Bituminous Membrane

Boz Altinay Construction Industry Inc.

Bituminous membrane is a waterproofing material in roll form with a reinforced carrier structure that provides sealing on surfaces in contact with water.
These membranes, which have a wide range of uses from foundations to roofs, are frequently preferred in professional waterproofing projects with their flexibility, durability, and long-lasting performance.

Where is Bituminous Membrane Used?

Bituminous membranes are widely applied in the following areas to prevent water from damaging the structure:

  • Foundation and curtain wall insulation

  • Terrace and sloped roofs

  • Under-insulation of wet areas (bathrooms, kitchens, etc.)

  • Car park and basement floors

  • Surfaces where water reaches horizontally or vertically (slopes, curtain walls)

  • Tunnel and infrastructure projects

  • Irrigation channels, water tanks and pool edges

What are the Types of Bituminous Membrane?

Bituminous membranes vary according to the additives and carrier reinforcements used:

1. APP Modified (Atactic Polypropylene) Bituminous Membrane

  • Provides high UV resistance in hot climates.

  • High thermal expansion resistance.

  • It is generally preferred with a 4 mm thickness and a polyester carrier.

2. SBS Additive (Styrene Butadiene Styrene) Bituminous Membrane

  • It does not crack in cold weather conditions and has high flexibility.

  • It offers ease of application even at low temperatures.

  • It is frequently used in tunnels and foundations.

3. Mineral Coated (Sandy or Stone) Bituminous Membrane

  • It is covered with mineral stones that provide UV resistance on the upper surface.

  • It is generally used as the final coat.

  • It provides visual and physical strength.

How is Bituminous Membrane Application Done?

  1. Surface Preparation:
    The concrete surface to be applied must be clean, dry and smooth. Primer (bitumen emulsion) is applied if necessary.

  2. Heating and Spreading:
    The membranes are adhered by heating them from the lower surfaces with a special flame torch.

  3. Overlapping the Joints:
    The rolls are applied with an overlap of at least 10 cm and the joints are firmly welded.

  4. Protection Layers:
    In underground or open areas, protection with geotextile felt, drainage board, or screed is recommended.

Advantages of Bituminous Membrane

✔ 100% Waterproof: Completely prevents water ingress into the structure, preventing moisture, mold, and frost damage.
✔ High UV and Heat Resistance: Long-term resistance to sunlight and outdoor weather conditions.
✔ Flexible and Adaptable: Does not crack against structural movements and maintains its flexibility for a long time.
✔ Ease of Application