What is a waterproofing agent and how to use it on terraces, walls and roofs?

You may have heard this word but not be quite sure what a waterproofing product and what it is used for. Waterproofing is often one of those tasks left until the end, until the first damp stains or an unexpected leak appear. 

If you have dampness or leaks, or need to waterproof a swimming pool or terrace and are not quite sure what a waterproofing product is or how to use it on different surfaces, keep reading. We explain everything in this article. 

What is a waterproofing product and what is it used for?

When it comes to protecting a home from dampness or leaks, the first thing to know is what a waterproofing product is. It is not simply paint applied over a wall or floor, but a product designed to create a barrier that prevents water or moisture from seeping into materials. 

It can be used in many areas: walls, terraces, roofs, swimming pools, ceilings, or even wood, and it is essential for keeping a home in good condition over time.

In addition to preventing leaks or seepage, a waterproofing product protects building materials and improves the insulation and prevents mold or damp stains from appearing. Ultimately, it is an essential ally for maintaining the structure and appearance of any building.

Types of waterproofing products

When deciding how to waterproof a surface, it is important to know the different types of waterproofing products that exist. Understanding in depth what a waterproofing product is means learning that each area requires a different treatment and that there is more than one type of product for each surface. 

Acrylic waterproofing products

They are among the most widely used because they are easy to apply. They can be spread with a brush or roller and form an elastic film that adapts to the movement of the material. They work very well on terraces, rooftops, or flat roofs, where water tends to accumulate. 

Cementitious waterproofing products

They come in the form of a mixture of cement and polymers. They are ideal for areas in direct contact with water, such as swimming pools, basements, or tanks. 

Asphalt waterproofing products

They are made from bitumen or asphalt and are sold both as sheets and in liquid form. They withstand temperature changes well and are perfect for waterproofing a roof. 

Polyurethane waterproofing products

These are applied in liquid form and create a continuous, flexible layer without joints. They have excellent adhesion and are highly effective on terraces or roofs exposed to intense sunlight and rain. 

Wood waterproofing products

Wood requires specific care, especially outdoors. If you are wondering what to use to waterproof wood, there are oils, varnishes, and coatings that not only repel water but also nourish and protect the material so it lasts longer without cracking.

Where waterproofing products are applied

Waterproofing products are not used only on roofs or terraces. Part of gaining an in-depth understanding of what a waterproofing product is involves knowing which surfaces it can be applied to safely. 

• Exterior walls: they are the ones that suffer the most over time.
  
• Terraces and rooftops: to protect the surface from water and leaks. 
  
• Roofs and ceilings: the most important thing is to choose products with good adhesion and elasticity. 
  
• Swimming pools: swimming pools require specific products; just any product will not do. 
  
• Wood: wood is highly sensitive to moisture and, without protection, can warp or crack. 

How a waterproofing product works

The most interesting part of learning what a waterproofing product is involves learning how it works when applied. Its operation is simple but highly effective. It creates a visible or invisible protective layer that prevents water from seeping through. Some products form a surface film, while others penetrate the material, sealing the pores from within.

The result is a surface that is more resistant to water, mold, and wear. Best of all, with basic maintenance, this protection can last for years.

Which waterproofing product is best for exterior walls

Choosing the best waterproofing product for exterior walls can make the difference between having an impeccable facade and ending up with damp stains and peeling paint every winter.

Before choosing a waterproofing product

Before deciding which waterproofing product is best for exterior walls, several key factors should be considered. 

• The type of wall material: waterproofing brick is not the same as waterproofing concrete or stone. Each has its own requirements.
  
• The local climate: if it rains a lot or there is constant humidity, a more resistant and elastic waterproofing product is advisable. In very sunny areas, it is better to use one with UV protection.
  
• The desired finish: there are transparent products that preserve the wall’s original appearance, and others that cover it completely, adding color or shine.
  
• The application: some are applied with a brush or roller, while others are applied with a spray gun. If you want something simple, liquid waterproofing products are the most practical.

Types of waterproofing products for exterior walls

Knowing what a waterproofing product is helps explain why there are so many options. They do not all work the same way or serve the same purpose. 

• Acrylic waterproofing products: they are the most common and easiest to apply. They form an elastic layer that prevents leaks and adapts to wall movement. 
  
• Siloxane waterproofing products or water repellents: they are transparent and penetrate the material without altering its appearance. They are ideal for exposed brick, natural stone, or cement. 
  
• Polyurethane waterproofing products: they offer excellent resistance to sunlight, rain, and temperature changes. They are usually applied in liquid form and create a continuous layer without joints. 
  
• Cement-based waterproofing products: although they are mainly used in swimming pools or basements, they also work well on concrete walls that are in contact with the ground or moisture. 

How to apply waterproofing product to exterior walls

Once you have chosen the best waterproofing product for exterior walls, the most important thing is to apply it correctly. 

Prepare the surface

• Clean the wall thoroughly: remove dust, mold, paint residue, or grease.
  
• Repair cracks or joints before applying the product.
  
• Make sure the surface is dry; moisture prevents the waterproofing product from adhering properly.

Applying the product

• Apply a coat of sealer if the wall is very porous.
  
• Apply the waterproofing product with a brush or roller in crisscross strokes to cover all the pores properly.
  
• Let it dry according to the manufacturer's instructions and apply a second coat if necessary.

Inspecting and maintaining

Although waterproofing products usually last for years, it is advisable to inspect the walls from time to time, especially after heavy rain. A quick touch-up can prevent more serious leaks.

How to waterproof a terrace step by step

Knowing how to waterproof a terrace correctly is one of those tasks that saves a lot of trouble in the long run. Terraces are constantly exposed to sunlight, rain, and temperature changes, so it is normal for cracks, leaks, or damp stains to appear over time. 

Preparing the terrace before waterproofing

Before applying the product, waterproofing product or thermal and acoustic insulation the surface must be prepared. Poor preparation can prevent the waterproofing product from adhering properly or cause it to peel off soon afterward, so this step is essential.

Cleaning and checking the condition of the terrace

• Sweep and clean the entire surface thoroughly to remove dust, leaves, and dirt.
  
• If there are traces of paint or old products, remove them with a spatula or brush.
  
• Check for cracks or open joints and repair them with filler or mortar.
  
• Make sure the terrace has a sufficient slope so that water does not remain stagnant.
  
• Let the surface dry completely

Choosing how to waterproof a terrace

When deciding how to waterproof a terrace, you need to consider the type of surface (cement, tile, stone, etc.) and its exposure to sunlight and rain. Not all products work the same way, and choosing the right one ensures a better result.

The waterproofing products the most commonly used on terraces are acrylic, polyurethane, cement-based, and liquid rubber or elastomeric products. 

How to apply waterproofing product step by step

On very porous or old surfaces, it is advisable to apply a primer before the waterproofing product. This improves adhesion and prevents the product from being absorbed too quickly.

Apply the waterproofing product

• Stir the product well before using it.
  
• Apply the first coat with a roller or brush, always in the same direction.
  
• Allow it to dry completely (check the time indicated by the manufacturer).
  
• Apply a second coat crosswise to the first to cover all the pores thoroughly.
  
• In the most exposed areas, you can apply a third reinforcing coat.

Allow to dry and protect

During drying, avoid walking on the surface and make sure it does not rain. On large terraces, placing a reinforcing mesh between layers improves the waterproofing product’s strength and durability.

How to waterproof a roof without mistakes

Learning how to waterproof a roof correctly is one of the most important tasks in any home. The roof is the first barrier against rain, sunlight, wind, and temperature changes, and if it is not properly protected, leaks can eventually affect the entire structure. 

Types of roofs and how to protect each one

Not all roofs are the same. Before starting to waterproof, it is important to be clear about what type of surface will be treated, as this will determine what can be used to waterproof a roof and which technique to use.

Sloping roofs

These are the most common roofs in private homes, generally covered with ceramic or slate tiles. In these cases, water runs off easily, but problems usually arise at the joints or with displaced tiles. 

The key to waterproofing for complete protection is to apply a paint or waterproofing product liquid over the entire surface, paying special attention to the joints.

Flat roofs or accessible roof terraces

Here the challenge is different, as water can easily accumulate. The technique is similar to “how to waterproof a terrace,” and the important thing is to choose the right product for waterproofing a terrace or the roof itself. 

The most recommended products are polyurethane or liquid rubber, which form an elastic, continuous layer that withstands rain and sunlight perfectly.

Metal or sheet-metal roofs

They are widely used in industrial buildings or lightweight constructions, although they can also be found in some homes. Their main enemy is corrosion. To protect them, it is best to apply an acrylic or polyurethane waterproofing product that adheres well to metal and prevents rust from forming.

How to waterproof a roof step by step

Once you have identified the type of roof, it is time to get to work. 

Choosing the right waterproofing product

Knowing what waterproofing is helps you understand that not all products work the same way. Choosing the most suitable one for the type of roof is essential:

• AcrylicEasy to apply, ideal for tiled or concrete roofs. They allow the material to breathe and prevent condensation.
  
• Polyurethane: resistant to standing water and sunlight. Perfect for flat roofs or roof terraces.
  
• Bituminous: available as sheets or in liquid form, they are durable and highly effective against heavy rain.
  
• Liquid rubber: they adapt to any surface and create a continuous, seamless layer. They are a great option if you are looking for a durable and flexible solution.

Cleaning and preparation

• Remove leaves, dust, or dirt.
  
• Repair any cracks or open joints with filler or sealant.
  
• Make sure the surface is completely dry before applying the product.
  
• Product application
  
• Apply a primer if the roof is porous.
  
• Apply a first coat of the waterproofing product with a roller or brush, thoroughly covering the entire surface.
  
• Allow it to dry for the time indicated by the manufacturer.
  
• Apply a second coat crosswise to the previous one to ensure complete coverage.
  
• Reinforce the most delicate areas (chimneys, gutters, skylights, or joints) with an extra coat or reinforcing mesh.

How to waterproof roofs with special features

Some roofs require a little more attention and tools and equipment special:

• With skylights or roof windows: make sure to seal the edges properly before applying the waterproofing product.
  
• With solar panels: apply the product without covering the anchors or metal fixing points.
  
• In very humid areas: combine the waterproofing product with moisture-resistant paint to reinforce the protection.

How to waterproof outdoor wood

Knowing how to waterproof wood is essential if you want to keep it beautiful and in good condition for many years. Wood is a natural material that brings warmth and style to any space, but it is also delicate: if it is not properly protected, sun, rain, or moisture can cause it to crack, fade, or even rot over time. 

Types of wood waterproofing products

Not all products serve the same purpose. When deciding how to waterproof wood, you need to consider whether it is indoors or outdoors, the type of exposure it faces, and the desired finish.

Natural protective oils

Oils (such as teak, linseed, or tung oil) are a very popular option because they nourish the wood from within. They penetrate the pores and make it more water-resistant while enhancing its natural color. They are perfect for floors or garden or outdoor furniture, although they require periodic maintenance, as their effect gradually wears off over time.

Marine or water-based varnishes

Marine varnishes create a protective film resistant to sun, rain, and salt. They are ideal for doors, windows, or outdoor structures. If you prefer a more understated finish with less shine, water-based varnishes are a good alternative, as well as being more sustainable and easier to apply.

Polyurethane waterproofing products

If strong, long-lasting protection is what you are looking for, polyurethane waterproofing products are a safe choice. They form an elastic, highly resistant layer that prevents water from penetrating. These products are also used for other projects, such as waterproofing a terrace or even a roof, since they offer great versatility and resistance.

Wood stains with UV protection

Wood stains are another highly effective option, especially for outdoor use. Unlike varnish, they allow the wood to breathe and do not crack over time. In addition, many include UV filters that protect against sunlight without altering the material's natural color. They are ideal for fences, pergolas, or cladding.

How to waterproof wood step by step

Once you have chosen the product, it is time to apply it properly. Knowing how to waterproof correctly is what ensures a long-lasting result.

Prepare the surface

• Sand the wood gently to open the pores and remove old paint or varnish residue.
  
• Clean off the dust thoroughly and make sure it is completely dry before starting.

Apply the waterproofing product

• Stir the product so that it is uniform.
  
• Apply the first coat with a brush, following the direction of the grain.
  
• Allow it to dry for the recommended time and apply a second coat to reinforce the protection.
  
• If the wood is highly exposed to sunlight or rain, add a third coat for greater resistance.

How to waterproof a pool step by step

Knowing how to waterproof a pool correctly is essential to prevent leaks, seepage, and moisture problems that could eventually damage the structure. Always remember to do so with pool-specific products. 

What to consider before waterproofing a pool

Waterproofing a pool requires more than applying a product and waiting for it to dry. Several factors that will directly affect the outcome must be considered:

• The pool's material: a concrete or mosaic-tile pool is not the same as a prefabricated one. Each type requires a different waterproofing product.
  
• The condition of the surface: if there are cracks, open joints, or damp areas, they must be repaired first.
  
• Exposure to sunlight and the elements: in outdoor pools, sunlight and temperature changes can affect the product's durability.

Most commonly used waterproofing products for pools

When deciding how to waterproof a pool, the most important thing is to use products specifically designed to withstand pressure and continuous contact with water.

Cementitious waterproofing products

They are the most common choice for tiled or concrete pools. They are easy to apply with a brush or roller, creating a sealing layer that prevents leaks. They also allow coverings such as mosaic tiles or ceramic tiles to be installed on top without losing adhesion.

Liquid polyurethane or acrylic membranes

They form a continuous, flexible film that adapts perfectly to any shape or corner. They withstand humidity and structural movement well. In fact, these types of products are also used for waterproofing a terrace or waterproofing a roof, as they provide very long-lasting protection.

Epoxy resins

Although they are usually more expensive, epoxy resins are one of the most durable options. They create a smooth, waterproof, glossy surface, ideal if you want a decorative finish without having to coat the pool.

PVC tarpaulins or sheets

For prefabricated or deteriorated pools, PVC sheets are a practical alternative. They act as a waterproof coating that prevents leaks and can be installed quickly without construction work.

How to waterproof a pool step by step

Good preparation is half the battle. If you want the waterproofing product to last and work effectively, you need to follow a few basic steps.

Prepare the surface

• Thoroughly clean the entire pool, removing paint, mold, or grease residue.
  
• Repair cracks with special mortar or a suitable sealant.
  
• If the pool is new, make sure the concrete is completely dry before applying anything.

Apply the waterproofing product

• If indicated by the manufacturer, apply a primer coat to improve adhesion.
  
• Apply the first coat of waterproofing product with a brush, roller, or trowel.
  
• Let it dry for the recommended time and apply a second coat in a crosswise direction.
  
• Pay special attention to corners, joints, and areas where leaks commonly form.

Install the final coating

Once the waterproofing product is completely dry, the chosen finish can be installed: mosaic tiles, special paint, or epoxy coating. Each material has its own curing time, so it is advisable to follow the manufacturer's instructions.

Professional recommendations for a long-lasting finish

Learning what waterproofing is is not just about knowing what the product is and how to apply it; it also means knowing how to achieve a result that lasts for years without deteriorating. 

• Do not skimp on quantity: applying the product generously and evenly ensures complete coverage.
  
• Respect drying times: each coat needs time to harden. Do not rush steps or walk on the surface too soon.
  
• Apply under suitable conditions: avoid rainy days, high humidity, or extreme temperatures. Ideally, work in mild, dry weather.
  
• Regular maintenance: Inspect the surface once a year and apply a new coat if worn or porous areas are detected.

What is the best time of year to waterproof each surface?

Choosing the right time to apply a waterproofing product is almost as important as knowing what waterproofing is or how to waterproof correctly. That is why planning the right time for each surface is key to ensuring the work is perfect and lasts longer.

Exterior walls

Ideally, do it in spring or at the beginning of autumn, when temperatures are mild and the air is not too humid. In winter, cold and rain can affect drying, while in midsummer, extreme heat can cause the product to crack or lose adhesion.

Terraces and roofs

Whether you are considering how to waterproof a terrace or how to waterproof a roof, it is best to do it before the rainy season. The spring months or late summer are perfect: the weather is good, the product dries well, and the surface is ready to withstand autumn and winter. If a polyurethane or resin waterproofing product is used, it is best to avoid very hot days, as it could dry too quickly.

Interior ceilings

The weather is not as important for interiors, but it is important for the area to be well ventilated and free of moisture. If it is an exterior roof, follow the same recommendations as for a rooftop: dry weather, moderate temperatures, and no rain in the days following application.

Exterior wood

Spring is usually the best time. The temperature is mild, and the air is not as moisture-laden as in winter. In addition, if you do it on dry days, the product penetrates the wood's pores better and provides protection for longer. 

Swimming pools

When it comes to waterproofing a swimming pool, it is best to do it before summer. In other words, between the end of spring and the beginning of the hot season. 

Conclusion

Ultimately, understanding what a waterproofing product is and how to waterproof each surface is the basis for preventing leaks, dampness, and dripping for years. 

Knowing which is the best waterproofing product for exterior walls, what to use to waterproof a terrace, or even how to waterproof a roof may seem complicated at first, but with the right information and products, the result is worth it. 

Properly preparing the surface, applying the product carefully, and doing so at the right time of year will make the difference between long-lasting protection and a temporary fix.

Waterproof with Brikum

At Brikum, we are clear about one thing: a good result starts with a good product. In our online store, you will find better building materials to renovate your home and repair any damage. Not only in your home, but also in your garden or swimming pool.  

We work with waterproofing products acrylic, cement-based, polyurethane, or asphalt-based products, designed to offer maximum protection against water, sunlight, and moisture.

Additionally, we can help you choose what to use to waterproof a roof, how to waterproof a terrace, or which is the best waterproofing product for exterior walls for your specific needs. Visit Brikum, choose the product that best suits your project, and say goodbye to dampness and leaks forever.