View source for Construction-of-Low-Cost-Houses/C2/Building-Wall-Foundation-using-Bricks/English

Title of the Script: '''Building wall foundation using bricks'''

Authors: Dr. Narsingh Varma, Chitra Devi and Madhuri Ganapathi

Keywords: bricks, conventional bricks, modular bricks, water, cement, sand, mortar, video tutorial.


{| border=1
|-
|| Visual Cue
|| Narration
|- 
|| '''Slide Number 1'''

'''Title Slide'''
|| Welcome to this Spoken Tutorial on '''Building wall foundation using bricks'''.

|- 
|| '''Slide Number 2'''

'''Learning Objectives'''
|| In this tutorial we will learn about,


* Materials used to build a wall foundation.
* Classification of bricks.
* Field Test on bricks.
* Steps to build a wall foundation using burnt clay bricks.

|- 
|| '''Slide Number 3'''

'''Pre-requisites'''

https://'''spoken-tutorial.org'''
|| To practise this tutorial, learners should be familiar with basic construction methods.


For the prerequisite tutorials, please visit this site.
|- 
||  1a.brick mortar and cement 

1.Good quality bricks

2.Cement

3.Sand

4.Water 5.mortar

6a. Mortar mixed on concrete floor

|| Materials required to build a wall foundation are 


Burnt clay bricks and cement mortar


Cement, sand and water are mixed together to make cement mortar.

|- 
|| '''Slide number 4'''

'''Types and characteristics of Bricks'''
|| Selecting bricks is an important criteria for brick wall foundation.

Let us now see about the types and characteristics of bricks .


According to '''IS code 1077''' bricks are classified based on size and strength.

|- 
|| 7.Conventional bricks

7a.Conventional bricks2

8.Modular brick

8a.Modular brick 2
|| Classification of burnt clay bricks based on the size 

Conventional bricks: size

230 mm x 110 mm x 70 mm

230 mm x 110 mm x 30 mm

Modular bricks: size

190 mm x 90 mm x 90 mm

190 mm x 90 mm x 40 mm.

|- 
|| 9.classification of bricks image
|| Based on compressive strength bricks are classified into different classes.

Brick Class designation is shown in this table.

|- 
||  10.well burnt bricks

11.brick struck

11.brick struck.mp4


12. Brick texture


1.good quality bricks

15. load bearing walls

15a. load bearing walls


||  Characteristics of good quality well Burnt Clay Bricks


Well burnt bricks should be without any cracks.

They should give a clear metallic sound when two bricks are struck together.

They should have uniform colour, and good texture.


Bricks should be of standard size.


Brick should have a perfectly rectangular shape with sharp edges.

These bricks are good for foundation, load bearing walls and external walls. 

|-
|| Under Burnt Clay Bricks 


16.under burnt bricks

||  Under burnt clay bricks are dull in colour compared to well burnt bricks.

They have low strength and high water absorption capacity.

|-
|| Over Burnt Clay Bricks


17.overburnt bricks

||Over burnt clay bricks


They are irregular in shape as they get distorted due to over burning. 


They have non-uniform colour and texture. 


These are not good for coursed masonry construction.

|-
|| '''Slide Number 5'''

'''Simple Field Tests on Bricks'''
|| Simple field tests on bricks.

Water absorption test

It determines the percentage of water absorbed by a brick when soaked in water.


Let’s see the procedure of the test according to IS code: 3495-Part 2
|- 
||  18. Weighing brick


18a. Soaking of bricks

18b. Soaking of bricks

18c. Bricks in water

18d. Wipe with cloth

18. Weighing brick


Write in base slide as “The formula to calculate water absorption is:

100 (W2-W1)/W1”

|| Weigh a completely dry brick, let its weight be W1.

Immerse the brick in water for 24 hours.

Take the brick out of water.


Wipe it with a wet cloth to remove traces of surface water.

Weigh the brick within 3 minutes of removal from water.


Let its weight be W2.

The formula to calculate water absorption is:

100(W2-W1)/W1.

|- 
|| '''Slide number 6 + 7'''

'''Permissible Water Absorption of Bricks'''

||  Maximum water absorption for bricks of class 12.5 and below is 20 percentage.


Maximum water absorption for bricks above class 12.5 is 15 percentage.


Lesser the water absorption, better is the quality of brick.


Hence bricks above class 12.5 have better quality.


These provisions are according to '''IS code: 1077'''.
|- 
|| 13. Brickfall a

13. Brick fall b

13. Brick wall a- potrait

13. Brick wall b- potrait

|| Strength Test


Drop a brick flat on a hard surface from 1 metre height.

A good brick will not break.


|- 
|| Scratch surface of brick with nail.


14. Scratch brick


14a. Scratch brick mp4

|| Hardness Test


Scratch surface of brick with nail.

Scratch impressions will not be formed on the surface of a good brick. 

|- 
|| '''Slide number 8'''

'''Foundation design '''
|| Let’s discuss foundation design and preparatory work for construction of a wall.

Design wall foundation details given below are according to '''IS code 1080'''

|- 
|| 19a. Width of wall foundation

19b. Width of wall foundation

19c. Width of wall foundation

19d. Width of wall foundation

20. Brick work in steps

|| Base course of brick work for footing B = W + 300 in millimeter.

Where W is the width of the wall above the plinth. 

Foundation masonry is done in steps. 

Minimum thickness at the end is 150 mm.

Minimum width of offset is 75 mm.

Maximum ratio of step thickness and offset should be 2.

Brick work for foundation should start after curing the base concrete.


Base concrete curing should be a minimum of 3 days.

|- 
|| 7. Conventional brick


8. Modular brick
|| Minimum foundation width, using conventional bricks:

* B = 230+300 = 530 mm thick

Where 230 mm is the length of conventional bricks.

Minimum foundation width, using modular bricks: 

* B =190 + 300 = 490 mm thick

Where 190 mm is the length of modular brick.

|- 
|| '''Slide Number 9'''

'''Mix proportioning of Cement Mortar'''

||Mix proportioning of cement mortar

Cement mortar mixture 1:3 is used for laying the brick wall foundation.

|-

||
21. Cement bag

21a. 3 box of sand

21b. Water

21c. Cement water in GI tray

32. Good mortar mix
||  1 bag of cement, 3 boxes of sand and 15 litres of water.

The materials are mixed together in a GI tray.

Add more water if needed to make the mortar homogeneous and workable.

A good homogeneous mix will have all sand grains coated with cement.

|-
|| '''Slide Number 10'''

'''Construction Procedure'''

||Construction procedure for laying of bricks.


All provisions mentioned are according to '''IS code 2212'''

|-

|| 23. Workplace bricks

24. Lines and pins

24a. Lines and pi


28. Brick wall with plinth

29. Brick wall with proper joint

|| Remove the soaked bricks from the soaking tank and store near the workplace.


Fix foundation wall alignment using lines and pins.

Foundation masonry should start simultaneously from both the ends of the wall.


Lay the cement mortar 12 mm thick for a small length and proceed with laying bricks.


Do not spread mortar on a full wall at a time.


Provide 10 mm thick vertical joints.

Joints should be symmetrically staggered in subsequent layers.

|- 
|| Write on the image as curing


30. Curing

30a.Curing of bricks
|| Curing 


Curing must be done by sprinkling water or by covering it with hessian cloth.


Curing of brick work must be done for a minimum of 14 days.
|- 
||31. Surface dry bricks


32. Good mortar mix

32a. Headpan with mortar mix

28. Brick wall with plinth


29. Brick wall with proper joint

30. Curing

30a. Curing of bricks
|| Quality control


Bricks being used must be surface dry but fully saturated with water.


Mortar must be fresh, workable and homogeneous.


Vertical joints of immediate lower or higher course should not be in the same line.


All joints must be fully filled with mortar.

Mixed cement sand mortar must be consumed before any work break.


Regular wetting of masonry must be ensured.


|- 
|| 
|| With this we come to the end of this tutorial. Let us summarise.
|- 
|| '''Slide Number 11'''

'''Summary'''
|| In this tutorial we have learnt about,

Materials used to build a wall foundation.

Classification of bricks.

Field Test on bricks.

Steps to build a wall foundation using burnt clay bricks.

|- 
|| '''Slide Number 12'''

'''About Spoken Tutorial project '''

|| The video at the following link summarizes the Spoken Tutorial project.

Please download and watch it. 

|- 
|| '''Slide Number 13'''

'''Spoken Tutorial workshops'''
|| The Spoken Tutorial Project team:

conducts workshops and gives certificates.

For more details, please write to us.
|- 
|| '''Slide Number 14'''

'''Forum for specific questions'''

|| Please post your timed queries in this 

forum.
|- 
|| '''Slide Number 15'''

'''Acknowledgement'''
|| The Spoken Tutorial Project was established by the Ministry of Education, Government of India.


|- 
|| '''Slide Number 16'''

'''Thank you'''
|| This tutorial is contributed by Dr. Narsingh Varma,Chitra Devi and Madhuri Ganapathi from IIT Bombay


Thank you for joining.
|-
|}