Type C waterproofing membrane installed on internal walls

The Different Types of Waterproofing

Waterproofing your property is a vital step in protecting your property against the potentially devastating effects of water ingress, and the damage that liquid and moisture can wreak on any home or building.

In fact, one of the leading causes of property decay is an abundance of moisture, with its consequences branching out into the likes of damp, black mould and even rot. With all that in mind, it might be important for you to learn about the different types of waterproofing services available, and how they could potentially protect your property from water ingress and damage.

The Standard for British Waterproofing

Ahead of the explanation of the different types of waterproofing available today, it’s important for you to understand that every type of waterproofing available to properties in the UK adheres to BS8102:2009.

BS8102:2009 is the code of practice for the protection of below ground structures against water from the ground. A long title, but it is the British Standard against which all waterproofing must be measured against, and BS8102:2009 itself provides advice and guidance on the different methods of waterproofing, as well as defining the three accepted types of waterproofing protection available to use within the UK.

Type A Waterproofing: Barrier Protection

The first type of waterproofing that most people come into contact with is Type A. As stated before, type A is also commonly known as barrier protection, but it can also be referred to as ‘Tanking’.

How Does Type A Waterproofing Work?

This is a method of waterproofing that involves the application of a waterproof material to a below ground structure. The material in question can be applied to one of three places; the interior, exterior or sandwiched within the walls and flooring of the below ground property itself.

As for the material used, there are commonly two types of tanking materials applied to below ground structures. The first is a multi coat render. This is typically applied like mortar to the interior of a property, but in some cases it can also be adhered to the exterior of the wall.

More commonly you may find a bonded sheet membrane applied to the walls. A bonded sheet membrane acts as a solid wall of protection on the walls of your property, attached like plasterboard, which can offer protection from water making its way to the inside of the property.

These are different methods of achieving the same objective, a Type A orientated waterproofing solution. It’s important to note as well that if applied correctly on its first installation, that this is a waterproofing system that requires no ongoing or routine maintenance. In fact, if it is installed professionally, then you may never again even notice that it has been installed on your property, only that your home is entirely waterproofed.

Potential Problems With Type A Waterproofing

However, that peace of mind does come with a few drawbacks, the first and most notable of which is that if it is installed incorrectly, or with any slight fault, then water will be able to penetrate into your property.

That means that throughout the entire installation process, you have to be sure that the experts carrying out the installation are adept, as confidence in the installation is the only metric you have for success. The application cannot be tested during its installation at all.

The installation of a 100% defect free Type A waterproofing solution is only made more difficult when you understand that in wet weather or bad groundwater conditions, the application can be made even more difficult. Installation is definitely the hardest and most vital part of any Type A waterproofing solution, and ensuring the installation is faultless is crucial in its future performance.

Another problem potentially posed by a Type A waterproofing solution is the displacement and movement of existing water surrounding the property. Naturally occurring drainage channels in the ground surrounding your property may become impeded by a Type A waterproofing solution.

This can lead to the water travelling further around your property where it could possibly find its self in an area which had previously remained dry and suffered from no water issues at all.

The point here is that a correctly installed Type A waterproofing system could displace water around your property, causing issues where previously you had none. Do not forget either that this is a system designed to keep water out of your property.

This is valuable information, as you might experience a build up in hydrostatic pressure, which in turn could compromise your waterproofing solution. Hydrostatic pressure occurs when the build up of moisture within the earth surrounding your property causes the soil and earth to shift and move horizontally, applying pressure to your properties underground walls upon contact.

If enough pressure is applied, your walls can crack at a vitally vulnerable point when it comes to water ingress, and you could potentially have a big issue on your hands.

All of these points are worth considering, but it is worth remembering that if done correctly, this is a waterproofing system that can keep your property safe with minimal upkeep or ongoing maintenance.

Type B Waterproofing: Structurally Integral Protection

Type B waterproofing systems are different to the other two types of waterproofing in that the waterproofing is handled entirely by the design and materials of the property itself. You will usually find Type B waterproofing systems in place within newer buildings.

How Does Type B Waterproofing Work?

Usually, Type B waterproofing is undertaken with materials such as a concrete bonding membrane. This membrane acts exactly as you would expect it to, with the waterproof concrete forming a seal on both the flooring and walls of the property itself. Materials, like the waterproof concrete, will be used throughout the below ground structure, in tandem with design implementation such as water stops.

Water stops act as barriers and are sometimes constructed separately from the property itself. They are installed by the construction company as part of the initial build out process to stop water from making its way to the building itself.

These water stops will be made of the same waterproofing materials used in the building itself, with the sole intent of diverting water away from the property as it travels through the ground, securing it further against below ground saturation and water ingress.

One thing to bear in mind with Type B waterproofing solutions is that it is usually only available on new build properties, and often more popular in larger constructions – especially ones with deep basements, for example car parks, built in.

That isn’t necessarily a drawback, however, If correctly installed, a Type B solution can keep a building secure from the moment its erected right up until it is dismantled. It is worth remembering though that the actual security against water ingress is only guaranteed if the fit-out process was 100% successful.

Potential Problems With Type B Waterproofing

There are a lot of variables to consider during the construction process that could lead to a failure of a Type B waterproofing system. The quality of materials, the placement and actual installation all need to be perfect in the first instance, otherwise the waterproofing will be ineffective. What makes this difficult is that similar to Type A waterproofing, the system cannot be tested at all as it is being implemented. Instead, you have to rely on the expertise of the engineers installing the system itself.

You also have to consider the same factors as with Type A. Hydrostatic pressure can always lead to potential failure, and within the joints of the building itself is an area particularly susceptible to failure. Always ensure that land drainage has been taken into account when it comes to Type B waterproofing, as a build up of moisture could prove catastrophic – and hard to repair.

Remember that Type B waterproofing systems are reliant on the design and materials of the building themselves, so if repairs must take place it could potentially mean digging out foundations, repairing structurally vital elements – a lot of hard and intricate work.

The final consideration you have to take is on the placement of the water stops. If they are incorrectly positioned, if they do not allow adequate protection from moisture or if they damage the property itself in overflow or when pouring, then there could be a serious issue for the building.

Often, to account for these potential issues, a separate waterproofing solution is undertaken in conjunction with Type B waterproofing, just to ensure that the building itself is totally secure from any water ingress. This may also involve the implementation of a Type A system, as well as a Type B system, but either way it’s the only way to ensure protection against any form of water ingress. This can be costly, but the end results are often worth the effort and price.

Type C Waterproofing: Drained Protection

How Does Type C Waterproofing Work?

Type C waterproofing, or drained protection waterproofing, is the process of applying cavity drainage membranes and drains within a property that collect water after it has travelled through the walls of a property, before channelling them through the installed drains to a sump pump system, which then safely pumps the water away and removes the water from the property into the correct or safe nearby channels.

Benefits Of Type C Waterproofing

According to BS8102:2009, Type C waterproofing is ‘considered to be the most effective and trouble free form of basement waterproofing.’ This is down to a couple of reasons, the first and foremost being that the water is not being suppressed or actively stopped from entering the property.

This means that water build up and hydrostatic pressure won’t be a concern, and that the areas of entry for the water will be easily identified and not change after the installation of the waterproofing system.

The second reason that Type C waterproofing is so popular is that it is easily installed – even in properties that have existing or failed waterproofing solutions built into them. That’s because the fit out of Type C waterproofing takes place over the existing walls, forming a brand new, completely clean and dry surface on which you can fit plasterboard and then decorate as normal. This makes the Type C waterproofing solution especially popular with designers and refurbishment.

You will also find that Type C waterproofing is popular because it can easily be combined with another waterproofing solution to ensure total protection, or to round out a new build as part of a combined solution. In this situation, the property will be protected both inside and out against any major amount of water ingress, or potential failure of a Type A or B waterproofing system.

The perimeter drainage channel, which is where the water collected by the membrane drains to, is also easily accessed via inspection ports. These channels are installed into the floor, and can be easily accessed via hatches so that they can be inspected and cleared routinely, meaning that there is a minimal risk of clogging or build up.

Perimeter drainage channels all lead to the sump pump. The sump pumps is a vital part of the cavity drain method of waterproofing, and if it were to fail then it could lead to an overflow, which in turn could flood a basement if left unchecked.

So, the sump pump is also made accessible via a hatch in the floor, as it will be installed in a dug out position. This means that engineers can access it for routine maintenance, ensuring steady operation all year round.

All of this comes together to offer up a waterproofing solution that doesn’t just offer predictable results, but one that also closes the gaps where other waterproofing systems are slightly lacking. The system can be checked during its installation to see if it’s working as expected, and repair is made easy thanks to how it is installed and the accessibility of the system itself.

Problems With Type C Waterproofing

That’s not to say it isn’t without its potential drawbacks. You must ensure that a Type C waterproofing system is installed by qualified professionals to ensure its reliability. It may be installed quickly thanks to adverse weather and conditions not having an impact on its installation unlike other waterproofing systems, but if it isn’t installed by experts then you may develop a problem quickly.

You should also consider that lime deposits, sump pump motor failure, and drainage channel blockages are all possibilities that need to be accounted for. To that end, routine and scheduled maintenance needs to be upheld on both the waterproofing system and the pump itself to make sure that it works as intended year in year out, which is more than the other solutions require.

However, on balance, routine maintenance will highlight any potential issues, and allow them to be fixed in a much easier and quicker manner than other waterproofing solutions.

More Advice On Types Of Waterproofing Systems

If not sure what waterproofing system you have at your building or you would like to explore the options in safeguarding your basement against the potentially devastating effects of water damage, do not hesitate to call Timberwise today.

As property care specialists, our team of expert waterproofers across England, Wales and Scotland are more than capable of surveying, suggesting and installing a waterproofing system that is right for your building and that will maintain and protect its build quality against the ravaging effects of damp, leaks and mould. Call 0800 288 8660 or visit our contact page to arrange a waterproofing survey today.