How to waterproof a terrace?

Whether it is made of wood, natural stones, porcelain stoneware, or pressed concrete, the terrace is generally exposed to the elements.

Even if you use quality coatings, no material can withstand regular rainwater, scorching sun, humidity, and freezing wind.

Over time, these phenomena can cause significant damage. To avoid this, terrace maintenance is essential.

It is necessary to make it waterproof to prevent early deterioration and to extend its lifespan. To do this, there are many solutions, but water-repellent treatment is among the most used and effective options.

Which terrace water repellent to choose?

Before answering this question, it is important to provide you with the definition of water repellent. Unlike other treatments, this waterproofing agent serves to protect the terrace from moisture without altering its original appearance and color.

Because of rain or water infiltration, stains gradually appear and damage the floor covering. Through its saturation action, the water repellent product forms a protective film on the surface. 

Moisture attacks almost all building materials. If you wonder how to repair a water leak in a wall, the intervention of a plumber may be sufficient to solve the problem.

But when it comes to a wet terrace, a water repellent must be applied without delay to avoid worsening the situation.

Just like roof water repellent, the one dedicated to the terrace often comes in the form of a cream or liquid.

To choose the right product, it is important to know the different types of water repellents available on the market. We can distinguish 2 categories: solvent-based and water-based.

The first has the advantage of drying faster. Its drawback lies in its composition with harmful substances.

The second is both non-flammable and odorless. It can be used on almost all types of materials.

To avoid making the wrong choice, it is advisable to opt for a versatile product. It is suitable for all types of supports and materials.

How to waterproof a concrete terrace?

Waterproofing method	Drying time	Ease of application	Avg. lifespan
Liquid polyurethane resin	24 hours	High (Roller/Brush)	10-15 years
Bituminous membrane (Rolls)	Immediate	Medium (Torch applied)	15-20 years
Cementitious waterproofing mortar	48 hours	High (Trowel/Brush)	8-12 years
EPDM rubber sheet	Immediate	Medium (Adhesive bonded)	25+ years
Penetrating hydrophobic sealer	12 hours	Very High (Spray/Roller)	3-5 years

Despite its robustness, concrete does not resist excessive moisture when frequently exposed to bad weather. To prevent waterproofing problems, it is essential to seal it.

Before this operation, it is imperative to proceed with its cleaning. For the terrace to be ultra clean, vacuum as much fine dust as possible.

If possible, mop and use cleaning products. Try to respect the resting time according to the detergent chosen before applying the water repellent product.

For the latter to absorb effectively, the surface must be not only clean but also functional. To achieve this, make sure it has no cracks. Otherwise, the water repellent may be insufficient to resolve water infiltration.

Before carrying out the treatment, wait until the terrace is perfectly dry. Once done, you can proceed with the product application.

In most cases, it is imperative to apply two coats. Depending on the nature of the surface, two options are available to you.

For an uneven floor, the use of a brush is strongly recommended although it takes more time. If the surface appears smooth, you can use a paint roller.

No matter your method, it is recommended to wait for the first coat to dry before applying the second.

Note that the duration varies depending on the outside temperature and the type of product used. To avoid mistakes, it is wise to refer to the manufacturer’s instructions.

When to waterproof a terrace?

Like roof repair, terrace maintenance should not be done at just any time. Specialists recommend choosing a day that is neither too sunny nor too humid to start waterproofing.

Be careful of weather events. The product should not be applied during rainy weather. This condition prevents it from drying properly. It is advised to work in autumn or spring.

The water repellent can be applied on a new surface or once the waterproofing effect of a previous product has worn off.

If you choose a high-quality product, its effect can last for many years. Even if it is expensive, it guarantees the surface’s waterproofing for quite a long time.

Besides the various preparations, waterproofing a terrace requires following some safety measures. It is essential to equip yourself with protective glasses and especially a special mask that protects you from the harmful effects of a solvent-based product.

How to waterproof a slab?

This treatment guarantees its durability while protecting it from grease, oil, and moisture stains. It shields it from moss, frost, and the impact of humidity. Also, it helps preserve its original appearance.

Whether your slab is covered with gravel or smooth, it is easy to find the suitable waterproofing product on the market.

Before using it, it is useful to prepare the surface by cleaning it thoroughly. Start by removing all furniture. Then dust the floor with a vacuum cleaner.

The next step is cleaning with a scrub brush. Rinse with clear water. Let the terrace dry for two or three days.

For the water repellent product to be effective, the slab must be porous. To check, pour some water on the floor. When the liquid is absorbed within three minutes, the surface is porous.

If it stagnates on the slab and forms a puddle, your terrace is therefore not porous. It is necessary to open the concrete.

To do this, use one liter of hydrochloric acid mixed with four liters of water. Always remember to follow the safety instructions provided by the manufacturer.

Once this step is finished, use a watering can to pour the solution all over the slab. Allow one hour for it to act. After rinsing with clear water, let it dry for two days.

Now that the surface is porous, you can apply the waterproofing product with a sprayer.

After the first coat, let it dry first, then apply the second. You must wait a whole day before using your terrace and putting all the furniture back in place.

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