Waterproof Breathable Membrane | Windproof, Vapor Permeable Roof & Wall Membrane
1. Product Overview
This product is also called roof breathing membrane. It is a three-layer composite functional material. It is made of polypropylene non-woven fabric and micropore breathable core film. The two parts are pressed together by hot melting without glue.
This membrane has tiny holes on its surface. It can stop liquid rainwater from passing through. Meanwhile, it lets inner water vapor go out freely. It solves four common building problems: water condensation inside insulation layers, wall mildew, steel structure rust and building dampness.
This product meets building industry standard JC/T 2291-2014. It has good anti-aging performance and strong tear resistance. It works stably in different temperatures. It can prevent wind, water and air leakage well. It can match most waterproof membranes and insulation boards. People use it for building outer structures to improve air tightness and save building energy.
2. Technical Specifications
Executive Standard: JC/T 2291-2014. Complete third-party test reports can be provided.
Basic Weight: 60 g/m², 80 g/m², 100 g/m², 120 g/m². 80 g/m² is the best choice for ordinary construction projects.
Standard Size: Width: 1.5m / 2m; Length: 50m / 100m
Hydrostatic Resistance: ≥1000mm water column. It has great waterproof ability against rainwater.
Water Vapor Transmission Rate: ≥500 g/(m²·24h)
Temperature Resistance: -40℃ ~ 80℃. It keeps stable performance under big temperature changes.
Tensile Strength: Longitudinal ≥250 N/5cm; Transverse ≥200 N/5cm
Service Life: More than 10 years for short-term outdoor exposure; more than 20 years if covered by other building layers
Additional Certification Support
We can provide official test reports from national building material testing institutions. We also offer RoHS and REACH certificates for overseas orders. These documents meet domestic project inspection and global export requirements.
3. Core Product Advantages
Both waterproof and breathable, no inner water condensation
The tiny holes on the membrane are smaller than raindrops but bigger than water vapor. It blocks rain, snow and mist from entering insulation layers. It discharges inner water vapor quickly. It avoids insulation failure, steel rust and wet moldy walls thoroughly.
Windproof and airtight, help save energy
Full laying of this membrane seals gaps between building boards. It stops cold air from entering rooms and stops indoor heat from losing. It cuts down the use of heating and cooling equipment. It fits energy-saving buildings and passive house construction well.
Three-layer integrated structure, no peeling and hard to tear
The middle breathable film is covered by two layers of high-strength non-woven fabric. All layers are bonded by hot melting instead of glue. It will not peel or crack after repeated temperature changes. It resists piercing and bending well, so it fits normal construction site conditions.
Good weather resistance for outdoor construction
We add anti-UV and anti-aging additives during production. It can bear short-term outdoor exposure. It resists sunlight, rain, acid and alkali corrosion. It works well in hot summer areas and extremely cold northern areas.
Easy to construct and compatible with most building materials
The membrane is soft, so workers can cut it freely on site. It supports many fixing ways, including tape bonding, batten fixing and screw fixing. Self-adhesive type is also optional. It can match TPO/PVC waterproof membranes, rock wool boards, XPS boards and metal roof panels to form a complete roof waterproof and insulation system.
4. Application Scenarios
Steel Structure Roof: Lay it above insulation layers to release inner vapor, prevent steel rust and stop insulation materials from absorbing water
Light Steel & Wooden Buildings: Prevent moisture on roofs and walls, protect inner keels from vapor damage
Curtain Wall Projects: Use as inner lining for external curtain walls, balance wall vapor and prevent inner wall dampness
Public Building Roofs: Auxiliary energy-saving breathable material for stadiums, exhibition halls, factories and other large public buildings
Old Roof Renovation: Improve old roof structure, solve hidden condensation and water leakage problems
5. Construction Guidelines
Lap Standard: Longitudinal overlapping width ≥100mm; Transverse overlapping width ≥150mm to ensure tight sealing
Fixing Method: Use battens, waterproof gaskets and screws for mechanical fixing. All fixed points need extra sealing treatment.
Construction Environment: Construction temperature should be higher than 5℃. Do not construct on rainy, snowy, windy or foggy days.
Finished Product Protection: Cover the membrane with insulation layers or main waterproof membranes right after laying. Do not expose it under sunlight for a long time.
6. FAQ
Q1: What is the difference between waterproof breathable membrane and vapor barrier membrane?
A1: Workers lay waterproof breathable membrane outside insulation layers. It lets inner vapor out and blocks rainwater. Workers lay vapor barrier membrane inside insulation layers. It locks indoor vapor inside. Using these two products together can build a complete building moisture-proof system.
Q2: Can this breathable membrane be used for long-term permanent outdoor exposure?
A2: We do not suggest long-term permanent outdoor exposure. It is an auxiliary building material, and it only bears short-term outdoor weather damage during construction. Cover it with insulation layers or main waterproof layers to extend its service life.
Q3: Will the membrane turn hard or crack in cold winter?
A3: No. It keeps soft even at -40℃. It will not become brittle or crack. It is suitable for winter construction in cold northern regions.
7. Product Summary
This three-layer waterproof breathable membrane meets industry standard JC/T 2291-2014. It has four basic functions: waterproof, windproof, airtight and heat insulation. It solves common building problems such as vapor condensation, steel corrosion, reduced insulation performance and wall mildew. It is easy to install and fits most mainstream building materials. It is a necessary auxiliary material for steel structure roofs, curtain walls, light steel villas and all kinds of energy-saving construction projects.
