Stitchbond Nonwoven Fabric for Roof Waterproofing & Membrane Reinforcement

StitchBond Direct manufactures stitchbond nonwoven fabric engineered as a reinforcement carrier for roof waterproofing membranes, cold-applied roofing systems, and liquid waterproofing coatings. Made from 100% polyester (virgin or RPET recycled), this fabric is designed to be saturated with bitumen, acrylic emulsion, polyurethane, or asphalt coatings — delivering the tensile strength, dimensional stability, and elongation performance that waterproofing membranes require.

When embedded into a waterproofing membrane, stitchbond polyester fabric provides a continuous reinforcing layer that bridges cracks, resists thermal movement, and extends the service life of the roof system. The stitch-bonded construction mechanically interlocks fibers, creating a fabric with higher tear strength and better elongation than spunbond or thermal-bonded nonwovens at the same weight.

Available from 40 GSM to 300 GSM, with stitch spacing from 7F to 22F and widths up to 240 cm. Custom slitting, color matching, and heat-setting treatments available for specific waterproofing system requirements.

Technical Specifications

Parameter	Specification
Material	100% polyester (virgin or RPET recycled)
Fabric Construction	Stitchbond (stitch-bonded nonwoven)
Basis Weight	40 GSM – 300 GSM
Stitch Spacing	7F, 9F, 10F, 12F, 14F, 18F, 20F, 22F
Thickness	0.2 mm – 1.5 mm
Width	5 cm – 240 cm (custom slitting available)
Tensile Strength (MD)	85–130 N/5cm at 120 GSM (varies by GSM and stitch pattern)
Elongation at Break	40%–65% (accommodates thermal stress movement)
Thermal Dimensional Stability	<1.5% at 180°C (heat-set treatment available for enhanced stability)
Color	White, black, gray, or custom
Hand Feel	Soft to firm (selectable by GSM and finishing)
Certifications	ISO 9001 · ISO 14001 · EU REACH
MOQ	500 kg (negotiable for trial orders)
Production Capacity	500,000 meters / week

Need a specification outside this range? Send us your target GSM, width, tensile strength requirement, and coating system, and we will confirm feasibility within 24 hours.

Why Stitchbond Nonwoven for Roof Waterproofing?

In roofing applications, the reinforcement fabric must do more than just hold a membrane together. It must:

• Absorb the coating evenly — ensuring full saturation during bitumen impregnation or liquid coating application
• Accommodate thermal movement — expanding and contracting with the roof substrate without cracking or delaminating
• Resist puncture and tear — protecting the waterproofing layer during installation and throughout the roof’s service life
• Maintain dimensional stability — preventing buckling or wrinkling when exposed to hot bitumen or elevated application temperatures

Stitchbond polyester fabric delivers all four requirements. The mechanical stitch-bonding process creates an open, porous structure that saturates rapidly and completely with bitumen, acrylic, or polyurethane coatings. The continuous filament yarns running in the machine direction provide high tensile strength and low elongation under load, while the cross-direction fibers provide flexibility and crack-bridging capability.

Performance Comparison for Roofing Reinforcement

Parameter	Stitchbond Polyester	Spunbond Polyester	Fiberglass Mat
Tensile strength (120 GSM)	85–130 N/5cm	25–55 N/5cm	60–90 N/5cm
Elongation at break	40%–65%	60%–90%	2%–4%
Bitumen saturation	Excellent (open structure)	Moderate	Good
Thermal stress accommodation	Excellent	Good	Poor (brittle)
Puncture resistance	High	Moderate	Low
Handling during installation	Excellent (lay-flat, conformable)	Good	Poor (brittle, irritant)

For cold-process roofing systems — where the reinforcement is embedded into acrylic elastomeric coatings, asphalt emulsions, or solvent-based mastics — stitchbond polyester is widely recognized as one of the strongest yet most flexible fabrics available for adding reinforcement to seams, panel overlaps, splits, joints, cracks, protrusions, and flashings[reference:0].

Roof Waterproofing Applications

Application	Recommended GSM	Stitch Spacing	Function
Liquid-applied membrane reinforcement	60–120 GSM	14F–22F	Embedded into liquid waterproof coatings (acrylic, PU, bitumen) to enhance crack-bridging and tensile strength
Bituminous membrane carrier	80–200 GSM	10F–18F	Saturated with bitumen to form the reinforcing base of roofing felt and modified bitumen membranes
Cold-process roof coating reinforcement	70–150 GSM	12F–18F	Used with asphalt emulsion, acrylic elastomeric coatings, and solvent-based mastics for roof restoration
Roof repair & flashing fabric	60–100 GSM	18F–22F	Reinforcement over cracks, seams, joints, and flashings; bridges splits and gaps
Green roof drainage layer	100–200 GSM	14F–18F	Dimensional stability and tear resistance for green roof construction layers
Roof underlayment base	50–100 GSM	18F–22F	Base layer for roof underlayment systems; provides strength and moisture management

Coating System Compatibility

Our stitchbond polyester fabric is compatible with all major roofing and waterproofing coating systems:

Coating Type	Typical Application	Recommended Fabric GSM
Acrylic elastomeric coatings	Roof restoration, reflective roof coatings	60–120 GSM
Asphalt emulsions	Cold-process built-up roofing, roof maintenance	70–150 GSM
Polyurethane (PU) coatings	Liquid-applied waterproofing, roof decks	60–120 GSM
Bitumen (hot-applied)	Modified bitumen membrane carrier	100–200 GSM
Solvent-based mastics	Roof repair, flashing reinforcement	60–100 GSM

Heat-set treatment is available for applications involving hot bitumen or elevated processing temperatures. This stabilizes the fabric against thermal shrinkage, preventing buckling and surface defects during membrane manufacturing.

Industry Standards

Our stitchbond roofing fabric is tested and supplied to meet the following industry standards:

• ASTM D5726 — Standard Specification for Thermoplastic Fabrics Used in Hot-Applied Roofing and Waterproofing
• ASTM D5665 — Standard Specification for Thermoplastic Fabrics Used in Cold-Applied Roofing and Waterproofing
• ASTM D5733 — Test Method for Tearing Strength of Nonwoven Fabrics (Trapezoid Procedure)
• ISO 9073-3 — Determination of tensile strength and elongation of nonwoven fabrics
• EN 13707 — Flexible sheets for waterproofing: reinforced bitumen sheets for roof waterproofing

Test reports for specific production batches are available on request. We can also arrange third-party testing (SGS, BV, Intertek) for order-specific requirements.

Packaging & Logistics

Item	Standard
Roll length	1,000–2,000 meters per roll (customizable)
Roll core	3-inch paper core or plastic core
Outer wrapping	PE film + woven bag (moisture protection)
Container loading	20–24 rolls per 20′ container (dependent on width/GSM)
Lead time	7–15 days for stock specifications; 15–25 days for custom runs
Shipping terms	FOB Shanghai / Ningbo · CIF · DDP available

Frequently Asked Questions

What GSM stitchbond fabric is used for roof waterproofing?

For liquid-applied membrane reinforcement, 60–120 GSM with 14F–22F stitch spacing is typical. For bitumen membrane carriers, 100–200 GSM with 10F–18F stitch spacing provides the required saturation and strength. For roof repair and flashing applications, 60–100 GSM is commonly used. We can recommend the exact specification based on your coating system and application method.

Is your stitchbond fabric compatible with acrylic and asphalt coatings?

Yes. Our polyester stitchbond fabric is compatible with acrylic elastomeric coatings, asphalt emulsions, polyurethane coatings, solvent-based mastics, and hot-applied bitumen. The open stitch structure ensures rapid and complete saturation with all liquid coating types. For hot bitumen applications, we recommend heat-set treatment to prevent thermal shrinkage.

Can you supply RPET recycled polyester for roofing applications?

Yes. We offer both virgin polyester and 80%–95% recycled polyester (RPET) stitchbond fabric. RPET roofing fabric meets the same tensile strength and dimensional stability specifications as virgin polyester and is available with GRS documentation for sustainability reporting.

Do you offer heat-set treatment for hot bitumen applications?

Yes. Heat-setting is a thermal stabilization process that reduces residual shrinkage in the fabric. For bitumen membrane carriers processed at temperatures above 180°C, heat-set treatment is recommended to prevent buckling and surface defects in the finished membrane.

What widths and roll lengths are available?

Standard widths range from 5 cm to 240 cm. Custom slitting is available for narrow reinforcement strips (e.g., 4-inch flashing tape). Standard roll length is 1,000–2,000 meters, customizable to your production line requirements.

Can you provide technical data sheets and batch test reports?

Yes. We provide TDS for all standard specifications and can supply batch-specific test reports for tensile strength, elongation, and GSM verification. Third-party testing through SGS, BV, or Intertek can be arranged for order-specific compliance requirements.

Do you support OEM/private label for roofing membrane manufacturers?

Yes. We supply roll goods to bitumen membrane manufacturers, liquid waterproofing coating companies, and roof restoration contractors. Custom GSM, width, stitch spacing, color, and heat-set treatment are available. MOQ for custom specifications is typically 1,000–3,000 meters depending on GSM and finish.