Owl VCL & Carrier Membrane

Description

Owl VCL & Carrier Membrane: Vapour Control Layer for Lava 20 Roof Systems

Owl VCL & Carrier Membrane is a self-adhesive vapour control layer made from elastomeric SBS-modified bitumen, reinforced with glassfibre and faced with aluminium foil. It is designed for UK roofing contractors, specifiers and builders working on new warm roofs and roof refurbishments. It gives you vapour control and waterproofing in one quick, flame-free layer.

The aluminium facing gives very high resistance to water vapour (Sd > 1,500 m). This helps stop warm, moist air from inside the building reaching the insulation, which reduces the risk of condensation, mould and corrosion within the roof structure.

Key Benefits

• Fast, safe installation: peel-and-stick application with no torch, no hot works and no additional adhesive
• Excellent vapour control: Sd > 1,500 m (μ > 2,680,000) to EN 1931
• Built to last: durable SBS-modified bitumen compound for long-term performance
• Flexible in cold weather: low-temperature flexibility down to -25°C
• Handles movement: accommodates slight substrate movement and acts as a flexible bridge and bond breaker at joints
• Tough on site: resists tearing and stretching under foot traffic during application; the aluminium face resists UV, chemicals and impact
• Lava 20 ready: no primer is needed between the aluminium face and Lava 20
• Temporary weather protection: once installed and sealed, it can be left exposed for a few weeks before Lava 20 is applied

Applications

Use Owl VCL & Carrier Membrane as a vapour control layer beneath insulation in roof build-ups, especially on buildings with high internal vapour levels, such as:

• Factories and industrial units
• Swimming pools
• Sports halls and leisure buildings

It can be incorporated into new warm roofs, or used as a carrier membrane over suitable existing roof decks in refurbishment projects. Its position and application must follow the specified roof design.

Technical Specification

• Chemical base: Elastomeric SBS-modified bitumen
• Reinforcement: Glassfibre
• Upper surface: Aluminium foil
• Lower surface: Removable siliconised film
• Nominal thickness: 0.5 mm
• Mass per unit area: 0.5 kg/m²
• Roll size: 50 m × 1 m (50 m² nominal)
• Water vapour resistance: Sd > 1,500 m
• Tensile strength (MD/CD): 900 / 700 N/50 mm
• Tear resistance, nail shank (MD/CD): 200 / 200 N
• Flow resistance at elevated temperature: ≥ 90°C
• Watertightness: Pass (EN 1928, Methods A & B)
• Shelf life: 12 months from date of production
• Standards: EN 13707 and EN 13970, CE marked

Net coverage depends on the overlaps and detailing required.

Installation Overview

1. Prepare: make sure the substrate is dry, sound and free from oil, dust and contaminants.
2. Prime (VCL use): apply Lava 20 EPDM & TPO Primer (recommended for its slower drying time), Lava 20 Fast Primer or an approved solvent-based bitumen primer. The same options apply over OSB.
3. Lay while tacky: align the roll, then peel back the release film and press the membrane firmly onto the primer while it is still wet or tacky. Do not wait for the primer to dry.
4. Detail and lap: start at the outlet and work uphill, overlapping each section by at least 150 mm (6 in) so water runs over the laps.
5. Finish with Lava 20: apply Lava 20 directly onto the aluminium face; no primer is required.

For other substrates or spray adhesives, contact our technical team before installation. Download the Technical Data Sheet for full instructions.

Storage

Store rolls upright on a flat surface in a dry, shaded area away from UV and heat. Do not stack rolls, and keep the pallet wrapping closed until use.