PYE PV250S52 AJ-20 SBS bitumen cap sheet — 5.2 mm, 5 m² roll

A bitumen cap sheet is the outer layer of a roof covering, directly exposed to rain, sunlight and changing temperatures. It contributes to the roof’s watertight protection and shields the build-up from its surroundings. This is a practical solution for flat and low-pitched roofs, both on new buildings and during refurbishment. At SteelProfil, we help select a membrane that suits the design and the layers beneath it.

A typical cap sheet has a mineral finish on its upper surface. This protects the bituminous compound from UV radiation and gives the surface its characteristic appearance. The properties of the complete product also depend on its reinforcement, thickness and bitumen type. SBS-modified membranes can retain the flexibility needed to accommodate temperature changes and substrate movement. A correctly selected product can therefore meet the conditions encountered by the covering throughout the seasons.

A key advantage of roll materials is the ability to create a continuous layer that follows the roof’s shape. Correct laps and carefully formed details allow the roof to be sealed around parapets, chimneys and outlets. Depending on the product, the membrane may form the upper layer of a multi-layer system or be approved for a specific single-layer covering. Before purchase, we check its intended use so that the appearance of a roll does not replace the necessary technical information.

Bitumen cap sheets are used on homes, garages, warehouses, workshops, commercial premises and outbuildings. They are also useful when renovating existing bituminous roofs, provided the substrate condition allows the planned refurbishment. Every renovation should begin with an assessment of the existing layers and drainage arrangements. Working outlets and a suitable roof fall help reduce prolonged ponding, improving conditions for the covering as a whole.

The selected membrane must work with the underlay, thermal insulation and installation method. Not every product can be fixed in the same way or laid directly on every substrate. Surface preparation and working conditions also matter. After installation, check the outlets, remove accumulated leaves and inspect critical joints. A simple inspection helps detect damage early, before a small problem becomes an expensive repair inside the building.

When calculating material quantities, we allow for laps and upstands on vertical elements so that the order reflects the actual extent of the covering.

We offer bitumen cap sheets and help select the required underlay and accessories. Availability of a particular variant is confirmed when preparing the quote. The wider project can also be supplied from our broad range of first- and second-grade materials available from stock. Numerous promotions and particularly competitive prices help achieve a watertight roof at a reasonable cost. Contact SteelProfil with the roof area and type of work. We will help establish the membrane quantity and prepare a complete order for the planned date.