Master Builders Solutions MasterFlow 815
Cementitious precision grout engineered for single lifts of 50 to 500 mm — non-shrink, pumpable, and strong enough to load at 24 MPa within a day.
What is it?
A high-strength, non-shrink cementitious precision grout from Master Builders Solutions, blended with specially graded natural aggregate for deep-pour work.
Where is it used?
Equipment baseplates, sole plates, stanchion pockets, precast connections and form-and-pour repairs where the gap runs 50 mm to 500 mm.
Why use it?
It fills thick clearances in one lift without bleeding, settlement or drying shrinkage, and reaches 24 MPa in a day so plant goes back into service fast.
How is it applied?
Mix each 20 kg bag with roughly 2.5 litres of water to a flowable consistency, then pour or pump under the baseplate from one side until it emerges on the other.
About Master Builders Solutions MasterFlow 815
Most precision grouts run into trouble the moment the annulus gets deep. Pour a standard grout 300 mm thick and you invite bleeding, plastic settlement and heat build-up — exactly the defects that leave voids under a baseplate. MasterFlow 815 was formulated for this situation. Its specially graded natural aggregate bulks out the mix so that deep sections between 50 mm and 500 mm can be cast in a single lift, while the grout hardens free of bleeding, settlement and drying shrinkage. At a flowable consistency it develops 24 MPa in 24 hours and 63 MPa at 28 days, tested to AS 1478.2-2005 on 50 mm cubes.
For Indian plant and infrastructure sites, the practical advantage is working time. The grout holds 74% of its initial 43 cm trough flow after 30 minutes at 23°C and stays placeable even in hot ambient conditions — a genuine consideration for summer grouting in NCR, Gujarat or Rajasthan. It pumps cleanly with a standard grout pump, contains no metallic aggregate that could stain, and meets the non-shrink requirements of ASTM C1090 and CRD-C 621. Space Arc Engineering supplies MasterFlow 815 in 20 kg bags and provides applicator support across Delhi NCR and pan-India.
The technical insight
Two problems dominate deep grout pours: thermal cracking and settlement voids. MasterFlow 815 addresses the first through its aggregate grading — a high proportion of graded natural aggregate dilutes the cement fraction, cutting the heat of hydration that a neat, fine grout would generate in a 500 mm section. It addresses the second through a controlled expansion system: the grout registers positive volume change at 1, 3, 7 and 28 days, which compensates for plastic settlement while the mix is still fluid and keeps the hardened grout locked tight against the underside of the plate. Verified by the simulated bedplate test, this is what delivers the near-full effective bearing area that machine foundations are designed around. The flow-retention chemistry does the rest — half the initial flow is still available a full hour after mixing, so a large pour can be completed from one side without cold joints.
Where it is used
- Grouting heavy equipment baseplates and sole plates with 50-500 mm clearances
- Stanchion bases and structural steel column grouting in single deep lifts
- Precast concrete panel, beam and column connections
- Turbine, compressor and mill foundations needing early return to service
- Form-and-pour concrete repairs in thick sections
- Pocket and void filling in industrial foundations
- Bridge bearing pedestals and crane rail bases where a pumpable grout suits access
- Anchor block and machine plinth infill on plant expansion projects
Key advantages
- Single lifts up to 500 mm deep – no staged pours or intermediate layers in thick clearances
- 24 MPa in 24 hours at 23 degrees C, so machinery can be aligned and loaded quickly
- 63 MPa ultimate strength at 28 days for long-term bearing under heavy plant
- Hardens without bleeding, settlement or drying shrinkage at flowable consistency
- Retains 74% of initial flow after 30 minutes – workable even in hot Indian site conditions
- Pumpable with a standard grout pump for congested or large-area baseplates
- Free of metallic aggregate, so no rust staining on exposed edges
- Meets AS 1478.2-2005 plus the non-shrink requirements of ASTM C1090 and CRD-C 621
Limitations & considerations
- Minimum clearance is 50 mm – for thinner annular gaps a standard precision grout such as MasterFlow 928 is the correct choice
- Not suitable for dry-pack or damp-pack placement; Master Builders Solutions recommends MasterFlow 700 for that consistency
- Quoted strengths are at 23 degrees C – cold weather slows strength gain, so verify site cube results before loading
- Overwatering causes segregation and bleeding; the 2.5 L per bag guide must not be exceeded to chase extra flow
- As a cementitious grout it is not the right pick for high dynamic loading or chemical exposure, where an epoxy grout performs better
- Site strength testing must use 50 mm cube moulds per AS 1478.2-2005 – cylinder moulds give misleading results
Selection & best practice
Prepare the foundation by chipping back to sound concrete, removing laitance and pre-soaking the substrate; remove standing water before the pour. Build tight, leak-proof formwork with a head box on the pouring side and adequate venting opposite. Mix full 20 kg bags with approximately 2.5 litres of water using a paddle mixer or grout pump — a hand-held stirrer may need marginally more water — targeting 40-45 cm lateral flow in the trough test. Never add water beyond what the mix needs to flow; segregation shows up later as a weak, bled surface. Pour continuously from one side only so air escapes ahead of the grout front, and maintain the head until grout rises on the far side. In hot weather, use cool water, shade the bags, and grout early morning. Cure exposed shoulders promptly with wet hessian or curing compound. For deep pours near the 500 mm limit, consult Space Arc’s technical team on placement sequencing before the pour date.
Specifications
| Form / chemistry | Cementitious powder grout with specially graded natural (non-metallic) aggregate |
| Compressive strength (23 deg C, flowable, 50 mm cubes) | 24 MPa at 1 day; 40 MPa at 3 days; 52 MPa at 7 days; 63 MPa at 28 days |
| Pour depth range | 50 mm to 500 mm per lift |
| Flow (trough test, AS 1478.2-2005) | 43 cm initial; design consistency 40-45 cm lateral flow |
| Flow retention (23 deg C) | 74% at 30 minutes; 51% at 60 minutes |
| Water demand | Approx. 2.5 litres per 20 kg bag for flowable consistency |
| Yield | Approx. 10.0 litres per 20 kg bag (about 100 bags per cubic metre) |
| Standards compliance | AS 1478.2-2005; non-shrink requirements of ASTM C1090 and CRD-C 621 |
| Packaging / shelf life | 20 kg moisture-resistant bags; 12 months in cool, dry storage unopened |
Industry use cases
Power & Heavy Industry
Turbine tables, compressor blocks and mill foundations where deep sole-plate clearances must be grouted in one lift and plant loaded within days, not weeks.
Steel & Cement Plants
Stanchion bases, crusher and kiln support plinths with 100-500 mm gaps – the natural aggregate blend keeps heat and shrinkage in check through thick sections.
Infrastructure & Bridges
Bearing pedestals, precast girder connections and pier repairs where a pumpable, code-compliant non-shrink grout is specified by the consultant.
Precast Construction
Panel-to-panel, beam and column joints in precast structures, filled at flowable consistency to achieve full contact without settlement voids.
Plant Expansion & Retrofit
Form-and-pour repairs and new equipment plinths inside running factories, where early strength shortens shutdown windows.
Frequently asked questions
How deep can MasterFlow 815 be poured in a single lift?
When can I load the baseplate after grouting?
How many bags do I need per cubic metre?
Can MasterFlow 815 be pumped?
How is it different from MasterFlow 928?
How much water should be added, and what if I need more flow?
How we position Master Builders Solutions MasterFlow 815
MasterFlow 815 sits in the Master Builders Solutions grout range as the deep-pour specialist. For standard baseplate clearances under 50 mm, we supply MasterFlow 928; for dry-pack or damp-pack packing, MasterFlow 700 is the manufacturer’s recommendation; and where dynamic loading, vibration or chemical attack governs – reciprocating compressors, for instance – an epoxy grout such as MasterFlow 648 is the stronger specification. Buyers comparing brands can also ask us about Fosroc Conbextra GP2 and SikaGrout 214, both stocked by Space Arc, though neither matches the 500 mm single-lift depth that defines MasterFlow 815. Our team can review your clearance drawings and recommend the right grout before you order.
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Authorised distribution, technical advice & professional application across Delhi NCR and Pan-India.