Damp proofing concrete floors – 3 Popular Solutions


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In this article we will be looking at 3 popular ways of Damp proofing concrete floors. all three solutions can be DIY without the need to pay professional.

When we think of damp, often we think of walls and ceilings. After all, this is where the tell-tale signs of damp are usually first spotted – discolouring and damp patches, black mould spots in the corner of a ceiling, or flaking paint coming off a wall – but floors can be affected too. A damp proofing concrete floor solution is particularly important. This is because damp rising up through concrete floors is a pretty common issue.

Damp proof membranes are routinely used during the construction of a concrete floor. However, typically these are often fairly thin and are sometimes damaged even before they are laid. Of course, if this does happen, they are essentially ineffective from the off. In basements, garages and old buildings where exposed concrete floors tend to be found the most, damp can become an issue too.

The consequences of not damp proofing a concrete floor are obvious, especially once a floor covering is placed on top. Carpets will become damaged and wooden floors will be prone to warping. Indeed, it’s not just these first signs of damage that can prove costly. Mould and mildew often forms on damp concrete. This can appear on the underside of a floor covering (carpet or wood), and if left untreated the mould can spread to the walls and cause a mould infestation.

So, damp proofing concrete floors can’t be ignored. Fortunately, there are several ways to do it.

Damp proofing concrete floors with a Liquid Membrane

Damp proofing concrete floors with a liquid membraneA liquid-applied DPM (damp proof membrane) is a simple solution and an excellent way to damp proof a concrete floor. It might seem a bit unusual. You are essentially painting a concrete floor, after all! But it is an effective way to do it. Once the liquid membrane has been applied to the concrete and it dries, an extremely hard surface is created that is impenetrable for damp.

Applying a liquid membrane is usually the best option whenever the final surface of concrete is going to be covered, such as a carpet or wood flooring. Liquid membrane products tend to have good adhesive qualities and impressive drying times.

If the damp proofing concrete floor solution is for a basement, the same membrane is usually applied to the walls at the same time. This effectively creates an airtight seal through which moisture cannot break.

It’s also good to know that the work involved in applying liquid membrane isn’t too arduous. It is important that the surface is clear and smooth but no priming is necessary. Liquid membranes need to be applied in two coats. The first being touch dry (normally an hour), and the second coat needs to be applied within 24 hours of the first.

Damp proofing concrete floors with an Epoxy Floor Coating

Damp proofing concrete floors with an epoxy floor coatingThis damp proofing concrete floor treatment is most commonly seen in industrial settings. The likes of warehouses, light industrial factory environments or storage areas are the places you are most likely to use an epoxy solution.

However, an epoxy floor coating is suitable for any surface where a floor covering is not going to be placed on top. Indeed, this is the real advantage of this method as it enables the surface to be walked on directly. The surface can even withstand light vehicle traffic too – making this treatment ideal for garages. In a domestic setting, garages are where epoxy floor coatings are used the most.

Application is a little bit trickier than for a liquid membrane. It is a two-coat job, but care has to be taken to ensure that both coats have a thin coverage of film. Most epoxy products come in two parts that need to be mixed before applying.

Damp proofing concrete floors with a Plastic membrane

Damp proofing concrete floors with a Plastic membraneThe easiest solution for damp proofing concrete floors is to install a plastic membrane. Essentially, this is a plastic mesh sheet specially formulated to ensure that moisture cannot penetrate. It sits between the concrete and the underlay floor covering. All types of floor coverings can be installed on top of a plastic membrane. For below ground installations, a drainage channel system is attached.

The good news is all of the mentioned damp proofing concrete floor solutions are relatively inexpensive and relatively easy to apply or install.