Brick masonry measurement
Brickworks are measured in cubic meters unless otherwise specified.
Dimensions will be accurately measured to the nearest 0.01 m, i.e. 1 cm. Areas will be calculated to the nearest 0.01 square meter, and cubic materials will be worked to the nearest 0.01 cubic meters
Brickwork will be measured separately in the following steps:-
From foundation level to Ist floor level.
floor one level to floor two level.
Between both specified floor levels above the floor two levels.
Additional work on specified dimensions will be ignored.
Dimensions of brick masonry
Brick can be modular or non-modular.
While the use of modular bricks/tiles is recommended, non-modular bricks may also be used where it is specified.
Non-modular bricks/tiles of sizes other than those mentioned below the table may also be used, where specified.
The sizes for the two types of will be as per the table below.
Type of Bricks/ Tiles | Nominal Size mm | Actual Size mm |
Non-modular bricks | 229 x 114 x 70 mm | 225 x 111 x 70 mm |
Non-modular tile bricks | 229 x 114 x 44 mm | 225 x 111 x 44 mm |
Modular Bricks | 200 x 100 x 100 mm | 190 x 90 x 90 mm |
Modular tile bricks | 200 x 100 x 40 mm | 190 x 90 x 40 mm |
Composition of Brick : -
Alumina:- A good grade brick contains 20–30% alumina. The excess of alumina in the soil forms a brick crack and wraps upon drying.
Silica:- In general, bricks are made with 50–60% silica in it. The excess of silica in the brick makes the brick brittle.
Lemon:- Brick contains 0.8–2% of lime. Excess of lime in the brick may melt and deform during burning.
Other components:- Magnesia, sodium, potassium, manganese and iron oxide.
Brick calculation for brick masonry rate analysis
Size of actual brick =190 mm x 90 mm x 90 mm
Volume of 1 brick with mortar = 200 x 100 x 100 (10 mm mortar thickness on all sides)
= 0.2 m x 0.1 m x 0.1 m (as 1m = 1000 mm)
Volume of 1 brick with mortar = 0.002 cum (㎥)
Thus, No. of bricks required for 1 cum (㎥) = 1 / 0.002 = 500 Nos.
Brick required for 10 ㎥ = 500 Nos (1 cubic meter = 500 pieces of brick) x 10 cu.m
So, for 10 cu.m brick work requirement = 5000 nos. brick required
Cement and sand calculations
1.Calculation of cement
Volume of bricks without mortar㎡
1 brick volume without molar = 190 mm x 90 mm x 90 mm
= 0.19 m x 0.09 m x 0.09 m
The Volume of 1 brick without mortar = 0.001539
The volume of 500 bricks without mortar = 500 nos. x 0.001539 ㎥
Volume of bricks without mortar for 1 ㎥= 0.7695
= So, required amount of cement mortar = 1㎥^{ }- Volume of bricks without mortar.
Cement mortar = 1 ㎥^{ } - 0.7695
Required amount of cement mortar = 0.2305 ㎥ (wet state) = 0.2305
After adding water to the mortar mix, it bulks and reduces the volume by 33% during wet condition. In order to calculate the dry volume of cement & sand or Brick mortar add 33% of extra volume to it.
Dry volume of mortar = Wet volume of mortar x (1+0.33) [33% of volume]
Dry volume of mortar = 0.2305 cubic meter. x 1.33 = 0.306565
Cement mortar ratio is 1: 3 (1 cement: 3 fine sand)
The required quantity of cement quantity on brickwork
= 0.306565 ㎥ x 1 / (1 + 3)
= 0.3065 x 0.25
= 0.07664125 cu.m.
Cement (k.g) = Volume x Density of Cement
= 0.07664125 cu.m. x 1440 ( as density of cement =1440 kg / ㎥)
= 0.07664125 x 1440 = 110. 363 kg cement required
= 110.363 / 50
= 2.20 bags (weight of one cement bag is 50 k.g)
For 10 cu.m, brick work requirement = 2.20 bags x 10 cu.m = 22 cement bags
2. Calculation of Sand
Amount of sand required = 0.306565 x 3 / (1 + 3)
= 0.2299 Cu.m.
For 10 cu.m, brick required = 0.2299 Cu.m x 10 cu.m. = 2.299 ㎥
Deduction of Brick Masonry
A minimum area is defined for deduction of an opening, zero, or both, such an area shall refer only to the opening or void within the measured space.
A minimum area is defined for the deduction of an opening, void, or both, such areas shall refer only to the opening or void within the space. Unsatisfied materials (ie, joists, lintels, beams, rafters, posts), girders, purlins, corbels, trusses, steps, etc.); Up to 0.1 m2 in section.
Opening upto 0.1 m^{2} in area
Wallplates, bed plates and slab bearings, chajjas and where the thickness does not exceed 10 cm and and the bearing does not extend over the full thickness of the wall.
Cement concrete blocks as for hold fasteners and holding down bolts.
Pipes,iron fixtures, such as wall ties, pipes up to 300 mm diameter and holdfast for doors and windows and chases of section stretch of not more than 50 square meters.
Rate Analysis of Brick Masonry
Brickwork with best available local bricks in foundation and plinth in cement mortar 1:3 (1cement : 3 fine sand) | |||||
Cost for 10.00 Cu.m | |||||
No. | Description | Qty | Unit | Rate | Cost |
A | Labour Charges | | | | |
1 | Mate | 4 | Day | 350 | 1400 |
2 | Mason | 4 | Day | 700 | 2800 |
3 | Helper | 8 | Day | 500 | 4000 |
4 | Coolie | 2 | Day | 350 | 700 |
B | Material | | | | |
| Bricks (Size of brick = 190 mm x 90 mm x 90 mm) | 5000 | Day | 5 | 25000 |
| Wastage of brick 5% Extra | 5% | | | 1250 |
| Cement | 22 | Bag | 320 | 7040 |
| Wastage of cement 2% Extra | 2% | | | 140.8 |
| Sand | 2.3 | Cu.m. | 1362 | 3132.6 |
| Wastage of sand 2% Extra | 7% | | | 219.28 |
C | Scaffolding 1% Extra | 1% | | | 365.63 |
D | Transportation Cost 1% | 1% | | | 365.63 |
E | Other Charges 2 % Extra | 2% | | | 731.27 |
F | Add for Water Charge @ 1% on Items Marked | 1% | | | 365.63 |
G | Add for Contractor’s Profit @15% on Items Marked | 15% | | | 5484.51 |
| Cost of 10.00 Cu.m. | 52995.36 | |||
Cost of Cu.m. | 5299.54 | ||||
Round off Cu.m. | 5300 |
Calculation of brick masonry for labour
As per calculation of rate analysis per cubic meter in labor consumption. As per our experience or CPWD book, this book is public for easy calculation of requirement, rate analysis etc. by Central Public Works Department, Government of India.
As CPWD Mate per cu.m. 0.4 of days Mate and Mason, Helper per cu.m. 0.8 of day, coolie for water curing per cu.m. 0.4 of day.
Waste in brick masonry
All measurements of cutting unless otherwise stated or deemed to include waste.
Like brick masonry, 5%, cement 2%, and sand 7% wastage as per IS code allowance.
Additional work calculations in brick masonry rate analysis
Scaffolding 1% additional.
Transportation cost 1%.
Other charges 2% extra (electrical, and site additional expenses).
Add water charge @ 1% on marked items.
Add @ 15% for contractor benefits on marked items.
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