---
title: "Ground floor with mosaic tiling and external wall"
subject: "Building Technology"
chapter: 7
key: "semester_6/building_technology:mosaic-ground-floor-wall"
source: https://www.bctengineer.com/q/semester_6/building_technology/mosaic-ground-floor-wall
site: BCT Engineering
---

# Ground floor with mosaic tiling and external wall

Building Technology · Chapter 7: Flooring

- Asked in: 2070 Bhadra, 8 marks
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_6/building_technology/mosaic-ground-floor-wall
- Whole chapter: https://www.bctengineer.com/md/semester_6/building_technology/chapter-7

## Question

Show a flooring details of a floor (ground) that has a connection with external wall and floor finish with mosaic tiling.

## Short answer

Mosaic finish (12-15 mm) on mortar bed (1:3, 25 mm) over PCC (1:2:4, 100 mm), DPM (polythene), hardcore (150 mm), compacted earth. DPC at plinth level. Skirting 100-150 mm high.

## Answer

The figure below shows a section of a **solid ground floor** with **mosaic finish** meeting an **external brick wall**.

```text
        external wall (230 mm)
     |<---------->|
     |  plaster   |     skirting (mosaic, 100 mm)
     |            |  _/| 
     |            |_/__|__________ mosaic topping 12-15
     |            |....................... mortar 1:3, 25
     |            |ooooooooooooooooooo PCC 1:2:4, 100
     |   DPC      |=====DPM (polythene)===
     |            |xxxxxxxxxxxxxxxxxxx hardcore 150
  GL |            |///////////// compacted earth
     |  plinth    |
     |  foundation|
     +------------+
```

#### Details from the top down
- **Mosaic finish:** marble/china pieces in cement paste, 12-15 mm, with glass or brass dividing strips, ground and polished.
- **Mortar bed:** cement-sand 1:3, 25 mm, to level and bind.
- **Concrete bed:** PCC 1:2:4, 100 mm, laid over the whole room.
- **Damp proof membrane:** polythene sheet, joined to the wall DPC to give a continuous barrier.
- **Hardcore:** 150 mm of brick or stone ballast, rammed.
- **Compacted earth fill** in 150 mm layers.
- **DPC:** 25 mm of cement mortar (1:2) or 40 mm of cement concrete (1:1.5:3) with a waterproofing compound, at plinth level above the finished ground level (plinth usually about 450 mm).
- **Skirting:** mosaic skirting 100-150 mm high on the wall, flush with the plaster, to protect the wall and give a neat edge.

## Check yourself

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

1. How is continuity of damp protection achieved?
   A. The polythene DPM is joined to the wall DPC
   B. A gap is left
   C. Hardcore is omitted
   D. Only a skirting is used
   Answer: A. The DPC sits at plinth level and DPM connects to it. (Key point: DPM and DPC)

2. What is the purpose of mosaic skirting?
   A. Support the PCC
   B. Protect the wall and give a neat edge
   C. Act as DPC
   D. Carry load
   Answer: B. 100-150 mm high, flush with plaster. (Key point: Mosaic skirting)

3. What is the PCC bed?
   A. 1:6, 20 mm
   B. 1:1, 500 mm
   C. 1:2:4, 100 mm
   D. 1:3, 12 mm
   Answer: C. Laid over the whole room above hardcore. (Key point: Layer thickness)

## Related in Building Technology

- [Flooring and its types; special floor finish](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Aflooring-types-special) — Building Technology, chapter 7
- [Suspended ground floor; tile flooring](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Asuspended-ground-floor-tile) — Building Technology, chapter 7
- [Floor finish, wall cladding, floor finishing materials](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Afloor-finish-wall-cladding) — Building Technology, chapter 7
- [Construction of mosaic flooring](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Amosaic-flooring) — Building Technology, chapter 7, asked 2×
- [Terrazzo versus mosaic flooring](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Aterrazzo-vs-mosaic) — 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×

## Related in other subjects

- [Single-storey external wall: stress, brick, mortar](https://www.bctengineer.com/question.md?key=semester_5%2Fconcrete_technology_and_masonry_structure%3Awall-single-storey-100kn-12mm) — Concrete Technology and Masonry Structure, chapter 8
- [Brick and mortar for wall with timber flooring](https://www.bctengineer.com/question.md?key=semester_5%2Fconcrete_technology_and_masonry_structure%3Awall-eccentric-230mm-135kn-timber) — Concrete Technology and Masonry Structure, chapter 8
- [Units: flooring, skirting, railing, half brick wall](https://www.bctengineer.com/question.md?key=semester_7%2Festimating_and_costing%3Aunits-flooring-skirting-railing-wall) — Estimating and Costing, chapter 1
- [RCC floor joist design, 15 m x 6 m hall](https://www.bctengineer.com/question.md?key=semester_6%2Fdesign_of_steel_and_timber_structure%3Afloor-joist-15x6-rcc) — Design of Steel and Timber Structure, chapter 7