Cromar Vent 3 Pro 165gsm Breathable Membrane
The Cromar Vent 3 Pro 165gsm Breathable Membrane is a premium triple-layer roofing underlay designed for both cold and warm pitched roofs. Made from high-quality spun-bonded polypropylene with a micro-porous film, it provides excellent moisture permeability while remaining water-resistant, ensuring your roof structure stays dry and protected. Suitable for both fully supported and unsupported tiled or slated roofs, Vent 3 Pro is the ideal solution for new builds, refurbishments, and ventilated or unventilated roof systems.
Reliable Weather Protection
Vent 3 Pro acts as a secondary barrier beneath tiles and slates, offering robust protection against wind-driven rain while allowing moisture vapour to escape. This reduces the risk of condensation, prolongs roof life, and enhances overall durability. Its tensile strength and water resistance make it an ideal choice for a wide range of pitched roof applications.
Quality Material & Performance
Constructed from spunbonded polypropylene, the membrane is lightweight, flexible, and easy to install. Its triple-layer design ensures superior tear resistance and reliable performance even in challenging weather conditions. The membrane is BBA certified, CE and UKCA marked, and conforms to NHBC guidelines as well as BS 5250:2021 for moisture management, giving you confidence in both compliance and performance.
Packaging & Handling
Available in 1m x 50m and 1.5m x 50m rolls, packaged in pallets of 56 and 48 rolls respectively.
For safe handling, rolls should be lifted, not dragged, and stored upright on a dry surface.
Avoid prolonged exposure to direct sunlight during storage to prevent damage.
Product Details
Brand: Cromar
Weight: 165gsm
Material: Spunbonded polypropylene with micro-porous film
Roof Types: Cold and warm pitched roofs
Applications: Fully supported or unsupported tiled and slated roofs
Compliance: BBA certified, CE & UKCA marked, NHBC approved, BS 5250:2021
Frequently Asked Questions
1. What is Vent 3 Pro used for?
The **Vent 3 Pro membrane** acts as a breathable roofing underlay, providing secondary weather protection under tiles or slates while allowing moisture vapour to escape, reducing condensation risk.
2. Can it be used on all pitched roofs?
Yes. It is suitable for both **cold and warm pitched roofs**, and works with **fully supported or unsupported** tiled and slated roofs.
3. Is the membrane compliant with building standards?
Absolutely. Vent 3 Pro is **BBA certified**, **CE & UKCA marked**, **NHBC approved**, and meets **BS 5250:2021** standards for moisture control, making it suitable for UK and European construction projects.
4. How should I store and handle the rolls?
Rolls should be **lifted, not dragged**, and stored upright on a dry surface. Avoid exposure to direct sunlight during storage to maintain product integrity.
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