How to waterproof a terrace: Steps to follow

After the pandemic and all the time we have spent cooped up indoors, living in a home with a terrace is almost a privilege, as it has many advantages, but also some disadvantages that we must keep in mind.

When the weather is good, it is a pleasure to enjoy the sun without having to leave the house, but when the weather is bad, it is better to avoid disappointment and be prepared with solutions that protect our terraces from the rain and other inclement weather.

For this purpose, there are different waterproofing systems, each one for different surfaces and with particular characteristics. Thus, on the market we can find asphalt waterproofing, acrylic waterproofing, cementitious waterproofing or prefabricated waterproofing.

It is important to know that most of these actions on walkable roofs in new construction are carried out with waterproofing membranes, PVC sheets, asphalt, etc. However, continuous or liquid membranes are the ones most recommended by experts for waterproofing terraces.

Step by step

The procedure with this technique is very simple. The first thing to do is to prepare the substrate. It is essential that the surface is clean, dry, non-disintegrable and in perfect condition to receive the waterproofing. Next, it is necessary to locate the weak points: in the event of detecting any sensitive points, the first thing to do is to treat them. A good way to do this is to place an elastic band around the expansion joints and sharp cracks.

The half-rounds, these vertical-horizontal (wall-floor) joints, must then be located and made. Laying with mortars from the TECHNO range can help to reduce the stresses that a membrane applied at a 90-degree angle can receive. It is at this point that an elastic band can be applied to the entire perimeter before application to the entire surface.

For a perfect result it is necessary to apply two coats of waterproofing: in the 1st coat a fresh coat is applied and then the reinforcing mesh is placed on top of it and the brush is brushed over it again so that the mesh is practically invisible. Finally, the second coat is applied once the first coat is completely dry, leaving the mesh invisible.

What exactly does terrace waterproofing consist of?

The main function of waterproofing the walkable terrace is to avoid disasters caused by different weather conditions. This process should be seen as a long-term investment and not as an expense.

As we have said, there are many options, but without a doubt, the option of waterproofing our old terrace without removing the floor is the most convenient and quickest. Rubber paints can be installed on any surface exposed to humidity that needs to be treated with a paint with an anti-drip and anti-humidity effect and which at the same time has the function of waterproofing.

If our surface is covered with tiles, we will use a special paint for this type of floor. They are very easy to apply, as all we need is a brush to spread the paint very well. They are normally quick-drying, although it is recommended to let the product dry for at least 24 hours for a better result.

How to waterproof a terrace with Molins products?

Molins offers a complete range of products for waterproofing these highly sought-after spaces in our homes, and also for doing so quickly and, above all, comfortably:

These include liquid waterproofing membranes that are laid under ceramic tiles such as PROPAM IMPE FLEX. Its double consistency allows it to be applied by trowel, covering certain irregularities, or by brush, as required. It stands out for its compatibility with practically any building material.

PROPAM IMPELASTIC, on the other hand, is another liquid waterproofing solution suitable for small terraces that prioritises speed of execution (the coating can be applied just four hours after the second coat).

Other complementary solutions to membranes such as the BETOFIBER GLASS reinforcement mesh or the BETOTAPE SEAL elastic bands for expansion joints and cracks with possible movement are also in this line.

There are also liquid waterproofing membranes on the market that already offer an aesthetic finish, without the need for a ceramic coating. They are used for terraces with little or no traffic; these include solutions such as BETOPAINT 91 FIBRES, used together with the BETOFIBER POLIESTER body mesh. For busy terraces, there is also PROPAM PUR HYBRID (as you can see in the link hybrid polyurethane membrane) or PROPAM PUR.

Advantages of each option

Some of the common advantages of these products are their high adhesion to the substrate, they can also be applied on wet substrates in the case of cementitious products, they resist permanent immersion in most cases, they are impermeable to positive and negative pressure in the case of cementitious products, and they are permeable to water vapour.

They are also easy to apply and maintain, are economical solutions that are distributed in small packages for all types of surfaces, and have decorative finishes such as acrylic or polyurethane. In addition, some of them are suitable for contact with drinking water.

Aspects to take into account before waterproofing a terrace

Finally, before waterproofing our terraces, it is important to consider some previous steps so that the process and the result are always optimal.

First of all, it is vital to know the state of the surface. This will help us to choose which material to use or, if there are any cracks or fissures, to consider other options. It is also important to know the slope, which ends in drains, as this will help a lot with the material we use, making the whole process easier.

The use of the terrace will also be decisive, because depending on this, we will evaluate which solution to use and the approximate time needed for its transit. And, first of all, taking into account the time to carry out the process will be fundamental so as not to spoil all the work.