Easily Way on How To Estimate Numbers Of Blocks Required For Your Building Project From A Simple Plan Layout

              It’s natural for one to wonder how many blocks are in a wall. The simplest and surest way to obtain that number is to count them all, but that could take a long time, and it isn’t of any help for someone who wants to know how many blocks are needed to build a wall.
Fortunately, basic arithmetic can be used to calculate a fairly reliable estimate to satisfy curiosity as well as practicality. Does this Spark an idea?

In this article, I will unveil to you the secret on how to estimate on your own from a building plan layout, the number of blocks that would be consumed in a building construction.
For this particular lesson, we are going to use the plan layout above (fig 1.1) as our case study.
NOTE:
• The nature of the soil for this project is a very good and stable soil.
• The type of foundation used is a strip foundation.
• 9 inches blocks will be used in the foundation since its stable.
• 6 inches blocks will be used after the floor slab (DPC) to roof level.
• The length of a block ( 6inches or 9inches is 450mm ) = 0.450m
• The width of 6 inches blocks is 150mm = 0.150m
• The width of 9 inches block is 225mm = 0.225m
mm = millimeters
m = meters
m3 = cubic meter

Generally the blocks laid from foundation to DPC level is 4 courses/levels, from DPC to the base of window is another 4 courses, from base of window to lintel is 5 courses, after your lintel, there will be another 2 courses followed by your roof beam. This will make a total of 15 courses.

Now with these parameters above let’s calculate the 9 inches blocks that will be laid in the foundation

• From the building plan above (fig. 1.1 ) The total length of the foundation trench is :
4.8m+3.9m+4.8m+3.9m =17.4m
Calculating the required number of standard construction blocks:
Below provides a very fast, simple way to find the answer.
From the table above the number of 9 inches blocks needed for the foundation wall will be:
17.4m / 0.45 = 38.67 » 39 blocks
Since the foundation would be 4 courses, we will have:
39 blocks x 4 courses = 156 blocks.
So therefore, the foundation will take 156 blocks (9 inches).

Add 10% for wastage 10/100 x 156=15.6» 16 blocks so no’s of block is 156+16=172 blocks (9 inches).

• USING AREA METHOD
Length of foundation wall = 17.4m
Height of foundation wall = 0.9m
Area of foundation wall = 17.4m x 0.9m = 15.66m2
To get the numbers of blocks we will multiply by 11(since11 block is in 1m2)
i.e = 15.66m2x 1.1 = 172.26» 172 blocks

Furthermore, from the DPC to the roof level excluding lintel and roof beam, we have a total of 11 courses.

The numbers of blocks will be: 39 blocks x 11 courses = 429blocks+43 blocks=472blocks (6 inches) neglecting window and door openings

USING AREA METHOD
Length of block wall = 17.4m
Height of structure excluding lintel and roof beams = 2.475m
Area of entire block structure = 17.4m x 2.475m = 43.07m2
To get the numbers of blocks we will multiply by 11(since11 block is in 1m2)
i.e 43.07m2x 11 = 473 blocks

Now we need to consider the windows and doors in the plan layout, taking into consideration that the height for windows and doors is 4ft and 7ft respectively.
From the plan, we have:
• 3 windows of 1.5m by 1.2m and
• 1 door of 0.9m by 2.1m

AREA OF WINDOW
1.5m x 1.2m =1.8 m2
To get the numbers of blocks we will multiply by 11
i.e 1.8 m2x 11 = 19.8 » 20 blocks
For 3 windows it will be 20 blocks x 3 = 60 blocks
Therefore the 3 window will take approximately 60 blocks

AREA OF DOOR
0.9m x 2.1m = 1.89 m2
To get the numbers of blocks, we will multiply by 11
i.e 1.89 m2x 11 = 20.79» 21 blocks

Total blocks in window and door area will be:
60 blocks + 21 blocks = 81 blocks
Therefore the number of 6 inches blocks from DPC to roof level will be
473 blocks – 81 blocks = 392 blocks

So therefore the total number of blocks needed from foundation to roof level is:
172 blocks (from foundation wall) + 392 blocks (from DPC to roof)
= 564 blocks
NOTE:
This difference will be accounted as wastages due to breakage, since calculations are not 100% true