Reinforced Polythene Building Membranes
High performance vapour barrier for metal profile buildings.

861 Vapour Barrier is a strong reinforced polythene/foil vapour barrier for use on the inner face of insulation in wall and roof construction to prevent warm, moist air from inside the building condensing within the structure. The reinforced construction resists tears and punctures that can quickly compromise the performance of ordinary building films.

Construction

861 Vapour Barrier is a multilayer membrane with aluminium foil and UV stabilised polythene for vapour resistance and a woven polypropylene grid reinforcing to resist tearing and punctures. The aluminium foil is 'buried' within the construction to resist chemical attack. 861 Vapour Barrier is metallic silver in colour and both surfaces have a smooth, bright appearance.

Technical Data

Basis Weight (g/m2)		311 g
Tensile Strength	-MD	7.3 kN/m
	-CD	7.3 kN/m
Nail Tear Resistance	-MD	215 N
	-CD	182 N
MVTR		less than 0.01 g/m2/d
Vapour Resistance		greater than 20,600 MNs/g

Fixing/Sitework

Metal Profiled Sheet Roofs:

The membrane is laid over the liner panel and all seams sealed with a suitable butyl double-sided adhesive tape. It is covered by the insulation, then a breather sheet, and the external roof covering fixed.

Internal Vapour Barrier:

The membrane is fixed over the insulation and fixed to studwork timbers using corrosion resistant staples or nails. All edges should be overlapped 50-100mm and sealed using water-resistant tape. All service entries, holes and tears and perimeter gaps should be sealed using a self-adhesive tape. The internal plasterboard or cladding is then fixed over the barrier.

Availability

Standard Roll Size	2000mm x 50m
Roll Weight	26 kg

All information given in good faith and is believed to be accurate. Technical data is based on laboratory testing and represents average values. Specific lots may vary above or below these values.