11
Mapei Kerapoxy Adhesive: A Technical Overview
Mapei Kerapoxy Adhesive is a two-component, epoxy resin-based, thixotropic adhesive classified R2T. It trowels cleanly, holds on verticals with no slip, and applies up to 10 mm in one coat. On-site productivity is supported by a workable pot life of ~45 minutes at 23 °C, open time ~60 minutes and adjustment time ~130 minutes. Floors are trafficable in 10–12 hours and ready for service in ~2 days, enabling reliable program sequencing for tilers and builders. The adhesive cures by chemical reaction (no shrinkage) to deliver high shear strength with excellent durability and resistance to ageing, moisture, oils and common chemicals across Australian climate zones (service range approx. −20 °C to +100 °C).
Core Features & Specifications
- R2T classification: reactive, improved adhesive with no vertical slip for confident wall installs.
- Thixotropic body: trowels easily and stays where placed, reducing sag and rework.
- Single-coat up to 10 mm: fills irregularities and backs of special pieces in one pass.
- Work times that suit site realities: pot life ~45 min, open time ~60 min, adjustment ~130 min (23 °C, 50% RH).
- Fast return to service: light foot traffic 10–12 h; ready for use ~2 days.
- High final strength: shear bond (EN 12003): initial ~7 N/mm²; after water/thermal shock ~4 N/mm².
- Broad substrate compatibility: cement-based screeds/renders, gypsum/anhydrite (with primer), ferrous metals (prepared), FRP/fibreglass pools.
- Consumption guide: ~1.5 kg/m² per mm of thickness.
- Mix ratio by weight: 80 : 20 (A : B); use complete pre-dosed packs for accuracy.
- Application temperature: +10 °C to +30 °C.
The Mapei Kerapoxy Adhesive Advantage
- Eliminates slip on walls, so set-out stays true and clean-up is minimal.
- Chemical-cure system with no shrinkage—keeps tiles locked in under thermal and moisture cycling.
- Reliable schedule control with predictable walk-on and handover times.
- Confidence on difficult substrates (with correct prep/priming), reducing call-backs.
Proactive Troubleshooting
Scenario: Bonding over damp or green screeds
Potential Outcome: Compromised adhesion and delayed cure, risking delamination.
Adheseal Best Practice: Ensure screeds/renders are fully cured and dry; follow one-week-per-cm guidance for cement screeds unless special rapid binders are used. Confirm moisture before proceeding.
Scenario: Using partial or off-ratio mixes
Potential Outcome: Under-cured adhesive with reduced strength and chemical resistance.
Adheseal Best Practice: Always blend complete pre-dosed packs (A : B = 80 : 20 by weight) with a low-speed mixer until uniform; avoid estimating by eye.
Applications in Practice: Trade Scenarios
For Tilers (On-site Applicator): Vertical porcelain on bathroom walls
The Professional's Challenge
Large-format porcelain tends to slip on walls, and bathrooms often run on compressed schedules that demand dependable next-day access.
The Adheseal Solution
Use a suitable notched trowel; back-butter ribs if required. The thixotropic body holds tiles in line with no vertical slip, while the 10–12 h walk-on window keeps trades moving.
Best Practice Note
Observe the ~60 min open time; spread only what you can tile within that window. Check plumb/level during the 130 min adjustment period for perfect alignment.
For Pool Contractors (Specifier/Applicator): Fibreglass pool tiling
The Professional's Challenge
Pools demand rigid, chemically resistant bonds on FRP shells with constant water exposure.
The Adheseal Solution
Kerapoxy Adhesive is specified for bonding in fibreglass pools. Abrade/clean the FRP, then apply the epoxy bed; press tiles firmly to ensure full contact and butter special pieces.
Best Practice Note
Maintain strict surface prep and keep the shell dry during application and cure to preserve chemical resistance and final bond strength.
For Builders (Business Owner/Operator): Marble sills & thresholds
The Professional's Challenge
Dense stone needs a non-shrinking, high-strength bed that won’t creep or stain, with predictable program timing.
The Adheseal Solution
The epoxy system cures without shrinkage and achieves high shear strength. Use up to 10 mm single-coat to true up irregularities; expect light traffic in 10–12 h and service in ~2 days.
Best Practice Note
Pre-dry fit and plan handling to work within the ~45 min pot life. Mix complete packs to maintain the 80:20 ratio for consistent results across runs.
Frequently Asked Questions
Can I thin Kerapoxy Adhesive with water or solvent to extend pot life?
No. Do not add water or solvents—this compromises cure and final strength. Use full, pre-dosed packs and mix at low speed, then place within the ~45 minute pot life at 23 °C.
Is it suitable for sealing flexible or movement joints?
No. Kerapoxy Adhesive is a rigid bedding adhesive. For movement joints, use an appropriate elastic sealant (e.g., Mapesil AC or Mapeflex PU21 where specified).
What primers are recommended on gypsum or plasterboard?
Consolidate gypsum/anhydrite with a primer such as Primer EP or Eco Prim T as directed. Ensure the surface is dry, sound and dust-free before application.
Applications & Benefits
| Application / Use Case | Key Benefit | Primary Trades |
|---|---|---|
| Ceramic/porcelain wall tiling | No vertical slip; predictable open/adjustment windows | Tilers, Builders |
| Stone thresholds, sills, special pieces | Rigid, non-shrinking bed with high shear strength | Builders, Tilers |
| Fibreglass (FRP) pools | Epoxy bond suited to immersed service with chemical resistance | Pool Contractors, Tilers |
| Bullnose/special shapes | Back-buttering and up to 10 mm build in a single coat | Tilers |
Applying Mapei Kerapoxy Adhesive: Enhanced Protocols & Best Practices
-
Surface Preparation
Substrates must be cured, dry, clean and sound. Remove dust, laitance, oils, paints and waxes. Keep surfaces dry—do not apply to wet substrates.
Cement-based
Cure per thickness; mechanically prepare if required to achieve a clean, open surface.
Gypsum/Anhydrite
Consolidate with Primer EP or Eco Prim T; allow to dry.
Timing: Only proceed when moisture is within acceptable limits and the area is at +10 °C to +30 °C.Pro Tip: Dry-fit large pieces and plan lifts to minimise time off the trowel. -
Mixing
Use complete pre-dosed packs (A:B = 80:20 by weight). Add B into A; mix with a low-speed drill until a smooth, uniform paste forms.
Low-Speed Mechanical Mix
Keep speed low to avoid heat build-up and pot life loss.
Small Batches
If splitting, weigh accurately to maintain 80:20 ratio. Do not estimate by eye.
Timing: Pot life ~45 min at 23 °C; warmer conditions shorten this.Pro Tip: Stage materials and set-out before mixing to maximise working time. -
Trowelling & Placement
Spread with a suitable notched trowel. For special shapes/bullnose, butter the back to fill voids. Press tiles to ensure full contact.
Open/Adjustment Times
Open time ~60 min; adjustment ~130 min at 23 °C. Monitor in warmer conditions.
Thickness
Apply up to 10 mm in a single coat as required to true the bed.
Timing: Light traffic 10–12 h; ready for use ~2 days (23 °C).Pro Tip: Check bond by lifting a tile to verify full buttering and coverage on critical areas. -
Cleaning
While fresh, clean tools/tiles with water. Once hardened, remove mechanically or with a suitable remover.
Pro Tip: Keep a bucket and sponges ready—early wipe-down avoids time-consuming mechanical removal.
Limitations & Safety
Product Limitations
Not for flexible/movement joints. Use a suitable elastic sealant where movement is expected.
Do not add water/solvents to alter workability or pot life.
Do not apply on wet, dirty, crumbly or uncured substrates; ensure surfaces are dry and sound.
Apply only between +10 °C and +30 °C. Warmer conditions reduce working time.
Safety & Handling Requirements
Personal Protective Equipment
Wear chemical-resistant gloves and eye protection. Components may irritate skin/eyes and cause sensitisation in sensitive users.
Ventilation Requirements
Use in well-ventilated areas. Avoid vapour build-up in confined spaces.
Fire & Handling Precautions
Avoid ignition sources. Prevent contamination with other epoxies/hardeners. Store sealed packs as supplied.
Emergency First Aid
Eyes:
Rinse cautiously with water for several minutes; seek medical attention.
Skin:
Wash with plenty of soap and water; remove contaminated clothing.
Inhaled:
Move to fresh air and keep at rest; obtain medical advice if symptoms persist.
Swallowed:
Rinse mouth; do not induce vomiting; seek urgent medical attention.
Seek medical attention immediately in all cases of serious exposure.
Mapei Kerapoxy Adhesive Application Guide
Cement Screeds/Renders
Surface Preparation
Fully cured, dry, sound and clean. Remove laitance, dust, oils and coatings. Observe typical one-week-per-cm curing guidance unless rapid systems are used.
Primer Requirements
No primer typically required
Ensure dry substrate; do not apply to wet surfaces.
Gypsum/Plasterboard/Anhydrite
Surface Preparation
Dry, dust-free, sound. Remove weak or friable areas.
Primer Requirements
Primer required for critical applications
Consolidate with a suitable primer and allow to dry per instructions.
Primer EP or Eco Prim TFerrous Metal
Surface Preparation
Abrasive blast to remove rust/scale; degrease and clean. Dry surface only.
Primer Requirements
Primer optional depending on exposure
Ensure a clean, reactive surface profile before bonding.
FRP/Fibreglass (Pools)
Surface Preparation
Abrade to a uniform matte, clean thoroughly and keep dry during application and cure.
Primer Requirements
No primer typically required
Ensure full contact; butter special pieces.
- Choosing a selection results in a full page refresh.