---
title: "Construction of cement floor"
subject: "Building Technology"
chapter: 7
key: "semester_6/building_technology:cement-floor"
source: https://www.bctengineer.com/q/semester_6/building_technology/cement-floor
site: BCT Engineering
---

# Construction of cement floor

Building Technology · Chapter 7: Flooring

- Asked in: 2072 Magh, 4 marks
- Video: [How to Install a Concrete Floor – The Process & Materials Used](https://www.youtube.com/watch?v=lVPqaDstNUg) — HYPE Building
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_6/building_technology/cement-floor
- Whole chapter: https://www.bctengineer.com/md/semester_6/building_technology/chapter-7

## Question

Explain method of construction of cement floor.

## Short answer

Cement concrete floor: hardcore base, 1:2:4 concrete (75-100 mm), 12-25 mm cement-sand (1:2) topping applied while green, trowelled smooth with neat cement, cured 7-10 days.

## Answer

A **cement concrete floor** is made of cement concrete finished with a cement-sand topping. It is cheap, strong, durable and fire-resistant, and is used in houses, godowns, schools and offices.

#### Method of construction
1. **Preparation:** the ground is cleaned, levelled and compacted. A layer of 100-150 mm hardcore (brick soling) is laid and rammed. On damp sites, a damp proof membrane is added.
2. **Base concrete:** cement concrete 1:2:4 (or 1:3:6 for light use), 75-100 mm thick, is laid in panels of about 2 m x 2 m, using wooden or steel strips as screed guides. It is tamped and levelled.
3. **Topping:** while the concrete is still green (within 2-3 hours), a 12-25 mm topping of cement-sand mortar 1:2 is applied.
4. **Finishing:** the surface is levelled with a straight edge and trowelled. Neat cement is then sprinkled on it and finished with a steel trowel (punning) to get a smooth surface. The dividing strips can be removed and the joints filled.
5. **Curing:** the floor is covered with wet sand or gunny bags and kept wet for 7-10 days.

```text
   topping 1:2 (12-25 mm)  ~~~~~~~~~~
   PCC 1:2:4 (75-100 mm)   ..........
   hardcore (150 mm)       oooooooooo
   compacted earth         //////////
```

The floor can be coloured by adding oxide pigments, and a hardener (such as iron filings) is added for heavy-duty floors.

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. What base concrete is used?
   A. 1:10, 5 mm
   B. 1:2:4 (or 1:3:6), 75-100 mm
   C. Pure sand, 50 mm
   D. 1:1:1, 300 mm
   Answer: B. Laid in panels of about 2 m x 2 m. (Key point: Base concrete)

2. When is the topping applied?
   A. After 28 days
   B. After a week
   C. While concrete is still green, within 2-3 hours
   D. Never
   Answer: C. This gives bond. (Key point: Topping timing)

3. What is punning?
   A. Soaking in water
   B. Grinding with stones
   C. Fixing tiles
   D. Sprinkling neat cement and finishing with a steel trowel
   Answer: D. It gives a smooth surface. (Key point: Punning)

4. Curing is done for
   A. 7-10 days with wet sand or gunny
   B. 1 day dry
   C. Not needed
   D. 60 days
   Answer: A. Keeps floor wet. (Key point: Curing)

## Related in Building Technology

- [Floor insulation and sound insulation methods](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Afloor-insulation-sound) — Building Technology, chapter 1
- [Suspended ground floor; tile flooring](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Asuspended-ground-floor-tile) — Building Technology, chapter 7

## Related in other subjects

- [Soil stabilization methods; soil cement construction](https://www.bctengineer.com/question.md?key=semester_7%2Ftransportation_engineering_ii%3Asoil-stabilization-methods-soil-cement-road) — Transportation Engineering II, chapter 3
- [Construction steps of cement concrete pavement](https://www.bctengineer.com/question.md?key=semester_7%2Ftransportation_engineering_ii%3Acc-pavement-construction-steps) — Transportation Engineering II, chapter 3
- [Materials: 115 m² PCC floor, 110 m² plaster](https://www.bctengineer.com/question.md?key=semester_7%2Festimating_and_costing%3Amaterials-pcc-floor-plaster-i) — Estimating and Costing, chapter 4, asked 2×
- [Rate analysis: 25 mm 1:2:4 concrete floor](https://www.bctengineer.com/question.md?key=semester_7%2Festimating_and_costing%3Arate-cc-floor-25mm) — Estimating and Costing, chapter 4