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


                                                       Dimensions of Brick Masonary


India Standard Brick Dimensions
The standard brick dimension is 190 x 90 x 90 mm (length x depth x height) as prescribed by BIS. 

Mortar thickness =10 - 16 mm

Cement used for brick masonry shall conform to IS 269 : 1976 or IS 455 : 1976 or IS 1489 : 1976 or IS 3466 : 1968 or IS 8041 : 1978 or IS 8043 : 1978.


An indent called frog, 1-2cm deep, is provided for 9cm high bricks. The size of frog should be 10 x4 x 1 cm. The purpose of providing frog is to form a key holding the mortar and therefore, the bricks are laid with frogs on top. It is not provided in 4 cm high bricks and extruded bricks.

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Dimensions of the brick
Dimensions of the brick

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 m2 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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