Bitumen Felt vs Liquid Membrane for Flat Roof Waterproofing

bitumen felt

Choosing the Right Waterproofing Solution: Bitumen-Polymer Membranes vs. Liquid Membranes

Nowadays, when the need arises to waterproof a flat roof, there are various innovative liquid waterproofing products available on the market. These can be solvent-free or water-based, made with exclusive selected resins. Additionally, there are high-performance bitumen-polymer membranes that offer effective waterproofing solutions.

Bitumen-polymer membranes and liquid membranes are both used for a wide range of applications, including roof protection, waterproofing of terraces, ground walls, sanitary rooms, parking lots, and civil and industrial surfaces. The primary goal of these waterproofing systems is to create an effective barrier against water and rising damp.

These waterproofing solutions can also be used to maintain and restructure old waterproofing layers and structures, which may have deteriorated over time due to the effects of weather, atmospheric agents, and pollution, particularly in the case of roofs and outdoor areas.

Before choosing the appropriate waterproofing product for a specific situation, especially when conducting renovation or maintenance work, it is crucial to carefully analyze the current state of the roof. This assessment helps determine the most suitable solution.

  1. Geometrically Complex Surfaces

A flat roof does not necessarily mean completely smooth and uninterrupted surfaces. There may be various elements present, such as skylights, antennas, pipes, aerators, and other emerging objects, which can pose challenges for effective waterproofing.

Due to the nature of liquid membranes, they can be easily applied with a roller or brush, allowing access to every point of the surface, even in areas with complex geometry.

Compared to a polymer-bitumen membrane, a liquid membrane is better suited for handling irregular roof surfaces. Cutting and shaping a bituminous membrane to fit around obstacles can increase the risk of discontinuities in the waterproofing layer, potentially leading to water infiltration issues.

However, if the roof surface is linear and unobstructed, the installation of a polymer-bitumen membrane can be just as effective as a liquid membrane. The choice ultimately depends on the specific characteristics of the roof and the accessibility of the areas that require waterproofing.

  1. Maintenance of Old Bituminous Felts

When it comes to renovation projects, the choice of the waterproofing product must be made only after a meticulous analysis and assessment of the existing roof surface's condition.

Designers and installers must focus their attention on several key factors, such as:

- Old, deteriorated membranes

- Loss of adhesion to the support caused by the action of atmospheric agents

- Structural problems in "delicate" areas of the roof, like around drains, ducts, joints, and railings

If the roof has large, unobstructed surfaces, the application of polymer-bitumen membranes can be a viable option, even if overlaying the existing membrane (provided that it is in good condition). However, to ensure perfect waterproofing in this case, it is necessary to apply a water-based bituminous adhesive. This will help facilitate the proper adhesion between the new and old membranes, mitigating the risks caused by potential differential movements.

This technical solution allows for the installation without the use of open flames. If the surface is a screed, the bituminous membrane is the ideal solution. However, if the surface is irregular, it is better to use a liquid membrane, even on top of the old waterproofing cover.

The key is to thoroughly assess the existing roof conditions before determining the most appropriate waterproofing solution for the renovation project.

  1. Flat Roofs vs. Terraces

In the past, flat roofs were often waterproofed and then largely forgotten, aside from occasional maintenance work. However, in the modern era, it has become common to transform these types of roofs into usable terraces.

This transition can create problems for the existing waterproofing, as granular bitumen felts may not be suitable for regular foot traffic without compromising their waterproofing performance.

Fortunately, modern technology offers effective solutions in the form of highly resistant liquid waterproofing products. These innovative liquid membranes can be applied in a wide range of weather conditions, from 0 to 45 Celsius. They can be used on concrete screeds, even if the substrate is not completely cured or is damp.

These liquid membranes are formulated with special resins and do not contain water or solvents. They can withstand up to 4 bars of counter-pressure and are resistant to potential damage from foot traffic, placement of furniture, and other uses associated with terrace areas. The drying times of these liquid membranes are also very fast.

Another key advantage is that these liquid waterproofing products can be applied directly over existing modified bitumen felts, including granular ones. This makes them a versatile option for converting flat roofs into functional terraces without compromising the underlying waterproofing system.

  1. When the Torch Cannot Be Used

In some situations, the installation of bitumen-modified felts cannot be done using the traditional torch method. This may occur in areas where the use of open flames is forbidden, or when the surface is made up of materials that are sensitive to heat, such as wooden elements.

It can also happen that the safety rules on a specific construction site prevent the use of a gas tank for torch-applied membrane installation.

The adhesive polymer-bitumen membranes are also known as "cold systems," even though hot-air appliances and other specialized equipment are still used to ensure proper installation and the tightness of the side and head joints.

This type of product, which guarantees excellent adhesion to the substrate and is relatively easy to install, is recommended for very regular floors with little interference or surface irregularities. Additionally, when installing adhesive membranes along vertical walls, mechanical fixation is required to avoid the risk of membrane slippage.

Modern technologies and application techniques can be helpful in these situations. The new liquid waterproofing membranes, with their versatility and simplicity of application, can be a valid alternative, especially when dealing with existing membranes that already cover the surfaces.

These liquid membrane products are durable and high-performing, resistant to water stagnation and ultraviolet rays. They can be applied on a variety of substrates, including ceramic floors with excess humidity, concrete screeds, tiles, wood, and metal. Importantly, they are ready to use and do not require additional priming or reinforcements.

  1. An Ecological Choice

The use of products with a particular focus on environmental sustainability and human health is increasingly common in the construction industry. Thanks to technological research and innovation, designers and professionals can now make more eco-conscious choices.

Modern waterproofing has evolved towards the concept of integrated "systems" rather than just individual products. These systems are designed to work together seamlessly, offering maximum effectiveness and performance.

This approach has led to the creation of high-performance, thick bituminous membrane solutions that also function as effective vapor barriers and have excellent mechanical strength.

At the same time, liquid waterproofing membranes have undergone innovative developments. The newest liquid membranes are water-based, solvent-free, and formulated with highly selected resins. These advancements allow the products to provide excellent waterproofing performance, resistance to various stresses, and superior protection against UV rays - which can contribute to energy savings in buildings during the hottest months.

In addition to their waterproofing capabilities, these liquid membranes can also protect surfaces and, in some cases, even repair structural anomalies in the substrate.

ATDM Co. is your trusted source for premium Bitumen 60/70 and Bitumen 80/100. We cater to projects of all sizes, offering a variety of packaging options (drums, bags, bulk) to meet your specific needs.

Our Bitumen is manufactured in state-of-the-art facilities using meticulous processes to ensure exceptional performance and durability. We offer three quality grades (premium, second, and third) to match your project requirements.

Why Choose ATDM Co.?

  • Quality assured: Our Bitumen meets international standards, guaranteeing exceptional performance in various applications.
  • Flexible solutions: We offer a diverse range of packaging options and volumes to suit any project size, from small individual needs to large bulk orders.
  • Global reach: We currently supply to the United Arab Emirates (Dubai), Panama, and Singapore, and are dedicated to expanding our reach.
  • Customer-centric: Our commitment to top-notch products and exceptional service has earned us a reputation for reliability and customer satisfaction.
  • Contact ATDM Co. today to discuss your Bitumen needs and discover how we can help your project succeed.

Leave a Reply

Your email address will not be published. Required fields are marked *