From pour to handover
VDF Flooring Process
A VDF floor is built in sequence. Skipping a step — or rushing curing — shows up later as dusting, weak surface mortar, or joint problems. This is how ASVDF Flooring typically executes vacuum dewatered flooring on industrial and warehouse sites.
1. Site and pour planning
Bay sizes, access, reinforcement, levels, and joint layout are agreed before concrete is ordered. The programme has to leave time for dewatering, trowelling, and curing, not only for the pump.
2. Placement and levelling
Concrete is placed and struck off to level. Screed work sets the flatness the vacuum mats will sit on. A slab that is out of level before dewatering will not be rescued by the vacuum step.
3. Vacuum dewatering
Filter pads and vacuum mats go onto the fresh surface and are connected to the vacuum dewatering unit. Surplus water is extracted so the top layer densifies. This is the vacuum densification step that defines VDF.
4. Power trowel finishing
After dewatering, power trowels close the surface to the specified finish — typically a dense, smooth industrial trowel finish suitable for warehousing or plant use. Floor hardener, if specified, is applied at the finishing stage.
5. Joints, curing, and handover
Saw-cut joints are timed to control cracking. Curing protects the slab while strength develops: IS 456 calls for at least 7 days of moist curing for ordinary Portland cement concrete and at least 10 days where blended cements or mineral admixtures are used, extended in hot, dry weather. Handover follows the curing window agreed with the client so early traffic does not mark a green floor.
What the client prepares before flooring starts
- A compacted, levelled sub-base, with any membrane in place
- Reinforcement, dowels and embedded items fixed as per drawings
- Confirmed concrete supply, pump access and pour timings
- Water and power on site for the vacuum pump and finishing equipment
- A covered or protected area for curing in hot or rainy weather
Quality checks during a VDF pour
- Concrete checked on arrival, with workability matched to placing and dewatering
- Levels and screed rails checked before and during placing
- Dewatering time judged against the slab thickness and the amount of water drawn out
- Floating and trowelling started at the right set, with the surface checked between passes
- Joints cut as soon as the concrete can be cut cleanly, and curing started immediately after finishing
