Waterproofing critical joints and movement areas demands a system that performs beyond conventional methods. The right approach secures these vulnerable points against the stresses of structural movement and water ingress. Elastoproof B50 Joint Band provides a highly elastic, integrated bondbreaker system for comprehensive waterproofing and sealing, ensuring long-term protection and stability in demanding environments.
The Elastoproof B50 Joint Band was engineered to detail critical joints, junctions, and areas subject to movement within a waterproofing system. Its innovative design features a central 'Flexible Zone' constructed from a high-strength NBR rubber compound. This allows the band to accommodate movement in longitudinal, lateral, and transverse directions, enabling high elongation, rupture resistance, and up to 100% elastic recovery. It functions as an approved bondbreaker system, seamlessly integrating into Gripset waterproofing membranes to prevent common failure points.
Installing Elastoproof B50 Joint Band involves embedding it into a wet bed of liquid membrane. Measure and cut the band to fit all wall/floor junctions and other critical areas. Apply the first coat of membrane, extending approximately 150mm up walls and onto floors. Then, embed the band into the wet membrane, ensuring the fabric edges are fully wet out and no air bubbles are trapped beneath. The central rubber section of the band remains unbonded to allow for maximum movement. For joins, a minimum 50mm overlap is required. For precise detailing in corners, Elastoproof Prefabricated Corners are available and allow the Joint Band to overlap, avoiding joints in these critical areas.
Elastoproof B50 Joint Band is a key intermediate layer in comprehensive waterproofing systems, particularly for landscaped areas, planters, and garden beds. It is typically applied as the second step in a three-step process. After a suitable primer like Everflex VBS Bitumen Primer has been applied to the substrate, the Elastoproof B50 Joint Band is embedded into the initial wet layer of a Gripset liquid membrane. This sequence ensures a fully integrated and flexible bondbreaker system before the final membrane coats, such as Gripset 2P cementitious membrane, are applied. This positioning is critical for managing movement and reinforcing vulnerable transitions within the full waterproofing build-up.
Elastoproof B50 Joint Band offers a distinct advantage over conventional bond breaking sealants and tapes. While traditional methods rely on separate sealants or adhesive tapes that can fail under stress or require precise, multi-step applications, the B50 Joint Band integrates directly into the liquid membrane. This eliminates the need for their application entirely, simplifying installation and delivering superior durability. Its highly elastic, NBR rubber construction ensures long-term protection at critical joint intersections and movement zones, providing a more reliable and time-efficient solution.
B50 is designed for a maximum starting joint width of 20 mm and accommodates up to 50% movement of that width, with up to 100% elastic recovery in the central zone.
Always embed the fleece edges into a fresh, wet liquid membrane to ensure complete wet-out and adhesion. Apply a second coat to fully encapsulate the band.
Yes. Prefabricated internal (90°) and external (270°) corners are available and recommended to maintain continuity through junctions and reduce on-site fabrication errors.
No. B50 is not intended as an exposed, UV-resistant joint seal. It should be encapsulated within the waterproofing system.
The specified temperature resistance is −20 °C to 90 °C, suitable for a wide range of Australian conditions.
| Application / Use Case | Key Benefit | Primary Trades |
|---|---|---|
| Wall/Floor Junctions | Seamless, flexible transition minimises membrane stress and leaks. | Waterproofers, Tilers |
| Substrate Abutments | Isolates differential movement to protect the membrane. | Waterproofers, Builders |
| Control Joints | Accommodates movement up to 50% of starting joint width. | Waterproofers, Concrete Contractors |
| Movement & Expansion Joints | Decouples structural movement from the membrane layer. | Builders, Waterproofers |
| Corner Intersections (90°/270°) | Factory corners improve continuity and reduce on-site errors. | Waterproofers, Builders |
| Crack Bridging (Non-structural) | Flexible bridging layer to prevent localised leakage. | Remedial Contractors, Waterproofers |
Ensure substrates are clean, dry, sound and smooth; remove contaminants; repair defects; comply with relevant standards for wet areas.
Grind/abrade to remove weak layers and provide a clean surface; vacuum dust before priming.
Apply only when surfaces are dry and between 5 °C and 30 °C (surface temperature).
Pre-cut lengths to suit each run and corner; allow for ≥ 50 mm overlaps at joins; use factory corners where possible.
Cut slightly long for final trim; check alignment over the joint centreline.
If not using factory corners, create a foldable corner by a vertical incision on a short length, then form and bed into wet membrane.
Apply the first coat of liquid membrane in a ~150 mm band centred over the joint. Embed B50 into the fresh membrane and press firmly.
Use a firm brush to wet-out fleece edges and remove trapped air.
Light rolling ensures intimate contact without stressing the central flexible zone.
Overlap band lengths by ≥ 50 mm. Use prefabricated internal/external corners where possible. Apply a second coat to fully encapsulate.
Brush/roll to seal the fleece completely and achieve the membrane’s specified film build.
Observe the membrane manufacturer’s recoat and cure times; protect from traffic until cured.
Wear gloves, long sleeves and safety glasses during cutting/handling and membrane application.
Ensure adequate ventilation when using primers and liquid membranes; follow their SDS.
Store away from ignition sources. Check the selected primer/membrane SDS for flammability and handling advice.
Seek medical attention immediately in cases of serious exposure.
Clean, sound, smooth and dry; remove laitance, release agents and contaminants by mechanical means. Repair voids and non-structural cracks; ensure formed joints are clean and dry.
Apply the membrane manufacturer’s nominated primer, then a 150 mm wet membrane strip. Embed B50 centrally and brush firmly to wet-out fleece.
Use primer specified by the chosen membrane systemRemove loose sand/friable material; make joints flush and repair defects. Ensure junctions are even for uniform band bedding.
Prime as directed. Embed B50 into wet membrane and fully encapsulate with a second coat.
System-compatible masonry primerInstall linings to manufacturer standards; ensure fasteners are flush, joints treated, and surfaces clean and dry.
Follow membrane system guidance. Apply wet membrane (150 mm) and embed B50; overcoat to encapsulate.
Membrane-system primerStructurally sound, firmly fixed sheets with adequate support; sand high spots; remove dust/oils; seal exposed edges where required.
Prime per membrane system; bed B50 into wet membrane and roll/brush to expel air.
System-nominated timber primerDegrease; lightly abrade; remove rust and sharp edges; clean and dry before priming.
Apply the membrane system’s metal/non-porous primer. Embed B50 into wet membrane; fully encapsulate.
Approved non-porous/metal primerEnsure the existing membrane is sound, clean and compatible. Lightly abrade if advised by the membrane manufacturer.
Follow the re-coat/overlay protocol of the selected membrane. Maintain ≥ 50 mm overlaps between band lengths and at corners.
Compatibility primer as directed| Property | Value |
|---|---|
| Base Chemistry | NBR (Acrylonitrile Butadiene Rubber) |
| Carrier Edge | Polyester fleece with lateral flexibility |
| Total Width | 120 mm |
| Thickness | 0.6–0.8 mm |
| Rubber Width | 70 mm span with 20 mm central stretch zone |
| Material Weight | 50 g/m |
| Shore A Hardness | 65 |
| Temperature Resistance | -20°C to 90°C |
| Tensile Strength (Lateral) | >1.0 N/mm² |
| Tensile Strength (Longitudinal) | >7.0 N/mm² |
| Rupture Strain (Lateral) | >208% |
| Rupture Strain (Longitudinal) | >48% |
| Moisture Vapour Transmission Resistance (μ) | 8.4 |
| Equivalent Air Thickness (sd) | 5.0 |
| Water Pressure Resistance | 3 bar |
| Fire Class | B3, F |
| Chemical Resistance | Lactic acid 5%; Acetic acid 5%; Hydrochloric acid 3%; Chloric acid 3%; Sulphuric acid 35%; Citric acid 10%; Potassium hydroxide 20%; Sodium hypochlorite 0.3 g/L; Sea water (sea salt 20 g/L); Lime milk pH 12.5; Sodium hydroxide solution pH 14; Diesel oil; Grease; Oil; Paraffin |
| Maximum Starting Joint Width | 20 mm |
| Movement Capacity | Up to 50% of starting joint width |
| Standards Compliance | AS 3740 |
| Packaging Options | 120 mm × 50 m roll; 120 mm × 10 m roll |
| System Compatibility | Compatible with Gripset Class I, II and III liquid membranes |
Here are some common examples on where Gripset Elastoproof B10 / B50 used by our customers.
