Thermafleece Breather Membrane

Thermafleece Breather Membrane is a light weight vapour permeable underlay designed for use in floors and walls or on top of insulation as a protective layer.

The material meets EN 13859-1 for pitched roofing and EN 13859-2 for walls. Thermafleece Breather Membrane has good water resistance, high breathability and is lightweight and easy to handle. The membrane is coloured black on one side and grey on the other with no text or images on either side.

Thermafleece Breather Membrane comprises 3 layers; two outer layers composed of a nonwoven polypropylene and an inner breathable microporous film.

Standards
• EN 13859-1 (roofs)
• EN 13859-2 (walls)
• EN 12311-1 (elongation & tensile strength)
• EN12310-1 (tear resistance)
• EN12572 Set C (vapour transmission)
• EN 1928 (water penetration)
• EN1109 (low temperature stability)
• EN 1928 (artificial ageing)

Installation Guidelines for Walls

Fix the membrane to the wall structure; ensure
upper layers overlap lower layers. Work from the
bottom moving upwards and ensuring there are
minimum overlaps of 100 mm on the horizontal
joints. Do not begin a vertical lap joint within
300 mm of a corner, and vertical laps should be
at least 150 mm. Ensure the bottom timber is
also protected by an overlap. Fix at suitable
intervals with galvanised nails, stainless staples
or similar fixings that will be permanent.

Do not leave the membrane unnecessarily exposed to weathering since high winds; excessive UV etc. may cause damage over time. If you are required to leave the membrane exposed for extended periods of time, consider the use of suitable temporary protection materials.

Installation Guidelines for Floors

Thermafleece Breather Membrane is ideal for supporting insulation between suspended floor joists or as a protective layer above insulation installed between floor joists to prevent the accumulation of debris on top of insulation. The membrane can be nailed or stapled to the underside of the floor joist if access permits. Alternatively, the membrane can be installed from above the rafter. For best performance staple the membrane to the lower side of the joist and run the membrane across before stapling to the lower side of the next joist before running over the top of the joist and repeating. Ensure an overlap of at least 100mm between layers of membrane.

Thermafleece breather membrane can also be laid on top of loft insulation to keep the insulation clean and free of debris.

Further Guidance

Always handle carefully to prevent tears and punctures. Repair any damage which does occur with suitable tape. Ensure that sufficient ventilation is incorporated to comply with all relevant building regulations and technical standards. Store all materials in suitable conditions.