Membranes

What Are Membranes?

A membrane in construction is a thin layer of material used to perform specific functions, such as blocking moisture, allowing vapour transfer, or enhancing thermal insulation. These materials can be made from various substances, including plastic, bitumen, and synthetic compounds.

There are different types of membranes for varying applications. As the name would suggest, Damp Proof Membranes (DPMs for short) prevent the passage of moisture from the ground into the building structure - these are generally installed in ground floors on top of PIR Insulation. 

Breather Membranes are installed on roofs and in walls to allow the passage of vapour from inside the building to the outside, while also preventing water ingress from outside.

Types of Membranes

• Damp Proof Membranes (DPMs)
  • Function: Prevent moisture from penetrating the building structure.
  • Material: Often polyethylene.
  • Application: Ground floors, basements, foundations.
• Breather Membranes
  • Function: Allow vapour to escape from the interior while blocking water ingress from the outside.
  • Material: Typically woven fabric or non-woven synthetic materials.
  • Application: The outer side of insulation in roofs, walls, and timber frame buildings.
• Insulation Membranes
  • Function: Improve thermal insulation by reducing heat transfer.
  • Material: Reflective foil or multi-layered composites.
  • Application: Roof spaces, walls, and underfloor areas.

Where are Membranes Used?

Damp Proof Membranes (DPMs)

• Ground Floors: Installed beneath flooring systems to block moisture from rising from the ground.
• Basements: Applied on floors and walls to prevent water ingress from the soil.
• Foundations: Used in the construction of foundation walls to mitigate dampness.

Breather Membranes

• Roofs: Positioned under roofing materials to allow moisture to escape and prevent condensation.
• Walls: Installed in wall cavities to manage vapour and moisture, particularly in timber-frame construction.
• Building Wraps: Used in external wall systems to enhance moisture management.

Insulation Membranes

• Roof Spaces: Installed between rafters or under roof coverings to reduce heat loss.
• Walls: Applied on external surfaces or within wall assemblies to improve thermal performance.
• Underfloor Areas: Used to enhance insulation and prevent heat loss through floors.

Benefits of Membranes

• Moisture Control: Prevents water ingress and manages vapour, protecting building materials from damage.
• Energy Efficiency: Improves thermal insulation and reduces heat loss, contributing to energy savings.
• Structural Integrity: Enhances the durability of construction elements by preventing moisture-related damage.
• Comfort: Helps maintain a stable indoor environment, improving occupant comfort.