JC/T 2291-2014 Standard and Download
How the Chinese industry standard for water-resistive and vapour-permeable underlays is used in specification, testing and acceptance.
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Standards & Reports
Technical documents
JC/T 2291-2014 PDF
Chinese industry standard for water-resistive and vapour-permeable underlays.
EN 13501-1 Test Report PDF
Report THJS26040785021EN for the submitted membrane samples and stated test conditions.
Technical Articles
Articles and field guidance
How Waterproof Breathable Membranes Work
Why a functional membrane can resist liquid water while permitting water vapour diffusion through a roof or wall assembly.
Read technical analysisEN 13501-1 Fire Classification Report
Scope and limitations of Kedebon report THJS26040785021EN for waterproof breathable and vapour barrier membrane samples.
Read technical analysisPassive-House Membranes and Airtightness
Detailing self-adhesive exterior and interior membranes at windows, services and roof-wall junctions.
Read technical analysisMetal Roof Moisture-Control Analysis
Coordinating exterior drainage and drying with interior vapour control in insulated steel roof assemblies.
Read technical analysisWall and Timber Envelope Membrane Analysis
Weather-resistive barriers, drainage cavities and air-control layers for timber and lightweight wall systems.
Read technical analysisLight-Steel Wall Membrane Installation
Detailed installation sequence with Australian and New Zealand compliance references for low-rise light-steel construction.
Read technical analysisInterpreting Membrane Performance Data
A system-based reading of watertightness, vapour transmission, tensile, tear, ageing and low-temperature results.
Read technical analysisMembrane Installation and Acceptance Guide
Field inspection of laps, openings, penetrations, terminations, repairs and concealed-work records.
Read technical analysisOverlap and Tape-Sealing Guide
How slope, drainage, wind, substrate and installation conditions affect membrane laps and tape joints.
Read technical analysisMetal Roof Condensation Troubleshooting
A layer-by-layer method for distinguishing external leakage from internally generated condensation.
Read technical analysisWhere to Place a Vapour Barrier
Why the warm-side rule requires climate, operating condition and hygrothermal verification.
Read technical analysisRisks of Reverse Membrane Installation
Checking functional faces, drainage laps, adhesive faces and exposure before covering the membrane.
Read technical analysisFastener and Penetration Sealing
Restoring membrane continuity around screws, brackets, pipes and irregular service penetrations.
Read technical analysisWindow-Opening Membrane Flashing
Sill-first flashing and integration of side and head details with the wall weather barrier.
Read technical analysisStorage, Transport and Ageing Control
Protecting membrane rolls from UV, rain, crushing, contamination and excessive exposure before enclosure.
Read technical analysisMaterial Batch and Arrival Inspection
Traceable acceptance of product identity, dimensions, batch labels, reports, retained samples and installed areas.
Read technical analysisMetal Roof Underlay and Wind-Uplift Control
Wind zones, temporary exposure, restraint and continuous load paths for large steel roofs.
Read technical analysisGutter, Ridge and Parapet Membrane Details
Maintaining drainage and vapour-control continuity at critical metal-roof terminations.
Read technical analysisBalancing Vapour Permeance and Watertightness
Selecting an exterior membrane by assembly drying needs, rain exposure, mechanical demands and detailing quality.
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