The latest trend in the building construction industry is the Do it yourself (DIY) approach, where homeowners tend to get themselves directly involved in simple building construction processes.
The first step in any building construction process is the estimation of the building construction materials and services. In this post, I would break down the cost estimation process for blocks(9inches), cement and sand of a simple floor plan.
The height of a building is generally specified in the architectural design but for this estimation, we shall assume a height of 3.125m
all dimensions in the simple plan below are in millimetres
https://harneyprojects.com/blog

BLOCKS –

Step 1 – Obtaining the Area of the block wall
We obtain the area of the wall by multiplying the height x the wall perimeter (The perimeter is a summation of the length of all the walls in the floor plan)
The perimeter of block wall = 24.3m
Area of the wall = 24.3 m x 3.125m
= 76m2
We then subtract the area of the Openings (windows and doors) from the wall area (Obviously, there won't be blocks laid in the window and door area)
The width of the window and doors is shown in the simple floor plan, the heights are generally specified in the architectural design. For this calculation, we shall assume a door height of 2.1m and widow height of 0.9m
Total openings (Area of windows + Area of doors) =9.5 m2
Total Area of Block wall = Area of the wall – Area of openings
= 76m2 – 9.5m2
=66.5m2
Step 2 – Obtaining the number of blocks required
Mathematically, 10 numbers of 9inch blocks make up 1m2 of the wall.

Let's prove it,
From the image, we can deduce that it’s only the width of the blocks (3inches, 6inches, 9inches) that varies, other dimensions remain constant.
The surface area of one 9inch sancrete block measuring at 225mm x 450mm
=0.10 m2
We now obtain the number of 9inch blocks in 1m2 of wall
Number of blocks in 1m2 = 1/0.10
= 10 blocks
Since we have established that 10 numbers of blocks make up 1m2 of the wall, then we obtain the number of blocks that would make up 66.5m2 of wall

Number of blocks required for our simple plan = Area of block wall multiplied by the number of blocks in 1m2
= 66.5 x 10
= 665 number of Blocks
We increase this by 10% to cater for bonding (Masons would cut some blocks in half to enable them to achieve adequate bond) and wastage during construction.
= 1.1 X 665
= 732 number of Blocks

Nice one...What about granite &sand? Following & preparing my questions... Thought u guys had gone into other ventures, is been long i see u people post...

Rubbiish:
Nice one...What about granite &sand?
Following & preparing my questions...
Thought u guys had gone into other ventures, is been long i see u people post...

Preparing others for posting,
We are still very much in the venture of building construction but we have been very very busy of late.

podosci:

Preparing others for posting,
We are still very much in the venture of building construction but we have been very very busy of late.

Good to know sir...

CEMENT –

Cement is mixed with sand in a mix ratio of 1:6 to make mortar used in bonding the blocks together. Cement is one of the most important building construction materials since its invention by Joseph Aspdin in 1824.
To estimate this, you need to understand the blocks and mortar
Blocks
For placement of mortar, we describe the parts of the block where the mortar is to be placed as (PERPEND AND BED)
Perpend- The Vertical side of the mortar between two blocks
Bed-The horizontal side of a block for placement of mortar
Mortar
Mortar is a mixture of cement and fine aggregate ( sand, stone dust) in a mix ratio of 1(cement): 6 (sand). The
The mortar is going to be 25mm thick for both the perpend and the bed.
Mathematically and from Experience, A mortar made from one 50kg bag of cement can be used to bond an average of 48 number of 9inch blocks and 60 number of 6 inches blocks

Total number of cement required = Number of blocks/number of blocks to be bonded by one bag
= 732/48
= 16 bags of cement

SAND –

This is easily obtained from the mix ratio of 1: 6 which can be simplified as 1 part of 6 cement to be mixed with 6 part of the sand
We would then obtain the volume of cement to be used and multiply by 6
One bag of cement weights 50 kg
Volume of cement = 50kg x 16
=800kg
Volume of sand required = 800 x 6
=4800kg of sand
Sand is usually purchased in tonnage in Nigeria, of which 1000kg = 1 ton
Therefore, Volume of sand required = 4800/1000
=4.8 tons of sand

In summary, we would require 732 blocks, 16 bags of cement and 4.8 tons of sand for the simple floor plan above.

@podosci, very helpful info, thank you.

Can you please share the tips of how to calculate cement needed for concrete flooring?

Plea