# How to calculate number of blocks for your building project in 2 simple steps.

What is the number of blocks required to complete this building?This is a common question asked by prospective home owners especially after the building design phase.It is advised you use trusted professionals for your building project. This saves you time and money. However, if you are taking charge of material procurement or just wish to confirm number of blocks required for your project, these 2 simple steps outline the process outlines the steps you need to take. A simple 1 bedroom apartment is used in this case for clarity.

These are the two basic steps: Step 1: Calculate wall areas. Step 2: Divide total wall area by area of one block.

Step 1:

To calculate wall areas, we will calculate the total length of walls and multiply by wall height.

Area=Length x Breadth, In this case since we are dealing with height,

Area=Length x Height

Calculate Length: Looking at figure 1,we take length of vertical walls first(from left to right), then horizontal walls(from top to bottom)

Wall 1= 8000mm , Wall2=7755mm, Wall 3=3675mm, Wall 4=4100mm, Wall 5=3900mm, Wall 6=7950mm

Wall 7=3525mm, Wall 8=5975mm, Wall 9=5600mm, Wall 10=4425mm, Wall 11=4200mm

Ground Floor Plan

Sum of all wall length is=59,105mm.

Use height of wall at 3000mm.

Rough wall area (Wall area including openings) =59105mmx3000mm= 177,315,000mm

Remember we have some wall openings at the entrance, doors and windows. We have to subtract areas for these to get the actual wall area:

We have 6 doors with measuring 900mmx2100mm: 6x900mmx2100mm= 11,340,000mm*2

We have 8 windows measuring 1200mmx1200mm: 8x1200mmx1200mm= 11,520,000mm2

We have 1 window measuring 600mmx600mm: 1x600mmx600mm= 360,000mm2

We have 1 opening measuring 3300mmx2100mm: 1x3300mmx2100mm= 6,930,000mm2

Opening area: (11,340,000+11,520,000+360,000+6,930,000) mm2= 30,150,000mm2

Subtract opening area from the rough wall area:

Actual ground floor wall area:(177,315,000-30,150,000) mm2= 147,165,000mm2

Area of foundation walls:

Also,remember we have a foundation. The foundation area depends on the number of courses laid. For this building, we use four courses of block wall as foundation (Strip foundation). This is roughly 900mm high.

We simply multiply the perimeter of walls we got in step 1 by the height of the foundation wall. Area is still length x height. But now the height is 900mm.

Area of foundation wall: 59105mmx900mm=53,194,500mm2

Total wall area = Ground floor wall area+Foundation wall area

=147,165,000mm2+53,194,500 mm2= 200,359,500 mm2

Step 2:

Area of one block is 225mmx450mm= 101,250mm2

Number of blocks is total wall area divided by area of one block:

Hence, number of blocks is:200,359,500/101,250= 1978.86 blocks

That’s approximately1,980 blocks. You may want to add a certain percentage for breakages and off-cuts. If you use good quality vibrated blocks you only need to add a little.

Wish you success on your building project.Kindly mail us on info@nigerianhouseplans.com if you need clarifications. Thank You!

1. Winnerz

Thank you for this information, it is very useful.
Pls how did you get 5600mm for wall 9

• nighouseplans

Dear Winnerz, wall 9 is 4425 + 1175 mm giving 5600 mm.

2. Sunday

Thank so much very interested

3. Smith Mulango

Please i will like to know how wall 9 wall calculated to be 5600?

• nighouseplans

Dear Smith, we don’t quite understand what you mean.

• Troy

1,980 blocks for foundation or to the window level cos I dont understand

• nighouseplans

Dear Troy, this is for everything… The entire building including foundation.

4. Olanipekun Kehinde Hassan

Please I want to calculate 5 bedroom Duplex

• nighouseplans

Dear Hassan, Kindly use the method highlighted or you can send the perimeter of the building and we can give you a rough idea of the number of blocks you need.

• victor

A perimeter wall of 100m x 130m.
the measurement of one block is 20cm x 20cm x 40cm.
how many blocks can be used?

• nighouseplans

Hi Victor, We assume you meant length is 130 meters and breadth is 100 meters. If so the total wall length is 460 meters.
If we divide by one block, we have:

460m/0.4m=184 blocks per course (per layer of block).

The total number depends on how high you want to go. If 12 blocks high simply multiply by 12:

184×12= 2208 blocks.

5. Malachy Iroro Emeje

Good morning. Pls in clear terms, how do calculate for the estimate of works for a storey block of 4flats( components of 2no. 3- bedroom flat and 2no. 2- bedroom flat respectively.

• nighouseplans

Good morning, in summary calculate the total area of block work and divide by the area of one block (.45mx.224m)

Or calculate the length of one course of block work, multiply by the number of courses then subtract the number of blocks for doors and windows.

6. Ngum Godlove tandah

Thanks verymuch, i need more help in house calculation ,tiles, n sand,cement

• nighouseplans

Dear Ngum,for floor tiles, simply calculate total wall or floor area by multiplying the length and the breadth.sand and cement depends on the mix and will be attended to in a later post.

• Emmanuel Limbu

Thank you

• nighouseplans

You’re welcome

7. Oziomz

Thank you so much

• nighouseplans

You’re welcome

8. Eben

What if I want to know the number of blocks for the first course during the foundation

• nighouseplans

Dear Eben, in this case calculate the perimeter and length of walls inside and divide by . 45m which is the length of one block

Quite explanatory.
Thanks so much

10. nigerhouseplans,

Thanks for the article, I like the flow and detailed explanation. This will be helpful not just to those in the building industry but to clients as well.

Keep up the good work!

• nighouseplans

Thanks intellectArchitects

11. Opalana Julius

This is a good one

• nighouseplans

Thanks Julius

12. Bright Owenvbiugie

Thank you so much boss this is well understood

• nigerhouseplans

You are welcome bright.

I really appreciate your explanations. You are bless

• nigerhouseplans

Thanks for the compliment Taiwo.

That was a lovely detail explanation. At least it will really help in giving a client the back up to the number of blocks used on the site.

• Akinlabi Abass

Need a quantity surveyor chat me up

• Legendary

Good evening sir,I need service or help of quantity Surveyor

• nighouseplans

• nigerhouseplans

15. Okike Earnest

I really learnt alot. Thanks sir.
Can you give explanation on how to calculate roofing sheet

• nigerhouseplans

Thanks for the compliment Okike, we may do this on a later post.

16. Iseoluwa

I love this explanation

• nigerhouseplans

Thanks for the compliment Iseoluwa.

17. John Chukwuebuka Okeke

Thanks a lot
Great Builders

• nigerhouseplans

You’re welcome Mr.John.

18. Azubuike ibe Christopher

Thanks
I have a more easier step.
Solution:
Total length of wall = 59.105m
Length of a block = 0.45m
Total of blocks for each course: 59.1050.45 = 131blocks approximately
Height of the wall 3m height of a block = 13.3courses + 4courses substructure = 17.3courses from fdn to roof level
Therefore, total number of blocks required =
Total number of blocks for each course multiply by the total number of courses.
i.e 131*17.3 = 2267blocks minus the blocks in the openings

Openings as calculated = 30.150m
Area of a block = 0.45*.225 = 0.10125m
Total blocks in the openings 30.1500.10125 = 298blocks

i.e 2267 — 298 = 1969blocks very close with just difference of 1980 — 1969 = 11blocks

• nigerhouseplans

Thanks Mr.Christopher.

• EGBUNU DUNCAN ONALO

Good afternoon sir, plz. I’ll need a 3 and 6 bedroom duplex plan that includes the calculations for the number of blocks, cement, rods, roofing materials, labor and other things that it’ll take to get the actual amount or close to it for its starting to finish.

• nigerhouseplans

Dear Duncan, this is a bill of quantities or material list. We can advise on a rough estimate prior to purchasing a plan but the BoQ may be done after plan purchase if required. Thanks.

19. Waxco Consult & Developers

Wow! Thanks so much for this information, it’s indeed a refresher, Bigups Nigerplans

• nigerhouseplans

Thanks

20. Lovly very very good

• nigerhouseplans

21. Israel

Whoa. This was very helpful. Thanks so much

• nigerhouseplans

You’re welcome Israel.

22. Azeezat

Thanks the article is really healful

• nigerhouseplans

You’re welcome Azeezat.

23. Thanks for sharing good information, how to produce concrete blocks with block making machine.

I really appreciate for the simple enlighten on buildings project.I am builder.

• nigerhouseplans

You’re Welcome Mr. Kayode

25. Ebenezer

• nigerhouseplans

You’re welcome Mr. Ebenezer.

26. Emmanuel Gabriel

These process review the details knowledge on how to calculate the amount of block in a giving project.thanks

• nigerhouseplans

Thank You Emmanuel.

27. Henry moses

Senior mens to study building is not an easy thing; but we thank God for giving us understanding always, pls if u dont know something ask and it shall be giving unto u

28. Abdulsalam Abideen

Pls what if we are to calculate the amount of blocks to be used for a wall
Maybe for 1 8000mm
Pls

29. daniel mark