Roof waterproofing with mechanically fastened membranes

The most common method of installing TPO membranes is through mechanical fastening. The membrane is mechanically fastened to the roof structure, which can consist of either wooden sheathing, trapezoidal sheets, or a concrete slab. The membrane is generally fastened through the thermal insulation, which requires special fasteners. Overlapping the membranes prevents the penetration of water into the installation. Due to its great compatibility with various materials such as bitumen, the KÖSTER TPO Membrane is suitable for use in the renovation of roof waterproofing systems as well. For instance, the KÖSTER TPO Membrane can be directly fastened to the substructure without having to remove the old waterproofing system as long as the substrate is intact and structural aspects do not indicate otherwise. Mechanical fastening allows for a quick installation and provides a high resistance to wind loads without placing an additional load upon the waterproofing system. Thus, the roof structure is comparatively light in weight. Furthermore, mechanical fastening guarantees that the membrane will not slip, even on pitched roofs. Mechanical fastening even makes a green roof on a pitched roof possible.

Roof waterproofing with bonded membranes

Full surface adhesion to the substrate offers a time-saving installation. The KÖSTER TPO Membrane features a special fleece coating which increases the bonding of the KÖSTER Polyurethane membrane adhesive. This results in a high adhesive strength and creates a perfect bond to the substrate. It is important that the substrate is suitable for a good adhesive bond. If necessary, an adhesive bridge can be applied. In addition, a wind load calculation must be carried out prior to the adhesion of the membrane in order to provide information about the amount of adhesive required and the alignment of the welding seams. The KÖSTER Polyurethane membrane adhesive is applied in strips to the substrate, the fleececoated KÖSTER TPO Membrane is unrolled, and the membrane is firmly pressed onto the substrate using a rubber hand roller. This enables the adhesive to be spread evenly and help achieve uniformity of the bond. When distributing the adhesive care must be taken to ensure that no material is applied to an area that is to be welded to another sheet.

Roof waterproofing with loose-laid membranes (e. g. green roofs)

A quick and secure way to install KÖSTER TPO Membranes is through loose laying with ballast. Ballast can consist of either gravel, paving slabs, or even green roofs. Ballast helps protect the roofing membrane against wind loads and can accommodate a wide range of architectural styles. A special advantage of this installation method is that the roofing membrane does not need to be mechanically fastened to the substrate. Due to the weight of the ballast, higher loads must be taken into consideration in the roof load calculation.

Liquid applied roof waterproofing

Concrete roofs are often difficult to waterproof with membranes due to numerous penetrations and complex geometry. KÖSTER Elastic Roof is a liquid applied elastic waterproofing for roofs. It is UVresistant, white and crack bridging. The product does not contain solvents and allows an easy, seamless application.

KÖSTER Elastic Roof is directly applied onto the prepared concrete substrate by roller or spraying. It has very good adhesion to itself (important for overlapping and easy repair) and even damp substrates.

Absorbent substrates are primed with KÖSTER Polysil TG 500.

Always adhere to the specifications in the respective Technical Guidelines.

Roof waterproofing with cold self-adhesive sealing membranes

Smaller roofs on non residential buildings can quickly and easily be waterproofed with the cold self-adhesive sealing membrane KÖSTER KSK Alu Strong. The clean and dry substrate is primed with KÖSTER KBE Liquid Film.

KÖSTER KSK Alu is applied onto the dry and primed roof area. Membranes have to overlap a min. of 10 cm on each side. Connections, penetrations and overlaps are sealed with KÖSTER KBE Liquid Film.

Always adhere to the specifications in the respective Technical Guidelines.