When the job demands a high-strength bond that won't sag or drip on vertical and overhead applications, even in potable water, ARDEX RA 88 PLUS delivers. This two-component epoxy adhesive and repair compound handles critical concrete repairs, structural bonds, and waterproofing membrane terminations where precision and performance are non-negotiable.
ARDEX RA 88 PLUS was formulated for critical repair and bonding tasks that demand superior non-drip and non-sag performance. It provides high compressive strength and exceptional bond strength across diverse building materials, including concrete, metal, wood, and stone. Its potable water compliance ensures suitability for sensitive applications, owning the job of permanent, high-performance repairs and structural adhesion.
A compressive strength of 87 MPa at 7 days means the repair delivers structural integrity, far exceeding the strength of most concrete it's used on. This ensures permanence in load-bearing applications. Bond strength to hardened concrete reaches 20.1 MPa at 14 days, creating a monolithic repair that resists delamination and failure. With a working time of 45 minutes at 24°C, there is ample window for placement and tooling, while a tack-free cure time of 3 hours at 24°C allows for rapid project progression, mechanical grinding, and overcoating.
Surface preparation is critical. All substrates must be clean, dry, and mechanically roughened. New concrete requires a minimum 28-day cure. Smooth surfaces need mechanical profiling with a wire brush or sandpaper to ensure proper adhesion. For application, cartridge setup involves dispensing a small amount until both components flow evenly and a consistent grey colour is achieved through the mixing nozzle. Maintain substrate and ambient temperatures between 5°C and 35°C; conditioning the product to 21°C–24°C prior to use helps maintain optimal viscosity and reaction time. Clean tools and equipment with a mild solvent immediately after use. Cured material requires mechanical removal.
In crack injection work, ARDEX RA 88 PLUS functions as the critical capping paste. It securely places ARDEX Injection Ports and seals off the crack face before the injection of an ARDEX Crack Injection product. Its non-sag consistency ensures precise placement and prevents resin leakage during the injection phase. For waterproofing, this epoxy is the final sealant for sheet membrane terminations, effectively securing the membrane edge in a reglet and creating a durable, watertight barrier that is crucial for system integrity.
Unlike general-purpose epoxies, ARDEX RA 88 PLUS is specifically formulated for critical overhead and vertical repairs requiring superior non-drip/non-sag performance, high compressive strength, exceptional bond strength, and potable water compliance. For crack injection, ARDEX RA 88 PLUS acts as the capping paste and port adhesive. If the job specifically calls for the actual resin to be injected into structural cracks, the Ardex RA 142 Structural Crack Injection Epoxy is the dedicated product. For general high-strength, quick-setting cementitious repairs, typically for horizontal applications and not requiring potable water compliance, consider Ardex RA 54 Joint Sealant.
Yes, ARDEX RA 88 PLUS is compliant with AS/NZS4020, making it safe for contact with potable drinking water. This allows its use in water tanks, pipe repairs, and other areas requiring drinking water certification.
No, ARDEX RA 88 PLUS is not intended for repairing cracks subject to movement. It is a rigid epoxy designed for static repairs where its high compressive strength is beneficial.
The working time varies with temperature: 90 minutes at 4°C, 45 minutes at 24°C, and 20 minutes at 40°C. Plan your application accordingly, especially in warmer conditions.
No, this product is designed for small patch repairs only. Using it for deeper or larger mass repair areas can generate excessive heat during curing, potentially leading to swelling, smoking, or cracking.
| Application | Key benefit | Primary trades |
|---|---|---|
| Concrete crack and hole repair | Achieves 87 MPa compressive strength at 7 days, providing durable, structural repair for non-moving cracks. | Concreters, general builders |
| Waterproofing membrane terminations | Secures ARDEX sheet membranes and OverFlashing details. Cures in 3 hours at 24°C, allowing faster flood testing. | Waterproofers |
| Overhead and vertical repairs | Excellent non-drip and non-sag performance ensures material stays in place, reducing rework and material waste. | Concreters, repair specialists |
| Anchor bolt installation | Superior bond strength to concrete (20.1 MPa at 14 days) securely fixes anchors without slip. | Plumbers, steel fixers, general builders |
| Underwater pool tile repair | Adheres tiles in wet conditions, allowing targeted repairs without fully draining the pool. | Tilers, pool maintenance |
| Potable drinking water contact | AS/NZS4020 compliance provides assurance for applications in tanks and pipes intended for drinking water. | Plumbers, water infrastructure contractors |
All substrates must be sound, clean, dry, and free of any contaminants. A roughened surface is critical for good adhesion.
Use a grinder to cut the repair area to a minimum depth of 13mm, ensuring clean, square edges. Avoid feather-edging. Roughen the internal surface mechanically.
Mechanically abrade smooth surfaces like metal or stone with a wire brush or sandpaper to create a textured profile for the adhesive to key into.
Correct cartridge setup ensures a perfect 1:1 mix ratio and optimal performance.
Before attaching the nozzle, place the cartridge in the caulking gun and dispense a small amount until both components flow evenly.
Attach the mixing nozzle and dispense material until a consistent, streak-free grey colour is achieved. Discard this initial amount.
Apply the mixed epoxy to the prepared substrate using the appropriate method for the job.
Apply the adhesive to the repair area, slightly overfilling it. Use a trowel to smooth the material flush with the surrounding surface.
Apply a sufficient amount of adhesive to one of the surfaces to ensure complete coverage and fill any gaps when the two parts are brought together.
Allow the material to cure before subjecting it to traffic or mechanical finishing.
Harmful if swallowed. Causes eye and skin irritation and may cause serious eye damage. May cause an allergic skin reaction. May cause respiratory irritation. Suspected of causing cancer. Toxic to aquatic life with long lasting effects. May be corrosive to metals.
Wear protective gloves, clothing, eye protection, and face protection. Ensure adequate ventilation during mixing and application.
Store in original unopened packaging, in a dry place at 23°C and 50% relative humidity for up to 24 months. Check with your local Council regarding the disposal of contents and packaging. Keep out of the reach of children.
Proper surface preparation ensures optimal bond strength and long-term performance. Do not compromise on cleaning or profiling.
Surface prep: New concrete must be at least 28 days old. Mechanically remove all dirt, dust, curing compounds, oils, grease, sealers, and contaminants. Profile the surface by rough-grinding, scarifying, or bush hammering to achieve a roughened texture. Vacuum clean thoroughly.
Primer: Not required, provided the surface is sound, clean, and mechanically profiled.
Surface prep: Ensure surfaces are sound and free from dust, dirt, grease, wax, oil, or any other contaminant. Smooth surfaces must be mechanically roughened with a wire brush or sandpaper to create a profile for adhesion.
Primer: Not required, provided the surface is sound, clean, and mechanically roughened.
| Property | Value |
|---|---|
| Colour Mixed | Grey |
| Working Time | 90 mins @ 4°C, 45 mins @ 24°C, 20 mins @ 40°C |
| Service Temperature After Curing | -7°C up to 50°C |
| Gel Time 60 Gram Mass | 65 mins @ 4°C, 26 mins @ 24°C |
| Tack Free Cure Time | >6 hrs @ 4°C, 3 hrs @ 24°C |
| Compressive Strength | 87 MPa @ 7 days |
| Bond Strength Hardened to Hardened Concrete | 16.9 MPa @ 2 days, 20.1 MPa @ 14 days |
| Bond Strength Plastic to Hardened Concrete | 12.3 MPa @ 2 days |
| Heat Deflection | 51°C |
| Water Absorption | 0.32% |
| Linear Coefficient of Shrinkage | 0.00015% @ 48 hrs |
Here are some common examples on where Ardex RA 88 Plus Multi-Purpose Epoxy Repair Adhesive used by our customers.
