Vapour control layers play an important role in flat roof construction by helping to manage the movement of moisture vapour within the roof build-up. Positioned on the warm side of the insulation, they help reduce the risk of condensation in the roof build-up and contribute to the long-term performance of the roofing system. Sika's range of SikaShield® vapour control layers includes torch-applied and self-adhesive solutions designed for compatibility with bituminous roofing systems. Reinforced for durability and suitable for a variety of deck types, these membranes form part of a complete roof build-up alongside insulation and waterproofing layers.
Comparison of Sika's Bitumen Vapour Control Layers
SikaShield® VB P41 S 3 mm is a torch-applied bituminous air and vapour control layer featuring an aluminium foil core, reinforced with a dimensionally stable non-woven polyester inlay and surfaced on top with sand. Designed to provide a high-performance vapour barrier while also offering enhanced watertightness.
Key features:
- Aluminium foil core for vapour control performance
- Torch-applied installation
- High elongation and flexible at cold temperatures
- Good resistance to tensile, tear and shear forces
- Suitable for non-combustible substrates such as concrete or metal decks
SikaShield® VB P42 S 3 mm is a torch-applied bituminous vapour control layer reinforced with glass fibre reinforcement and a dimensionally stable non-woven polyester inlay and its top surface covered with sand. Designed for use within bituminous roof systems where a durable vapour control layer is required.
Key features:
- Torch-applied installation
- FM Approved
- Durable
- High resistance to water vapour movement
- Vapour diffuser and waterproofing incorporated in the same membrane
- Good resistance to tensile, tear and shear forces
- Suitable for high humidity roof spaces
- Used as vapour control layer and as a base sheet in multi-layer systems
SikaShield® VB E71 PE SA 2,4 mm is a self-adhesive air and vapour control layer designed for use where torch-free installation is preferred or required. The self-adhesive application helps simplify installation while maintaining compatibility with bituminous roofing systems.
Key features:
- Reinforced with aluminium foil
- Self-adhesive installation
- Suitable for Safe2Torch applications
- Flexible even at very cold temperatures
- High resistance to water vapour diffusion
- Good watertightness
- Suitable for concrete, metal and timber roof decks
Our Range of Bitumen Vapour Control Layers
FAQ
A bitumen vapour control layer is a bitumen based membrane installed within a roofing buildup to prevent warm, moist air from inside a building from reaching colder layers, where it could condense and cause damage.
Bitumen vapour control layers are used in flat roof constructions beneath insulation and waterproofing membranes.
Bitumen vapour control layers play a critical role in flat roof construction by preventing warm, moist air from inside the building from reaching colder parts of the roof buildup. Without a vapour control layer, this moisture can condense within the insulation or structure, leading to reduced thermal performance, mould growth and long-term damage.
Sika offers torch-applied and self-adhesive bitumen vapour control membranes. Some membranes feature aluminium reinforcement for enhanced water vapour resistance.
Sika bitumen vapour control layers can be applied using torch-applied or self-adhesive methods.
Consider factors such as internal humidity, insulation type and roof buildup. Contact a member of our team here for technical support to ensure the correct specification for your project.
Sika bitumen vapour control membranes are fully compatible with the SikaShield® bituminous membranes systems.
