Breathable Membranes

The Complete Guide to Breathable Membranes in the UK

Breathable membranes represent an essential component of modern UK roofing systems, offering superior moisture management while maintaining structural integrity. These high-performance materials significantly reduce condensation risks and improve overall building efficiency.

What is a Breathable Membrane?

A breathable membrane is a vapour-permeable, waterproof material used beneath roof tiles or roofing felt. These membranes prevent water ingress while allowing internal moisture to escape, reducing the risk of condensation within the roof space.

Types of Breathable Membranes

• Vapour Permeable Membranes – Allow water vapour transmission while remaining waterproof, protecting against wind-driven rain and reducing condensation risk.

• Air Open Membranes – Provide maximum breathability, suitable for complex roof designs and new build projects. These membranes reduce the need for additional ventilation.

Why Use Breathable Membranes?

• Moisture Control – Prevents condensation within pitched roofs, protecting timber structures from rot and ensuring up to 14 litres of household humidity can escape daily.

• Airtight and Waterproof – Blocks dirt, dust, and external moisture while maintaining airflow.

• Energy Efficiency – Enhances the performance of insulation by keeping it dry, contributing to improved airtightness and reducing energy costs.

• Durable Protection – Suitable for use in extreme weather conditions, providing long-lasting protection.

Key Benefits of Breathable Roofing Membranes

• Water Vapour Permeability – Prevents damp build-up and allows internal moisture to escape.

• Lightweight and Flexible – Easy to handle and install across various roof constructions.

• Weather Protection – Resistant to wind-driven rain and UV stable for extended exposure.

• Range of Sizes and Thicknesses – Available in a wide range of breathable roofing felt and membranes to suit new builds and renovation projects.

Popular Brands and Products

• TLX Breathable Membranes – High-performance membranes designed for modern roof constructions.

• Klober Permo – A leading brand known for breathable roof membranes and felt underlay.

• Cromar Vent 3 – A durable, waterproof membrane suitable for pitched roofs.

Applications of Breathable Membranes

• Pitched Roofs – Installed beneath roofing felt to protect against water vapour and external moisture.

• External Walls – Used as part of timber frame constructions to enhance airtightness.

• New Builds and Renovations – Ideal for both new construction projects and roofing upgrades.

How to Install Breathable Membranes

1. Prepare the Roof Structure – Ensure the roof is clean and dry before installation.

2. Lay the Membrane – Roll out the membrane horizontally, starting from the bottom of the roof.

3. Overlap Each Layer – Allow overlaps of 100mm to ensure full coverage.

4. Seal Joints – Use single-sided tape to secure overlaps and improve airtightness.

5. Fix in Place – Secure the membrane using staples or roofing battens.

Building Regulations and Compliance

• Adherence to UK Standards – Breathable membranes must comply with BS 5250 guidelines to ensure proper moisture management.

• BBA Certification – Look for membranes with British Board of Agrément (BBA) certification.

• NHBC Acceptance – Membranes should meet requirements for NHBC approval.

Conclusion

Breathable membranes are a crucial component for maintaining the integrity of pitched roofs in the UK. By preventing damp and allowing water vapour to escape, these membranes ensure moisture control and enhance the performance of the roofing structure.

Order breathable membranes today to protect your home from moisture damage and improve energy efficiency.