The roof slab of a G+1 house is a large, continuous pour. How the concrete is made — in a plant or on your plot — affects its quality, the speed of the pour and the risk of cold joints.
How They Compare
| Ready-mix (RMC) | Site-mixed | |
|---|---|---|
| Batching | By weight, in a plant, to a mix design | Usually by volume (boxes) on site |
| Water control | Measured | Depends on supervision |
| Consistency | High | Variable |
| Speed | Fast, continuous supply | Limited by mixer and labour |
| Minimum quantity | Usually a transit load (≈6 m³) | Any |
| Access needs | Road, turning space, firm ground | Minimal |
| Storage on site | None | Cement, sand, aggregate stockpiles |
| Standard | IS 4926 | IS 456 practice |
Cost Compared
Comparing per cubic metre fairly means adding up everything site mixing needs: cement, sand, aggregate, mixer hire, fuel, labour and wastage. RMC's price includes all of that, plus delivery; pumping is extra. For small pours, site mixing is usually cheaper; for a full slab, the difference narrows and RMC's consistency and speed often justify it.
When RMC Makes Sense
- Slab pours of several cubic metres that should go in without a break.
- Higher grades (M25 and above) where a design mix matters.
- Tight sites with no room for stockpiles — if the truck can reach.
- Hot weather, when fast placing reduces cold-joint risk.
When Site Mixing Makes Sense
- Footings, column lifts, lintels and small pours.
- Narrow lanes a transit mixer cannot enter.
- Supervised batching with measuring boxes, controlled water and a needle vibrator.
Pour-Day Checklist for RMC
- Confirm grade, slump, quantity and delivery schedule in writing.
- Check road access, turning space and pump position in advance.
- Check the delivery ticket: grade, quantity, batching time.
- Do a slump test on arrival; refuse water added at site.
- Take cubes.
- Keep labour and vibrators ready so trucks do not wait.
The Short Version
RMC for big slab pours on accessible sites, site mixing for small pours and tight lanes. Either way, control water, compact properly and take cubes.
