Vent 3® Classic is a breathable roof underlay that gives major benefits
over traditional underlays. The Cromar breather felt is made from two high-tensile, spun-bonded
polypropylene layers. This triple-layer, high performance, breathable membrane
is thermally calendared to a micro-porous polypropylene film. Layer one
- waterproof surface Layer two
- breathable waterproof membrane Layer
three - protection from abrasion and damage, giving additional strength This product has the same specifications as the
Vent 3 Light breathable membrane, but the Classic has a heavier GSM at 115,
compared to this Light's 95 GSM.

• Clean and easy to use
• Lightweight and flexible
• Waterproof membrane
• Long-term durability and tensile/tear strength BS 5534:2014 compliant

Application Can be used in supported or unsupported roof systems, regardless of
whether they are tile slate or metal, and in warm and cold roof
applications. Equally effective whether draped unsupported over rafters or laid
directly onto insulation. High vapour permeability High wind uplift resistance