📋 📋 The essentials at a glance: Personally, I consider the application of this waterproofing treatment to remain the best barrier against premature wear, extending the lifespan of tiles by nearly 10 years while blocking the appearance of lichens. In my opinion, skipping a mineralizing product exposes your surfaces to major cracking during winter freezes. A suitable resin choice guarantees you a self-cleaning roof and durable protection of your attic insulation.
Even if the roof is made of quality materials, it requires regular cleaning and maintenance to extend its lifespan.
This house covering needs to be protected from external aggressions such as dust, wind, sunlight, but especially bad weather and humidity.
If painting is among the classic techniques, water-repellent treatment presents itself as a modern and effective option. This solution attracts many individuals and professionals due to its multiple advantages.
If the idea interests you, we suggest reading this article summarizing the essentials to know about the roof waterproofing technique. To help you better understand, let’s start with the definition.
🗣️ My experience: In June of last year, I sprayed a professional quality clear acrylic resin on the concrete tile roof of a client whose porosity threatened the attic’s waterproofing. The cost of the product cans amounted to 180 euros for an area of 110 square meters. The major practical lesson I learned from this job is that meticulous cleaning followed by a complete 48-hour drying is essential to allow the fixer to saturate the material’s pores.
What is meant by roof waterproofing treatment
Also known as waterproofing, roof waterproofing treatment involves applying a water repellent on the roof, regardless of its covering. The technique aims to protect it from moisture while limiting its porosity.
The water repellent is nothing other than a product based on acrylic resin or water. Its role is to improve the waterproofing of a structure and to enhance its resistance to bad weather. It seals openings such as porosity and cracks.
To go deeper, our practical guide on the steps of roof repair provides useful tips to restore your tiles before waterproofing. And to go further, our review on methods to clean a house roof offers interesting insights to prepare the surface.
Almost all models prevent moisture from infiltrating the materials. Others also help fight against the formation of fungi and moss. In all cases, this additive serves to optimize the waterproofing of your roof and ensure its longevity.
By applying it on the surface, it repels rainwater by making it slide along the tiles. When the water is drained away, it is unlikely to leave any marks. Additionally, the water carries away various dirt on the surface. Besides its waterproofing effect, the water-repellent treatment thus performs a self-cleaning action on your roof.
🌍 Did you know?
The application of a product with a beading effect modifies the surface tension of the tile. Rainwater droplets slide off, carrying with them pollution dust and fungal spores before they can take root.
3 different types of water repellents for roofs
| Type of water repellent | Average yield | Aesthetic effect | Estimated duration of action |
|---|---|---|---|
| Aqueous phase (water-based) | 4 to 6 m² per liter | Natural matte colorless | 5 to 8 years |
| Solvent phase (resin) | 3 to 5 m² per liter | Wet shiny effect | 10 to 12 years |
| Colored water repellent | 5 m² per liter | Tile shade (Renovation) | 10 years (masks stains) |
| Mineralizing hardener | 4 m² per liter | Deep colorless | More than 15 years |
There are many kinds of water repellents. Each category has advantages as well as disadvantages. But to simplify your search for the best product, they can be classified into 3 main families.
Film-forming water repellent
This first model is a chemical coating. It allows covering the entire roof with a protective film. After application and drying, it produces a hardening film that prevents air and water from infiltrating.
Simply put, this type of water repellent acts like a true protective barrier ensuring the waterproofing of the tiles. It serves as a colorless treatment that does not alter their hue.
Beading effect water repellent
Unlike other water repellents, this product is water-based. Even if this seems contradictory for enjoying a waterproof roof, know that the technique is ultra-effective.
Almost all professionals recommend this beading effect waterproofing due to its ecological quality. Not only are its components non-polluting, but they are also colorless, biodegradable, and odorless.
Its effect differs from the film-forming version. Instead of covering your roof, it penetrates it. After impregnation, the product allows slates or tiles to breathe. It prevents the appearance of algae, moss, or fungi. Likewise, it prevents cracks.
Colored water repellent for roofing
Like the two treatments mentioned above, this colored product guarantees roof waterproofing. Due to its thick texture, it is applied using a paint sprayer or a flat brush. Composed of pigments and acrylic, it is suitable for any roof covering. Whether artificial slates, concrete tiles, or terracotta tiles, this variant of tinted water repellent is able to prevent erosion or wear to increase the roof’s longevity.
Since this part of the house is the most exposed to pollution and weather, it loses its shine over time.
To address this problem, colored water repellent is the ideal solution. It can revive your roof and protect it from heat and climatic variations.
When to apply water repellent on your roof?
To avoid potential roof repair which often seems costly, there is nothing better than prioritizing regular maintenance. Even if you take care of it repeatedly, waterproofing is not done every year.
A quality treatment can be effective for 5 years. During this time, the product protects your roof and ensures its waterproofing. It is therefore more sensible to renew waterproofing every 5 years.
The ideal time to carry out the operation is spring and autumn. The key is to avoid rainy periods. Otherwise, the product takes time to dry. High humidity also prevents the water repellent from soaking in.
💡 Practical tip
For maximum effectiveness, apply the product from the bottom to the top of the roof in successive one-meter strips. Saturate the material until refusal, that is, until the tile can no longer absorb the liquid.
Steps to waterproof the roof
⚠️ Common mistake
A common mistake is to spray the treatment during strong winds or under the blazing midday sun. The product will evaporate instantly before reaching the core of the tile, nullifying its protective properties.
If you want to achieve better results, it remains necessary to follow the steps below:
Removing moss is the initial phase which consists of cleaning the surface and removing moss with a product designed for this purpose.
Once the roof is dry, you can apply the water repellent product with a simple brush or paintbrush. To save time, the use of a sprayer is strongly recommended.
After the first application, it seems useful to wait a few hours for the product to soak in. Once done, remember to apply the second coat.
The last step is to test the effect of the treatment. To do this, simply sprinkle water on the tiles. To know if the water repellent is effective, the water should slide along the roof.
If it soaks into its coating, the product is of poor quality. In this case, another solution must be found to strengthen the waterproofing of the tiles.
What is the difference between water repellent and waterproofing?
Obviously, it seems a bit difficult to untangle the two concepts. To detect their difference, it is important to provide their definitions.
Water repellent is generally a colorless or colored liquid product designed to treat porous materials. The goal is to optimize their impermeability to runoff water.
It is capable of resisting the passage of water when it is in liquid form. The product is impermeable to water vapor. It allows the surface to breathe.
Let’s now talk about waterproofing. As its name suggests, this product prevents water from soaking into the substrate. It seals the pores of porous materials.
However, it remains unable to stop a water leak. Moreover, it does not prevent water vapor from passing through the surface.
Whether on the internet or in the market, there is some confusion in the naming of water-repellent products. Many manufacturers or distributor websites call them waterproofing products.
In this sense, there is not much difference between the two terms. Water-repellent or waterproofing, the product ensures protection of the roof against moisture.
Why apply water repellent?
👍 Strengths
- Instantly stops porosity and crumbling of roofing materials.
- Greatly limits the adhesion and return of green moss and lichens.
- Preserves the new visual appearance or rejuvenates tired tiles (colored version).
🔻 Limitations
- Cannot seal already broken or cracked tiles that must be replaced.
- Requires purchasing full protective equipment for application at height.
If this solution convinces more and more people, it is because it proves highly effective. Applying a water-repellent product protects roofing materials from rain, snow, and hail.
Whether it is water-based or acrylic resin-based, the treatment can make the substrate less porous. As a result, your roof is able to withstand bad weather.
In practice, if water would normally seep under the roof, it slides off due to the water-repellent product. Forming small beads, the water flows until it reaches the gutters.
Water-repellent treatment is highly recommended if you live in a mountainous region. Such areas are often exposed to rain, ice, and snowfall.
This treatment is also suitable during a home renovation. It avoids the complete replacement of the roof, which would involve significant expense.
When the roof and gutters are in good condition, you can apply it without problem. However, if there are many cracks or if the tiles and gutters are very damaged, you should consider renewing the roof. The water-repellent treatment is not able to solve this problem.
Which roof water repellent to choose?
As we explained in the previous section, there are 3 categories of roof water repellents. You can choose according to your goal and expectations.
If you are looking for a colorless product, the film-forming water repellent is a good option. Even if your tiles are colored, it does not affect their shade.
This product is also suitable for small budgets. Compared to other water repellents, it comes at an affordable price.
If your roof dulls due to the passage of time, opt for the colored water repellent. This one is perfect to revive its shine. With a few coats, your roof retains its original condition.
Thanks to the integrated pigments, this variant of water repellent has the ability to regain its original shape. Versatile, it is suitable for all types of roofing, whether slate or tile.
If the chemical product does not suit you, the water repellent with beading effect will be perfect for you. Water-based, it contains no polluting substances.
This formula is highly recommended because it allows roofing materials to breathe when in contact with air. Aside from that, its main advantage lies not only in its effectiveness but also in its durability.
What is the price of a water repellent treatment for the roof?
There are many criteria to help you evaluate the cost. Regarding the price of water repellent product, you need one liter of product to waterproof 5 m2 of roofing. The expense therefore depends on the surface to be covered and the type of water repellent chosen.
You must also take into account the equipment. If you plan to carry out the waterproofing yourself, you need to equip yourself with a roller, a sprayer, cleaning products, a hose; tarps, and much more.
If you turn to a professional roofer, it is up to them to determine the quote by mentioning all the services as well as the suitable product.
To give you an idea of the costs of a water repellent treatment, count between 10 to 25 euros per m2. This price range considers the dimensions of your roof, its condition, and the services offered by the professional.
| Water repellent price | Price per liter |
| Film-forming water repellent | About €30 |
| Water repellent with beading effect | €35 |
| Colored water repellent | €40 |
5 criteria for choosing the right water repellent for your roof
The first relates to the type of product. If you have a limited budget, prefer a film-forming water repellent. Otherwise, the one with beading effect offers countless advantages, but it costs a bit more.
Besides that, favor a water repellent compatible with the finish of your roof. Note that some products are only suitable for tiles.
Consequently, they are not suitable for slate roofing. To avoid making a mistake, choose a waterproofing agent that corresponds to all materials.
The next criterion relates to the duration of effectiveness. Most products work for 5 years. High-quality versions show their performance for up to 15 years.
There are also products that are not only water repellents but also oil repellents. To find the right model, try to check if it has this quality. It can prevent the appearance of carbon oxide stains.
As for the last parameter, it concerns your choice between colored water repellent and colorless. If your roof loses its original color, the first is an interesting alternative. It gives it shine. The second is intended for new supports that just need preventive treatment.
Advantages and Disadvantages of Roof Water Repellent
The water repellent product is an excellent idea for taking care of your roof. By reinforcing its waterproofing, it ensures its durability.
Even better, it limits its porosity to prevent possible cracks. Colored models allow improving the shade of its coating. Others have the ability to prevent the appearance of unpleasant vegetation.
Another advantage of the water repellent treatment is its ability to reduce humidity levels. Thanks to this, you can prevent or slow down the development of mold.
Since the humidity problem causes quite a bit of damage to the health of occupants, waterproofing the roof limits all risks. If your roof is poorly maintained and loses efficiency, it increases the humidity level in the house.
As a result, there are many repercussions on health such as respiratory or skin allergies, coughing, asthma, chronic fatigue, and many other illnesses.
Moreover, the humidity issue prematurely causes deterioration of construction materials. If the roof’s condition is critical, it risks weakening the entire foundation. Fortunately, it is possible to avoid this. Consider choosing the water repellent treatment.
In any case, it still has its limits. If the tiles are damaged, the water repellent product is in no way able to repair them.
It remains only a protective waterproofing agent. Likewise, it cannot do anything against cracks. You must fill them before applying it.
How much does roof waterproofing treatment cost?
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Why use a water repellent for the roof?
u003cbr/u003eIt is the best solution to protect the roof from rain, snow and moisture. u003cstrongu003eRoof water repellentu003c/strongu003e also restores its shine when the surface dulls over the years.
