Backed PVC Waterproof Membrane | Non-woven Fabric Backed, Fully Adhered, Ideal for Concrete and Old Roof Renovation
1. Product Overview
Type L backed PVC sheet pairs solid homogeneous PVC top with polyester nonwoven fabric bonded onto its bottom through thermal compound processing. We produce all items following GB 12952-2011, and can supply full FM full-adhesion test reports plus factory inspection paperwork for every order. Raw stock uses pure virgin PVC mixed with anti-UV additives during one-step extrusion; no halogen or migrating softener gets added, so the product stays eco-friendly and recyclable.
The attached nonwoven base soaks up matching glue thoroughly, locking tightly onto cement mortar and worn asphalt roofing bases. This design rules out mechanical fastening or loose ballast setup entirely, built exclusively for full bonding installation. Its off-white high-reflective finish meets common cool roof specifications. When paired with Homogeneous PVC and Reinforced PVC, the three grades build a full standardized single-ply roof system, widely put into new concrete roof build, outdated asphalt retrofit and lightweight roof jobs with limited load capacity.
2. Product Structure
This sheet comes as two thermally bonded layers: solid homogeneous PVC on top, plus minimum 80g/㎡ polyester nonwoven fabric heat-laminated at bottom. Thermal fusion joins two layers seamlessly with no split or peeling risks in daily use. Anti-UV and anti-ageing additives go into PVC raw mix to sustain steady outdoor performance under long-term exposed conditions. Open porous structure of the nonwoven lets glue sink in completely and anchor firmly onto base surfaces, greatly boosting overall stability of fully stuck roof layers.
3. Technical Parameters
Execution Standard: GB 12952-2011, full test docs and FM full-adhesion certification available upon request
Dimensions: Thickness 1.2mm,1.5mm, custom thickness acceptable; roll width 2.0m, roll length 20m /30m
Temperature tolerance: Remain intact without cracking at -25℃, no sag or deformation at 80℃
Mechanical indicators (test per GB/T 528, GB/T 328.23): Tensile strength ≥10MPa, break elongation ≥500%, puncture resistance ≥200N, zero seepage under 0.3MPa water pressure over 30min
Base bonding index (GB/T 328.20): Nonwoven fabric ≥80g/㎡, peel bonding strength with substrate ≥1.5N/mm
Heat ageing performance: Retain over 90% original mechanical values after continuous 80℃ ageing for 28 days
Service lifespan: Minimum 20 years under regular open-air application environment
4. Core Advantages
Nonwoven backing secures tight bonding to stop blister and layer separation
The bottom textile layer absorbs construction glue uniformly and sticks closely to concrete and aged asphalt. It effectively stops frequent onsite troubles like bubbling, hollow pockets and curled edges, making this variant the go-to material for all full-adhesion roof projects.
Solid PVC surface enables continuous hot air welding for reliable waterproof joints
Entire top PVC layer shares consistent material composition, allowing full hot-air fusion across all overlapping seams. Molten weld merges into surrounding sheet with no hidden gaps that cause water leak, keeping roof intact against rainfall for decades of open-air usage.
Good chemical and weather adaptability fits varied aged base conditions
Formulated from stable pure PVC feedstock, the sheet stands erosion from acid, alkali and various oil-based chemicals. It bonds well onto worn modified asphalt and aged concrete, permitting direct overlay without stripping old roof layers, cutting down construction cost and working period for renovation works.
High-reflective off-white surface saves energy with no extra top coating needed
Light-toned reflective finish lowers rooftop heat gain and reduces overall building power consumption as per cool roof criteria. Built-in UV and ozone resistant components remove need for extra surface protection; the sheet resists chalking and cracking under long-term outdoor exposure and keeps later maintenance costs low.
Three-grade matching forms complete unified single-ply roof system
We configure three PVC grades for differentiated construction zones: Type L for large-area full bonding sections, Type H plain PVC for detailed flashings at corners and pipe penetrations, Type P fiberglass-reinforced PVC for high-wind large-span roof areas. Matching these three grades unifies construction standards and improves whole-project waterproof reliability.
5. Application Scenarios
Full-bond waterproof for concrete flat roofs: New poured concrete flat roof, exposed basement top slab and concrete roof decks of public buildings.
Old asphalt roof refurbishment: Direct overlay above existing SBS and aged asphalt roof, skip full old layer removal to finish renovation fast and cost-efficiently.
Low-load restricted roof build: Lightweight roof structures unable to bear screw fasteners or piled ballast stones.
Small & medium auxiliary building roofs: Open-air fully bonded waterproof for building podiums, pump houses and assorted supporting outbuildings.
6. Standard Construction Guidelines
Base prep work: Make substrate solid, flat, dry and free of sharp spikes, grease and leftover dirt. Fully cure asphalt base first; keep concrete moisture below 9% before laying sheets.
Working environment rules: Install when ambient temperature sits above 5℃; warm up base and membrane in cold weather. Pause all outdoor construction during rain, snow, strong wind or heavy fog.
Overlap & welding rules: Leave ≥80mm longitudinal overlap, ≥120mm transverse overlap. Reference welding temperature ranges 480–580℃; final heat setting follows on-site trial weld and peel test results. Roll fresh weld immediately to squeeze trapped air and secure full material fusion.
Full adhesion operation: Spread designated PVC glue evenly with tooth-shaped scraper at 0.5–0.8kg per square meter rate. Keep nonwoven backside clean and grease-free before rolling and pressing sheet tight onto base.
Detail reinforcement steps: Prior to large-scale Type L laying, fix 150–300mm wide Type H strips around inside/outside corners, pipe roots and equipment footings to form closed waterproof perimeter.
Edge finishing & finished roof protection: Fasten edge trim with metal fixings then seal gaps with dedicated PVC sealant. Ban foot traffic and material stacking on finished roof within 24 hours to guard welded seams and intact waterproof layers.
7. Product Summary
Produced following GB 12952-2011, Type L PVC gains outstanding full-bond performance thanks to its nonwoven backing layout, targeted at concrete roof build and aged asphalt retrofit projects. Matched with Type H detail-use sheets, it builds a mature full-adhesion single-ply roof system, a practical waterproof pick for low-load structures and all kinds of roof renewal projects.
