



Fosroc Conbextra GP2 Cementitious Grout, 25kg
- Manufacturer: Fosroc
- Product: Conbextra GP2, Non-Shrink Cementitious Precision Grout, Chloride-free
- Compressive Strength: 55 N/mm² at 7 days (minimum) · 65 N/mm² at 28 days
- Water Ratio: 4.0 to 4.5 litres per 25 kg bag
- Working Time: Pour within 15 to 20 minutes of mixing
- Packaging: 25 kg bag
- Application Areas: Machine base plates, structural anchoring, precast elements and void repair
Fosroc Conbextra GP2 is a high-strength, non-shrink, chloride-free cementitious precision grout for gaps from 10 mm to 100 mm. Its gaseous expansion system prevents settlement, and it gives high early and ultimate compressive strength — at least 55 N/mm² at 7 days and up to 65 N/mm² at 28 days in flowable consistency — for heavy-duty jobs such as machine base plates and structural anchoring. Mix 25 kg of powder with 4.0 to 4.5 litres of water and pour within 15 to 20 minutes. Never retemper it.
Key Features
- Non-Shrink: Gaseous expansion removes shrinkage and settlement, for full load transfer
- High Early and Final Strength: Suited to heavy machinery and structural loads
- Free-Flowing and Chloride-Free: Fills intricate voids without air pockets, and won't corrode steel or reinforced concrete
Technical Specifications
| Specification | Details |
|---|---|
| Manufacturer | Fosroc |
| Product | Conbextra GP2 |
| Type | High-strength, non-shrink, cementitious precision grout |
| Gap Range | 10 mm to 100 mm |
| Consistency | Flowable or fluid |
| Expansion System | Gaseous expansion, activated by water |
| Compressive Strength — 7 Days | 55 N/mm² minimum (flowable consistency) |
| Compressive Strength — 28 Days | 65 N/mm² (flowable consistency) |
| Fresh Density | ~2220 kg/m³ |
| Water per 25 kg Bag | 4.0 to 4.5 litres of clean water |
| Mixing | Mechanical mixer or slow-speed drill with grout paddle, 3 to 5 minutes |
| Working Time | Pour within 15 to 20 minutes of mixing; initial set about 20–30 minutes at ~30°C |
| Curing | Keep exposed surfaces damp for at least 7 days |
| Composition | Chloride-free |
| Packaging | 25 kg bag |
Primary Applications
- Machine Base Plates: Grouting base plates for heavy industrial machinery, turbines and compressors
- Structural Anchoring: Columns, structural steel frames and anchor bolts
- Precast Concrete: Grouting precast concrete elements
- Void Repair: Repairing honeycombed concrete or filling structural voids
Usage Guidelines
- Add the Water: Mix 25 kg of powder with 4.0 to 4.5 litres of clean water for consistent flow
- Mix Mechanically: Use a mechanical mixer, or a slow-speed drill with a high-shear grout paddle, for 3 to 5 minutes to avoid lumps. Don't hand-mix
- Place: Pour continuously within 15 to 20 minutes of mixing, preferably from one side
- Never Retemper: If the grout starts to stiffen after about 20 minutes, don't add water and don't vibrate it. Throw it away, because that breaks its structure, cancels the expansion and ruins its strength
- Cure: Keep exposed surfaces damp for at least 7 days
Why Buy from HomeRun?
- Authentic Fosroc Product: Verified genuine product sourced from authorized Fosroc channels
- 60-Minute Bangalore Delivery: Express delivery to active service zones – ideal for active construction and installation projects
- Project-Friendly Availability: Single-bag ordering of the 25 kg bag for base-plate-by-base-plate procurement on residential, commercial and industrial projects
1) Does the grout shrink or pull away from base plates over time?
No. Conbextra GP2 is a non-shrink precision grout with expansive agents that counteract plastic and drying shrinkage, so there is continuous contact between the foundation and the steel base plate and reliable long-term load transfer.
2) Can I hand-mix it with a shovel or trowel for small anchoring patches?
Hand-mixing is strongly discouraged, as it leaves dry powder pockets, uneven water and trapped air. Use a heavy-duty slow-speed drill with a high-shear grout paddle for 3 to 5 minutes to get full flowability and the rated strength.
3) How long do I have to pour it, and can I fix a stiffening mix?
Initial set begins about 20 to 30 minutes after mixing at around 30°C, so mix, transport and pour within 15 to 20 minutes. Never add extra water to a stiffening mix and don't vibrate it once setting begins — that breaks the chemical structure, cancels the expansion bubbles and reduces final strength. Discard it instead.
4) How does the expansion system work?
A built-in gaseous expansion system activates on contact with water, producing micro-fine gas bubbles that expand the grout slightly before it hardens. This pushes it into every void and bolt thread for a tight mechanical lock with no settlement risk.
5) What gap sizes and jobs is it suitable for?
Gaps from 10 mm to 100 mm, for heavy-duty work such as machine base plates, turbines, compressors, steel column anchoring, and repairing honeycombed concrete or voids.
- Return within 24 hours of delivery for:
- Damaged or defective product
- Wrong or missing item
- Product cannot be returned once opened or used
- Refer to Refund Policy for complete details
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