thick or watery.

Apply Mixture on the Wall

After you’re done mixing, use a brush to apply it directly on the target wall. It’s best to apply the first coat horizontally and focus on the part where the floor meets the wall. Apply the slurry quickly, as it’ll start setting within 45 minutes.

After the first coating is dry, you can apply the second one. This time, it should be used vertically and within 24 hours after the first coating has dried off.

How Long Does Tanking Slurry Take to Dry?

It takes between 24 and 48 hours for tanking slurry to dry, and the process is called curing. It can occur at different rates for different wall parts, with wetter parts curing slower.

How Long Does Damp-Proof Tanking Last?

Damp-proof tanking should last up to 10 years but, if installed correctly, its lifespan can be even longer. Note several factors can affect how long damp-proof tanking lasts.

For instance, if your area sees a lot of rainfall or is prone to flooding, it may shorten the lifespan of your tanking system.

If your home is close to railway lines or busy roads, your tanking slurry might start to crack sooner.

If you notice anything wrong with your tanking system, seek the help of a professional instead of trying to fix it yourself. The latter can do more harm than good at times, and you may spend more just trying to repair the system through DIY methods.

What’s the Difference Between Tanking and Waterproofing?

Tanking and waterproofing have the same objective — to prevent water from getting into structures like basements, roofs, and buildings.

With tanking, you create a physical barrier against water by applying a waterproof membrane or tanking slurry to the surface of the wall. While the tanking slurry is technically a kind of cement, the membrane can be liquid-applied polyurethane, sheet membranes, or bitumen.

Meanwhile, waterproofing involves treating materials with substances that prevent water from soaking them. You can achieve this by using sealants, paints, and coatings.

You can apply a waterproofing system on wood, metal, and concrete surfaces. This method is mainly used to protect surfaces rarely exposed to standing water but still needs some form of protection against occasional exposure.

How Much Does Damp-Proof Tanking Cost?

The total cost of damp-proofing depends mainly on the damp treatment you’re using. For example, a tanking slurry in the United Kingdom is £30-£60 per square metre. A damp-proof membrane costs £100-£130 per square metre, while a damp-proof injection has an average cost of £70 per square metre.

Besides that, you’ll also need to pay labour charges which usually cost £100-£200 per day. Some companies might also need to survey the area before proceeding with the work, which can cost another £100-£200.

Overall, damp-proofing a wall can cost £300-£400, and for the whole house, you can spend anything from £300 to £5000.

Other factors that can determine how much you’ll spend on damp-proofing include:

  • Type of dampness
  • Number and size of walls
  • Location in the UK
  • The extent of damp damage

As you can see, tanking can be quite an investment. It’s why you should get a quote from a professional, who will consider all these factors and provide an accurate rate.

Do You Need a Professional to Install Damp-Proof Tanking, or Can You DIY It?

Many homeowners prefer DIY damp-proofing because it helps to save costs. Still, you should consider some factors before deciding whether you need a professional to install damp-proof tanking or if you can do it yourself.

The type of dampness will determine whether you can fix it or require expert help. For issues like condensation, a simple solution like improving ventilation or applying damp-proof paint can solve the problem. This doesn’t usually require any expert aid.

However, if you’re trying to fix a rising damp, then DIY methods usually won’t suffice. This might require damp-proofing injection, which only a professional can do. A damp-proof membrane can also be a great DIY project, but you might want to call on a professional if you aren’t confident you can handle it independently.

Do Damping Companies Offer Proof Tanking Guarantees?

Damping companies offer proof tanking guarantees, although the time frame can vary. A 10-year warranty is common, though some firms can offer more or less. You’ll be informed of the exact guarantee length when you reach out to a damp-proof tanking professional.


While damping is a common problem in many homes, the good news is that you can prevent it from damaging your home or your building. All you need to do is install the right damp-proof tanking system, and you’re good to go.

You can install a tanking slurry or membrane as a DIY project. But, if you want to make sure the system works for you, contact a damping proofing company for professional help.

Scroll to Top