---
title: "Solid and suspended ground floor"
subject: "Building Technology"
chapter: 7
key: "semester_6/building_technology:solid-suspended-differ"
source: https://www.bctengineer.com/q/semester_6/building_technology/solid-suspended-differ
site: BCT Engineering
---

# Solid and suspended ground floor

Building Technology · Chapter 7: Flooring

- Asked in: 2073 Magh; 2069 Bhadra, 8 marks (asked 2 times)
- Video: [Part 4 - Suspended Timber Floor - Construction Studies](https://www.youtube.com/watch?v=ds_Gvu5Pfyc) — Mr. Josh Copeland
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_6/building_technology/solid-suspended-differ
- Whole chapter: https://www.bctengineer.com/md/semester_6/building_technology/chapter-7

## Question

With the help of neat sketches, explain (differentiate between) solid and suspended ground floor.

## Short answer

Solid ground floor rests directly on compacted earth with hardcore, sand blinding, DPM, concrete, screed, and finish. Suspended ground floor has a ventilated void below, supported by sleeper walls or beams with joists and boarding. Solid floors are cheaper but colder; suspended floors suit damp sites and provide warmer timber surfaces.

## Answer

A **solid ground floor** rests directly on the filled ground, while a **suspended ground floor** is raised above the ground with a ventilated air space below.

| Point | Solid ground floor | Suspended ground floor |
|---|---|---|
| Support | Rests directly on compacted earth/hardcore | On joists/slab supported by sleeper walls or beams |
| Air space | None | Ventilated void below |
| Construction | Hardcore, sand blinding, PCC 100-150 mm, DPM, screed and finish | Sleeper walls, DPC, wall plate, joists, boarding, air bricks |
| Dampness | Needs a good damp-proof membrane | Dry, as ventilation removes moisture |
| Suitable site | Dry, firm ground | Damp sites, high water table |
| Cost | Cheaper and faster | More costly |
| Finish | Tile, cement, terrazzo, stone | Timber boards, wood parquet, RCC slab |
| Warmth | Colder surface | Warmer (timber) |

```text
  SOLID                    SUSPENDED
  finish  =========        boards  ==========
  screed  ~~~~~~~~~        joists  |_|_|_|_|_|
  PCC     .........        void      (air)
  DPM     ---------        sleeper [|]  [|]
  hardcore ooooooo         concrete .........
  earth   ///////////      earth   //////////
```

## Check yourself

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

1. How does a solid floor differ in support?
   A. It rests on joists over a void
   B. It is hung from beams
   C. It is on sleeper walls
   D. It rests directly on compacted earth/hardcore
   Answer: D. A suspended floor is on joists or slab over sleeper walls. (Key point: Support)

2. Which floor needs a damp-proof membrane?
   A. Solid ground floor
   B. Suspended floor only
   C. Neither
   D. Both equally with no ventilation
   Answer: A. A solid floor relies on a DPM; the suspended floor is kept dry by ventilation. (Key point: Dampness)

3. Which site suits a suspended floor?
   A. Dry firm ground
   B. Damp site with a high water table
   C. Rock outcrop
   D. Any site, being cheaper
   Answer: B. Suspended floors suit damp sites. (Key point: Suitable site)

4. Compared with a solid floor, the suspended floor is
   A. Cheaper and colder
   B. Cheaper and faster
   C. More costly but warmer with timber
   D. Same cost
   Answer: C. Solid floors are cheaper and faster; suspended timber floors are warmer. (Key point: Cost and warmth)

## Related in Building Technology

- [Suspended ground floor](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Asuspended-ground-floor) — Building Technology, chapter 7, asked 2×
- [Suspended ground floor; tile flooring](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Asuspended-ground-floor-tile) — Building Technology, chapter 7
- [Solid ground floor](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Asolid-ground-floor) — Building Technology, chapter 7, asked 2×
- [Ground floor with mosaic tiling and external wall](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Amosaic-ground-floor-wall) — Building Technology, chapter 7

## Related in other subjects

- [Differentiate GVF, RVF and SVF with sketches](https://www.bctengineer.com/question.md?key=semester_4%2Fhydraulics%3Adifferentiate-gvf-rvf-svf-sketch) — Hydraulics, chapter 5, asked 5×