Materials Estimations of A Building (MEB).
Materials Estimations of A Building (MEB). Our everyday life ought to depend on certainty which helps to eliminate disappointment in carrying out our day to day activities. On this very note, every building or structure project material must be well calculated. The calculation of these materials for a building project is termed material estimation of a building.
Every client (owner) of a building or construction project, want to know the quantity of materials that will be needed for such a project. However, the cost of such material will be multiplied by the quantity calculated to give the sum of money that will be needed for the purchase of the materials. Furthermore, this will help the client to prepare him/herself before the execution of the project. However, many estimators (quantity surveyors) has taken this as an advantage by giving client exorbitant estimate leading to excess spending on the side of the client. Hence this article is written to explain ways of estimating some building materials. On the other hand, it will help a client to foreknow the quantity of materials needed for a particular project before time.
Building Block Estimation – Materials Estimations of A Building. (MEB)
Before we start the estimation of blocks for a particular building project, there are important parameters we must have at hand. They are; (1) The building plan (2) Sandcrete block dimensions
The Building Plan – Building Materials Estimations. (BME)
The building plan contains all information about the building. It comprises of all dimensions such as the length and breadth of the building and all other compartments like rooms, main lodge, toilet, kitchen etc. addition of all these dimensions give us what is called perimeter of the building. Again, a building has two parts. The substructure and the superstructure
The Substructure – Materials Estimations of A Building. (MEB)
The part of the building that is below the ground is termed substructure. In other words, all works between the foundation and the damp proof membrane course (DPC) is called substructure. Meanwhile, the part of the building that is above the ground is called superstructure. It comprises of all works between the DPC and the roof level of the building.
However, the superstructure comprises of two-stage namely, the lintel level and the roofing level. The lintel level comprises of all works from the DPC to the top of all openings while the roofing level comprises of all works from the lintel level to the roof.
The DPC – Materials Estimations of A Building. (MEB)
The DPC of every structure or building solely depends on the topography of the plot of land where the building will be erected and the type of building to be erected. This will be determined by the designer of such plan. In a high leveled ground (free from water disturbance) the minimum DPC should be 600mm which is equivalent to three courses of block.
Important Dimensions to be noted.
The Height of a bungalow building from DPC (oversite concrete) to roof level = 3m = 3000mm =10fts = 12 courses of blocks plus the concrete lintel.
Bungalow building height from ceiling to finished floor =2.4m = 2400mm = 8fts
Height of a door opening in a building =2.1m =2100mm = 7fts.
Standard size of windows = 1200mm x 1200mm, 1800mm x 1200mm for rooms and main lodge while 600mm x 600mm, 900mm x 900mm, 600mm x 900mm are for toilets, bathrooms, and kitchen. Window sizes can be modified depending on the designer and purpose of such window in the building.
A nine inches block measure 18inch x 9inch x 9inch = 450mm x 225mm x 225mm
Six inches block measure 18inch x 6inch x 9inch = 450mm x 150mm x 225mm
A five inches block measure 18inch x 5inch x 9inch = 450mm x 125mm x 225mm.
Four inches block measure 18inch x 4inch x 9inch = 450mm x 100mm x 225mm
The most commonly used block among the above-mentioned blocks in Nigeria are; the 9inches block (Hollow), the 6inches block (Solid) and the 5inches block (Solid). Though, there is other nominal blocks and bricks size that will be published later.
Building Blocks Calculation.
Example 1: Calculate the number of blocks that are needed to complete a bungalow building of a total perimeter of 150m.
The perimeter given here comprises of all the linear dimensions of the building plan.
Perimeter = 150m = 150,000mm
Length of block = 18inch = 450mm
The number of blocks that will go round the building = total perimeter of building /length of block = 150000/450 = 333.33blocks. This is approximated to 333 blocks. This means that the first course of the block around the building will take 333 blocks. The number of blocks needed to raise the building from foundation bed to DPC taking DPC to be four courses will be: 333 x 4 = 1332 blocks are needed to the DPC.
Height of the building = 3m = 3000mm = 12 courses of blocks plus lintel. Therefor the number of blocks needed to raise the building from DPC roof level = 333 x 12 = 3996 blocks. Total blocks needed to complete the building excluding openings = 1332 + 3996 = 5325 blocks.
Opening (doors and Windows) Space.
The openings in this building are as follow:
Ten doors measuring 2100 x 900 each = 1890000mm2
Five windows measuring 1200 x 1200 each = 1440000mm2
Six windows measuring 600 x 600 each = 360000mm2
Area of a block = 450 x 225 = 101250mm2.
The number of blocks that need to be removed to create a door space = 1890000/101250 = 18.6 approximately 19 blocks. Again, the blocks that need to be removed to create a 1200 x 1200 window space = 1440000/101250 = 14.2 approximately 14blocks. Again, the number of blocks that must be removed to create a 600 x 600 window space = 360000/101250 = 3.55 approximately 4blocks.
Total opening blocks = 19 x 10 + 14 x 5 + 4 x 6 = 190 +70 + 24 = 284blocks
The number of blocks needed to complete the building = 5325 -285 = 5040 blocks. This is the number of blocks needed to complete the building with a total perimeter of 150m.