How much material for Brick work ?

Hello Friends ,

Do you know how to calculate the material required for constructing 1 CuM of brick masonry ? This information is useful for :

1. Calculating the material to be brought for the brick masonry.
2. Doing rate analysis
3. Making a detailed estimate

Today we shall solve one example so that you are able to understand each step with utmost clairity.

Here we go.

Hope you are able to properly get the steps .

In case of any queries , please do write to me through this blog.

Blog Stats for future reference :

Brick work at London :02

The exposed brick work is done with facing bricks.

these bricks are smaller in size.

have got a better surface finish ,uniform colour and texture and are quite compact.

Normal trend is to keep the external exposed surface without plaster but carry out cement plastering on all internal faces of the walls.

Here we are seeing at the Hampton court palace at London .

Why do we water bricks or concrete blocks before taking them for use in construction?

Normal question which comes to our mind is why do we wet the bricks before use ? Right ? So this article answers this basic query which everyone has .

There are three reasons for submerging bricks/blocks:

1. Test for absorption: A brick is submerged in water for 24 hours. If its weight after 24 hours exceeds its dry weight by 20%, the brick is not used for construction.

2. Test for presence of soluble salts: After 24-hour submergence, if grey/white deposits occur on the brick, soluble salts are present. If white deposits cover more than 50% of the surface, the bricks are not used for construction purpose.

3. Quench the thirst: Its said that bricks are very thirsty. So the selected bricks are submerged for sufficient time so that they absorb sufficient water and fill most of their pores with it. Or else they will absorb the water of the mortar, thus reducing its strength to a great strength.

Edit: Bricks are soaked also to remove dirt from their surface. Thanks for the point Sanchit Bajaj.

Why do we water bricks or concrete blocks before taking them for use in construction?

Break the walls ….

Overview:

The concept of walls is so much integrated into the psyche of human beings that we often use the word wall in literature such  as ” removing walls between different cultures “

Walls have got a definite place in the scheme of the buildings. Cannot imagine a building without walls.
Walls define spaces and offer privacy , security .Walls can be made in various materials .Walls can be designed as  load bearing walls  or panel / partition walls depending upon the design philosophy of the building.
This article takes the readers into the wonderland of walls.

Masonry walls :

Stone walls:
Raw material:
Hard stones such as black trap Basalt
Density : Density : 2400 Kg / CuM.

Joined with either lime mortar or cement mortar.

Can be further classified as :

Ashlar masonry :
Individual stone is hand dressed manually and given geometry and shape. Process is time consuming and requires specific skills. Mass production is not possible and hence speed hampers.

Coursed rubble :
Process similar to ashlar but it is not that precise.

Un-coursed rubble :
Stones are not dressed but are used with certain skills so that aesthetics is maintained.

Random rubble masonry :
Can be used for load bearing as well as  non load bearing walls .
Larger thickness restricts wall heights.
Used in forts.

Red clay Brick work :
Raw material:
Clay , coal powder.
Density : Density : 1600 Kg / CuM.
Joined with either lime mortar or cement mortar.
Can be used for load bearing as well as  non load bearing walls.

Fly ash brick :
Raw material:
Fly ash , cement and grit
Density : 1900 Kg/CuM.
Joined with cement mortar.
Can be used for non load bearing walls.

Hollow concrete blocks :
Raw material:
Cement , sand & grit
Density : 1200 Kg/CuM.
Joined with  cement mortar.
Can be used for non load bearing walls.

A.A.C blocks ( c4x blocks ) :
Raw material:
Cement , quartz sand ,calcined gypsum and aluminum powder.
Density : 600 Kg/CuM.
Joined with  cement mortar or with resin based chemicals.
When chemical is used for joining , curing is not needed.
Can be used for non load bearing walls.

Other walls ( called as partitions ) :

RCC walls :

Solid wood partition in Carved wood :
Wooden partition with veneers:
Aluminum framework with glass :
Sandwiched Glass :
PVC panels :
Gypsum panels on wooden frames:
Wire mesh fencing on angle iron frames:
Mud on bamboo Matt

Why so many bricks ???

In my experience , the subject of estimation is quite boring to the students as well as field people.

In that context , we are going through a series of articles devoted to the arithmetic involved in construction.

We have already discussed the estimation of materials in concrete

( Read post : Vow..what a concrete )

Now we shall travel in the masonry today.

If you get bored , just Stop and take a break.

Take a scrap pad and a calculator and do some jugglery yourselves.

That’s how you shall keep aligned .

Re-continue and reflect as many times as you feel.

There is no hurry.

Happy Calculating !

Overview:

We talked about the general aspects of the masonry in the previous post.
We also spoke about  the stone masonry

( Read : Throw the stone..carefully )

Now we shall learn the arithmetic issues involved in counting the bricks.

We shall  be able to find out the :
Number of bricks needed for the masonry work and also the mortar needed for the job.
In other words ,for a given masonry wall we shall be able to compute:

1.No of bricks

2.No of cement bags
3.Sand

And then we can also find out the total material cost.

This shall help us in:
1.Budgeting for materials
2.Ordering the material

Ok ? so all geared up ?
let us begin..here we go:

The Data:
The brick wall which we need to build is 5 m long, 4 m high and it is 200 mm thick.
It is to be jointed in Cement mortar 1:6.
The bricks of size 200 mm x100 mm x 70 mm have been approved.

The method:
1.Calculate the volume of one brick :
0.2m x 0.10m x 0.07m = 0.0014 CuM.
2.Find number of bricks per CuM:
= 1/0.0014 = 714 nos.

So 714 bricks shall be needed if there is no mortar joint. Right ?

3. Now,assume that there is a mortar joint of 10 mm thickness between the  bricks.

So, increase each dimension of brick by 10 mm.

Thus,the volume of each brick with mortar shall be :
0.21 x 0.110 x 0.08 =0.001848 CuM.

4..Again, Find number of bricks per CuM:

= 1/0.0011848  = 541 nos.

5.Thus, number of bricks have reduced from 714 to 541 due to the presence of mortar.

6.Therefore, 714 – 541 = 173 Bricks represent the volume of cement mortar.

173 x 0.0014= 0.2422 CuM.
7.Summary I:

We shall need 541 bricks and 0.24 CuM of cement mortar for 1 CuM of brick work.

8.Now we also need to find out how many cement bags and how much quantity of sand is needed

for 0.24 CuM of mortar .

Let us assume that the mortar quantity is CuM.

The mix is CM 1:6.
We shall use dry mix method.

Cement: [1.52/(1+6)]x 28.8 =  [0.2171]x 28.8 = 6.25 Bags

Sand: [0.2171] x 6  = 1.302  CuM.

Consumption of materials for 1 CuM of cement mortar (1:6):

Cement: 6.25 Bags
Sand:   1.302 CuM.

Now ,we actually need only 0.24 CuM of mortar for 1 CuM of brick work

Hence for 0.24 CuM of mortar , we shall need :
Cement: 6.25 Bags x 0.24 =1.5 bags
Sand:   1.302 CuM. x 0.24= 0.3125 CuM.

9.Summary II:
Consumption of materials for 1 CuM of Brickwork :
Cement: 1.5 bags
Sand:     0.3125 CuM.
Bricks: 541 Bricks

10.Now we are at the final lap:
Volume of brick wall:
5 x 4x 0.2 = 4 CuM

Therefore material consumption shall be:

Cement: 1.5 bags x 4 =  bags
Sand:     0.3125 CuM. x 4 = 1.25 CuM.
Bricks: 541 Bricks x 4 = 2164 Bricks

If the unit rates are known we can also find out total cost of the materials.

11.Assume that :

Bricks : INR 4200 per 1000. [ INR 4.2  per no ]

Sand : INR 4500 per Brass or 100 Cft.

[ INR 45 per cft or 45 x 35.29 = INR 1588 per cuM.]

Cement : INR 300 per bag of 50 Kg.

The material cost shall be as follows :

Cement:  bags@ 300 =       1800
Sand:     1.25 CuM.@ 1588 = 1985
Bricks:  2164 Bricks@ 4.2 =  9088

Total cost :1800 + 1985 + 9088

= INR 12,873

12. Now we can find out the materials cost per CuM  of  brick work :

12,873 /4 = INR 3218.25 per CuM of brick work

or 3218.25/35.29 = INR 91.19 per Cubic feet of brick work

Author’s note :

Hope you have understood the basics.

1.Remember , you don’t have to do all this calculation every .

Just memorize the unit cost i.e INR 3218.25 per CuM or INR 91.19 per Cubic feet of brick work .

As long as the material rates are the same, the cost shall be the same.

2. For those comfortable with spread sheets , once do this calculation in the spread sheet with proper formulae. Later , when any of the variable changes ,the moment you revise that figure, the entire computations shall be automatically revised.

Its really a fun.

believe me.

Happy journey on the path of estimations.

Laying Bricks for building success:

Overview:

Masonry comprises of a great part in the constitution of any building. It could be a RCC framed structure or a Load bearing construction, the masonry has a special place .

This series of posts bring the topic for discussion at an introductory stage.

Types of buildings:
Before starting discussions, let us see what are the various types of structures :

1.Framed structures:

The load of slab is taken by beams which transfer load to columns and columns transfer load to the footings or piles.

So in framed structures , Walls don’t carry any load except self weight.

Main purpose of walls in a framed structure is protection of the occupants & goods against nature

( wind, sun ,dust and rains) and of course to provide protection from  theft.

The walls are therefore known as Panel walls or Partition walls.

The load of slab is taken by beams which transfer load to walls and walls  transfer load to the wall foundation or piles.

Thus purpose of walls in a load bearing is two fold:

1.To transfer load to the wall foundation or piles.
2. To protect the occupants & goods against nature ( wind, sun ,dust and rains) and to provide protection from  theft.

Materials for masonry:

1.Red clay bricks
2.Fly ash bricks
3.Hollow concrete blocks.
4.AAC blocks: Auto-claved Aerated concrete blocks

5.Stone masonry:

Joining materials:
1.Lime mortar:
2.Cement mortar:
3.Chemicals :

Author’s note :

In subsequent posts , we shall review the following :

1. Need for breaking the joints

2.What is a ” frog ” and what is the purpose ?

3.What is the checklist for taking up brickwork ?

4.What is Raking ?

5.What are the advantages of a AAC masonry over conventional Brick work ?

6. What is a bond ?

7.What are the different types of bonds in use ?

8.What is a Stretcher ?

10. What are the quality checks for bricks ?

11.What are the quality checks for workmanship in masonry ?

We shall explore through all these issues one by one giving full focus to individual issue.

Till then ,

Good bye