How to build a concrete block water tank

 

Water Tank may be constructed using Concrete Blocks Using Following Construction methodology.

1- First of all we should work calculate size of water tank as per required capacity.

Suppose we want to construct 50 thousand US Gallon capacity tank on Ground surface using block masonry with cement sand mortar (1:3) ,now the main thing is how much Length and width should be adopted for the construction of water tank. It is needed to understand that  if we increase the area by increasing the length and width of tank it's depth will be decreased and if we decrease the size or area of tank its height will be raised.

Now we will equate the height  of wall with reasonable thickness of wall so let's have some calculations regarding suitable construction of water tank.

Capacity of water tank = 50000 US-Gallons

Volume of Water Tank As per 50000 US-GALLONS= (50000x3.78)/28.32= 6674 Cft

Volume of water tank = Length x Width x Depth

Say we have feasible size of 40 Ft x40 Ft

6674Cft =  40Ft x40Ft x Depth

Depth     = 4Ft-2 Inch

Next Step is Calculation of Horizontal Pressure Using following formula

P = (w.H.H)/2

Here    w= Density of water in Pound/Cubic Foot

H= Depth of water in Feet

P= Horizontal Pressure in Pound/ Rft of wall

Putting the available values

Pressure =( 62.4x4.17x4.17)/2 = 543 Pounds

 

We know that maximum pressure acts at H/2 OR H/3 So Adoption value of H/2 we will proceed for further steps to decide wall design using concrete blocks.

We will design concrete blocks wall using maximum pressure at H/2 .

Maximum Pressure = Weight of wall

543 Pounds = Length x Width x Depth x Density of Block Work

543 = 1ft x Width x 4.17 Ft x 130 Pound/ Cft

Width = 1 Ft

Factored Width of wall will be 2 Times of wall width at Maximum Pressure

Width = 2 ft.

2 ft width will be continued up to the depth of 2 ft and then it will be gradually decrease to produce 1 ft width at top of wall .

The Ground bearing capacity has been found as .65 Ton/Sft

So we can check feasibility / Suitability of Bearing capacity according to the weight of water tank.

According to following designed data

1- Excavated depth to approach the ground surface where bearing capacity is .65 Ton /Sft is 3 Ft.

2- Supply and lay Pcc (1:3:6) concrete 3" thick

3- Supply and lay Rcc (1:2:4) concrete 6" thick

4-Construction of block masonry (1:3) using Cement sand mortar as shown in figure. A.

5-Supply and apply cement sand plaster (1:2) 3/4" thickness complete in all aspects.

Check feasibility of bearing capacity of ground at  block wall line

 

Weight of wall = 1 x 2x2x130          = 520 Pounds

    Weight of wall =1x(1+2)/2x130    =195 Pounds

Weight of PCC = 1x2x.25x140         =70 Pounds

Weight of RCC = 1x2x0.5x140         =140 Pounds

 Total Weight      = 925 Pounds per 2 Sft under wall area

So Load per SQ.FT In Pounds =   462.5 Pounds Per Sft

So Load per SQ.FT In Tons =   462.5 /2240 = 0.2 Ton/Sft

So it is very safe load against bearing capacity of ground

Now we will make a safety check in water portion  

Weight of PCC = 1x2x.25x140         =70 Pounds

Weight of RCC = 1x2x0.5x140         =140 Pounds

Weight of water = 1x1x62.4x4.17     =260 Pounds

Total Weight in pound/Sft     = 470 Pounds per Sft

Total Weight in Ton /Sft     = 470 /2240 = 0.2098 Ton/Sft

So it is also very safe load against bearing capacity of ground.

Now we can start construction in following ways

1- Excavation of soil including shifting of surplus soil having lead of 500 Ft and Lift up to 7 Ft complete in all aspects

2- Provision of 100 % compaction including cut and fill up to 6 inch using road rollers complete in all aspects.

3- Provide and lay PCC (1:3:6) 3 inch thick using good class of cement ,sand , crush and water complete in all aspects

4- Provide and lay RCC (1:2:4) 6 inch thick using good class of cement ,sand , crush and water .Use 1/2" dia bars @ 9" c/c both ways and complete in all aspects.

5-Construction of Block wall using cement sand mortar (1:3) Complete in all aspects.

6-Supply and applying of cement plaster (1:2)  3/4" thick using good class of cement and sand ,complete in all aspects.

7- Supply and lay Pcc(1:2:4) concrete on wall and bed joint in 45 degree angle slope including float finishing and use of admixture to gain water tight concrete.

Overhead water tank construction procedure

Construction of overhead water tank should be according to specific procedures to control its load and possible leakage problems in building. Details of construction procedure is as follows having two phases 

A-Design phase procedure 

B-Construction phase procedure 

Firstly we will discuss design phase procedure.

1- Adjust size according to capacity of water tank, suppose required capacity is 2000 Gallons and size according to this capacity can be calculated as 

Volume of tank in Cft = (Capacity in Gallons x 3. 78) /28.32 

=(2000x3.78)/28.32 = 266.95 Cft

Now we know that 

Volume of tank in Cft = Length x width x Depth 

Here taking consideration for square tank we should also match the size (Length x Width) of water tank according to span of load bearing walls or avail columns spans. This span should be near external walls. 

266.95 Cft = 8ft x 8ft x Depth of water 

Depth of water = 4.17 ft say 4ft-2 Inches. 

Adding free board of 6 inches 

Total depth of water tank will be 4ft-8 inches

Suppose we have a available load bearing wall span of 8ft x 8ft. 

2- Here we will raise all walls of lower span of 8ft x 8ft up to the height of 3 ft to 4ft or planted columns may also be raised by providing 4 equal length beam in slab.

3- Base slab size can be obtained by adding 6 inch thick RCC load bearing walls and 2 inch wide cavities along with 4.5 thick walls on external side of tank. 

Cavities will provide insulation to keep water cool in summer and warm in winter. 

So the base slab size= clear span +2 load bearing walls+2 cavities?+2 walls 4.5 inch wide.

Putting values= (8)+(2x.5ft)+(2x.16ft)+(2x.375ft)+ finishing margins of. 75 inches on 4-faces of walls (4x.06)= 10.32 ft say 10ft-4inches

4- Considering 4 planted columns sized 12inch x 12inch and height of 3 ft with 4 beams having width of 14 inches (To accommodate load bearing wall of 6 inch+2 inch cavity +4.5 inch wide brick wall and 1.5 inch finishing margin. Slab thickness should be 8 inches having concrete cover of 1.5 Inches on top and bottom of slab, using ½” Dia bars @6 inch c/c both ways at top and bottom of slab. And same bars with same spacing will be provided in walls. Top slab will be 5 inch thick having 3/8 “ Dia bars @ 6” c/c both ways single mesh. 4 columns will be provided with 8 nos of ½ “Dia bars and stirrups of 3/8 “ Dia bars will be provided at 9”c/c. 

Secondly we will discuss construction phase procedure in following steps. 

1- Construction of 4 planted columns sized 12inch x 12inch using Rcc (1:2:4) and 8 vertical main bars of ½ “Dia plus 3/8 “ Dia bars stirrups @9” c/c, Use water tight shuttering along with proper bracing complete in all aspects. 

2- Construction of Rcc (1:2:4) for 8  inch thick slab (using 1/2”Dia  main bars@ 6” c/c both ways on top and bottom) and side Beams sized 14 inch width x 9 inch depth having 3 nos bottom bars of ¾ “ Dia and stirrups of 3/8” Dia bars @ 6”c/c on entire span of all beams. 

3- Construction of Rcc (1:2:4) load bearing walls 6 inch wide and 4ft-8inch high using ½”Dia bars @6”c/c both ways and on both faces of wall, use 1” concrete cover, use good class of shuttering along with complete bracing, Use water stopper on construction joint at base slab and load bearing walls. 

4- Construction of Brick walls 4.5 inch thick using cement sand mortar (1:4) spacing 2 inch away from load bearing walls to create cavity for insulation, applying of cement plaster (1:4) ¾” thick complete in all aspects. 

5- Construction of Rcc (1:2:4) slab 5 inch thick including shuttering and scaffolding maintaining slopes for rain water, use 3/8” Dia bars @6”c/c both ways. 

6- Supply and fixing of water supply pipes near bottom of slab including all type of valves, overflow pipe, complete in all aspects. 

7- Supply and applying of chips plaster ¾ “ thick on bed and walls of water at internal side maintaining required slopes. 

8- Supply and fixing of manhole in top slab of water tank including fixing of L-shaped angle iron complete in all aspects. 

9- Supply and fixing of motor pumps for pumping of water in case of low pressure in main supply line. 

10- Supply and fixing of drain pipe at bed of water tank to empty, cleaning and repair activities. 

11- Provision of electric connections for installation of motor pumps complete in all aspects. 

How to calculate cement, sand and aggregate quantity in concrete in Cft

There are different concretes having different ratios and strength. 

Materials of concrete may be calculated in following way for all type of concretes. We are explaining with following example. 

Calculate materials of concrete (1:2:4) having water cement Ratio of 0.45 to pour RCC slab sized 100 ft x 50 ft and 6 inch thickness. Admixture should be added @2 %. 

Calculations. 

Wet volume of concrete = Length x Width x Thickness 

=100x50x6/12= 2500 Cft. 

Dry Volume of concrete =Wet volume x Drying factor 

Note, Drying factor used for concrete is 1.54

Dry volume of concrete = 2500x1.54= 3850 Cft

Cement in bags = (Ratio of Cement x Dry Volume) /(Sum of Ratios). (Volume of one cement bag). 

1-Cement in Bags =(1x3850)/(1+2+4).(1.25)= 440 Bags

2-Sand in Cft  = (Ratio of Sand x Dry Volume) /(Sum of Ratio) 

=(2x3850)/(1+2+4)= 1100 Cft

3-Crush stone in Cft  = (Ratio of Crush x Dry Volume) /(Sum of Ratio) 

=(4x3850)/(1+2+4)= 2200 Cft

4- Water in Liters = Weight of cement in kgs x Water cement ratio= Liters

= 440 Bags x 50 kg x. 45 = 9900 Liters

5- Admixture = Weight of cement x % part of admixture 

= 440x50x2/100= 440 Liters

How to calculate water tank capacity in gallons

 

Capacity of any water Tank may be found using following basic formula.

Capacity in Gallons = Volume of Tank X 7.4813

1 Cubic Foot volume may contain 7.4813 US Gallons

Rectangular Tank = Volume x 7.4813 US Gallons

                              = Length x Width x Depth x 7.4813

Suppose we have water tank having size of 10 ft x 5ft x 5ft

                               = 10X5X5X7.4813= 1870.32 Gallons

 

   Cylindrical Tank  = Volume x 7.4813 US Gallons

                                 =( πxDxD)/4 x Height x 7.4813

Suppose we have a tank whose diameter is 10 ft and height is 7 ft .

                                  = (3.14 x 10x10) /(4) x7 x7.4813 = 4110.97 US Gallons.

Square Tanks  = Volume x 7.4813 US Gallons

                                 =Length x Width x Height x 7.4813

Suppose we have water tank having size of 10 ft x 10ft x 5ft

                                  = 10x10x5x7.4813 = 3740.65 US Gallons.

Polygon Shape Tank Capacity         =( N.a^2)/4. Cot ϴ x Height x 7.4813

 

Here    N = number of sides

             a = Length of each side

            ϴ = 180 / Number of Sides

            Cot = Cos / Sin

Suppose we have a water tank which has octagonal base having 3 ft length of each side and height is 10 ft.

 

= 8 x (3^2)/4 xCos (180/8) /Sin (180/8) x 10 X 7.4813

= 18X2.4142X10X7.4813=  3251.04 US Gallons

9 INCH BRICK WALL CONSTRUCTION COST

 

BRICK WALL COSNTRUCTION COST INVOLVES THREE ACTIVITY COST.

1- COST OF BRICKS

2-COST OF MORTAR (1:4)

3-COST OF LABOR

WE CAN CALCULATE  COST PER SQ.FT

A- COST PER SQ.FT

1- COST OF BRICKS

No of Bricks = Area x Wall thickness x 13.5

NO OF BRICKS = 1 x 1x 9/12 x 13.5 = 10.125 Nos @ 8 Rs/ no = 81 Rupees /Sft

2-COST OF MORTAR (1:4)

Quantity of cement = Vol of wall x .3x 1 /  (Sum of Ratio)(Vol of Cement Bag).

Quantity of Sand =  Vol of wall x .3x 4 /  (Sum of Ratio)

 

Quantity of Cement = (1x 1x0.0.75)x0.3 x1 / (1+4),(1.25) =0.036 Bags @ 600 Rs/Bag=21.6 Rs /Sft

Quantity of sand  = (1x 1x0.75)x0.3 x4 / (1+4)               =0.18 Cft @ 40 Rs/Cft = 7.2 Rs/Sft

3-COST OF LABOR

1 Mason and 2 Labor Can do 100 Sft of Brick wall

Single Day Cost of Mason = 1@ 1200 / (90 Sft) =13.33 Rs/Sft

Single Day Cost of 2-Labors =2 @ 700 /(90 Sft) =15.55 Rs/Sft

Total cost = ( 81+21.6+7.2+13.33+15.55 ) = 138.68 Rs/Sft

Cost may be calculated around the world using material and labor cost as per local rates. Rates are Indicated in Yellow highlights.

4.5 INCH BRICK WALL CONSTRUCTION COST

 

BRICK WALL COSNTRUCTION COST INVOLVES THREE ACTIVITY COST.

1- COST OF BRICKS

2-COST OF MORTAR (1:4)

3-COST OF LABOR

WE CAN CALCULATE  COST PER SQ.FT

A- COST PER SQ.FT

1- COST OF BRICKS

No of Bricks = Area x Wall thickness x 13.5

NO OF BRICKS = 1 x 1x 4.5/12 x 13.5 = 5.0625 Nos @ 8 Rs/ no = 40.5 Rupees /Sft

2-COST OF MORTAR (1:4)

Quantity of cement = Vol of wall x .3x 1 /  (Sum of Ratio)(Vol of Cement Bag).

Quantity of Sand =  Vol of wall x .3x 4 /  (Sum of Ratio)

 

Quantity of Cement = (1x 1x0.375)x0.3 x1 / (1+4),(1.25) =0.018 Bags @ 600 Rs/Bag=10.8 Rs /Sft

Quantity of sand  = (1x 1x0.375)x0.3 x4 / (1+4)               =0.09 Cft @ 40 Rs/Cft = 3.6 Rs/Sft

3-COST OF LABOR

1 Mason and 2 Labor Can do 100 Sft of Brick wall

Single Day Cost of Mason = 1@ 1200 / (100Sft) =12 Rs/Sft

Single Day Cost of 2-Labors =2 @ 700 /(100 Sft) =14 Rs/Sft

Total cost = ( 40.5+10.8+3.6+12+14) = 80.9 Rs/Sft

Cost may be calculated around the world using material and labor cost as per local rates. Rates are Indicated in Yellow highlights.

Importance of Time Management

 Time management is life management because the second name of time is life and there is no life if there is no time.

Time management is planning for economical execution of tasks within designed time line. 

Time management importance can be narrated by some lines as under. 

1_Time management provides sequence and ease in life to complete daily tasks in required time lines.

2_Time Management limits the efforts according to availability of resources and also motivates about what is excessive and what is missing to achieve more within economical framework. 

3_Time Management is source of satisfaction and motivation to do more with more self-reliability and confidence. 

4_Time Management is race from start to winning point so whenever time management is part of any work it provides the goals and objectives for becoming a successful player in any field of life. 

5_Time Management is God gifted natural phenomenon and then adopted by humanity. Rotation of whole universe is accruing under time management so as human beings we can manage our time with respect of day and night in different weather and in different locations of the world as per naturally given universal time management. 

6_Time management effects every field of life but the losses cannot be recovered if it is not adopted in agricultural farming as it is nature friendly project. 

7_Time management invents new methodologies to work in short times and also saves money by more productivity in organized time. 

8_There is a famous saying that the time is money how time may be money this is interesting, Any business in this world is to do something for profitability and time is involved in doing something. HERE time management is more important when we consider business with the concept of global village. Every currency is getting change with respect of other currencies because stock exchange is comparing every business using huge internet technologies. 

9_Time management is building the nations across the world because now every country is fighting the economic war and economics is impossible without effective use of time. 

10_Time management is very important in industrial practices because use of labor and machines are working to mold materials in specific given time frame and the cost of working is around 20 to 25 % which is generally equal to profit so if there is no time management there is no profitability. 

11_ Knowledge and education is only possible with effective time management, every school and university has standard time for study programs and teacher, student works together to complete educational programs using time management. 

12_ Time Management is very important during treatment of patients in hospitals and doctors can only treat the patients by time management skills. 

13_ Transportation systems have become very complex because of huge traffics on roads, in airs and in seas and only manageable by using time management techniques. 

Concluding the matter of Time Management I will only say that in recent Era of computers and internet technology time management has become very easier for everyone involved in any field of life, there is only one thing and that is care about the loss of time. 

Do not loose time as it is very precious to win the life, the nations who care about time management has stepped their feet on the moon surface, leading the whole world in technological advancement. 

I am putting the name of Mr Bill Gates who provides the best technologies to entire world to do time management, as per my perception Mr Bill gates is father of time management, whole world should be proud on him. 

How to Avoid Cracks in Buildings

 

Buildings are loaded with different types of loads (Live Loads, Dead Loads, Seismic Loads) which develops stresses in different parts of building and when these stresses exceeds allowable limits then causes cracks.

There are several methods to avoid cracks in buildings.

1- Design and Construction of Foundations.

Design and construction of  foundations is the most important part which can cause cracks in building structure. First of all do soil investigation and find bearing capacity of soil at different depth and layers beneath Ground Level. Adopt  bearing capacity at suitable depth avoiding subsurface water level because water level fluctuation causes extra stresses into foundations.

If sub-surface water level is close to the ground level then provide a Mix of Riverbed Stone and course-sand using equal ratio of by parts and with proper compaction, then provide Plain cement concrete which will provide stiffness while transferring the loads to sub-grade avoiding deformation in sub-grade which can cause uplift of water.

After providing plain cement concrete provide foundation structure which may be brick stepping of Reinforced Cement concrete whatever is feasible ,If adopting brick stepping in foundation than must provide plinth beam with 9 inch width and minimum depth of 6 inches. Size of Plinth beam may be raised according to height and weight of building. To design the size of beam Bending moment may be calculated using 3ft to 5ft as effective span of beam and apply proper loading by area division and wall loads on beams/ foundation.

Remember Do not try to compact  excavated ground level where moisture exceeds 15 % because extra moisture never helps to get required dry density during compaction. At such conditions provide Riverbed Stones and sand mix or provide brick soling under the foundations.

Calculate width of footing comparing to factored loads bearing capacity of soil.

2-In water logged areas provide Columns having basis merged striped RCC (1:2:4) OR RCC (1:1.5:3) footings at Wall corners and mid of walls (If span of rooms exceeds from 18 Ft) jointed with plinth beams (With same width as of columns). Brace all columns at Door/Window Lintel levels and finally brace at roof slab levels.

3- In water logged areas under-ground sub-surface drains may be constructed around the building to keep water level at reasonable distance from foundation of buildings.

4-Wall grooving for piping of water supply ,Gas, Electric Pipes or sewer pipes may also cause the cracking in walls so special care is needed and during fixing of pipes fill the cavities with proper cement concretes then plaster the surface after placing of chicken mesh.

5-Minimum load bearing wall thickness should be 9" inches so do not use smaller walls as load bearing walls as this can also the causes of cracks.

6-Provide Shear Walls in building to minimize lateral stresses caused by lateral loads which can also the main cause of cracks in buildings.

The areas where intensities of earthquakes are higher diagonal beams connecting bottom and tops of columns may be provided to minimize shear loads on walls caused by lateral loads during earthquakes.

7- If load bearing walls are brick walls then do calculation checks to avoid exceed of loadings. Brickwork allowable loading is 50 % of brick bearable loads. So design the walls keeping this check. Construct the walls with properly mixed mortars filling all joints of bricks as per thickness of mortars using brick courses distribution and leveling.

8-Place building paper between slab and wall top to avoid extra stresses caused by contraction and expansion movements of slabs.

9-Adopt proper method for doing of concrete works of RCC and PCC because the main loading material in building works is concrete.

10- Provide RCC concrete pads under the beams if beams are directly resting at load bearing brick or block walls as this may also the cause of crack due to shear load of beam.

11- Fill and compact good class of filling sandy materials under the floors because during settlement floors exerts horizontal pressures on walls which can cause cracks.

11- Do not place electric pipes in concrete covers of RCC Slabs as in most of building hair cracks have been seen on the routes of electric pipes.

12-Walls and Columns should be constructed vertically because it may produce extra stresses in brick work and RCC concretes and also requires extra thick plaster which cracks due to extra  self load of plastering.

13- Provide expansion and contraction joints and reasonable interval and according to produced stresses due to the self load of building parts.

14-Adopt working methodology to avoid any moisture leakage in building structure because of water supply lines ,rain water, and sewer lines.

Building should be fully water tight as it may also be the cause of weaken and cracking the building parts.

15-Design all parts properly and keep good factor of safety for RCC structures and vertical members. Factor of safety may 3 for all parts of buildings.

16- Construction team should be well experienced and professional to execute and supervise the works according to engineering standards.

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Auto level survey calculation

 

Auto level is leveling device consisting on Instrument level machine ,Staff OR Reading Rod, Tripod or Stand. Auto-Level is Used to find out Elevations in different type of surveying processes.

In leveling process some steps are involved to complete survey which are as follows.

1- Establishment of Physical references like Permanent bench marks and Temporary Bench Marks.

2-Measurement and recording of area information as length measurements of features and distance measurement to locate the positions of different features at ground.

3-Calculations of leveling and making different drawings to produce perfect survey report.

I am submitting formulas for leveling work .

 

Height of Instrument  (H.I) = B.S + RL of Bench Mark  OR RL of any Spot.

        Reduced Level  (R.L)  = H.I - B.S OR I.S OR F.S

 

Back Sight                  = B.S     It is first reading after setting of level .

Inter-sight                    = I.S      The readings between B.S and F.S

Fore-Sight                    = F.S    It is last reading before shifting of level machine.

Suppose we have to find out elevations of Ground Floor using leveling process , First of all find any firm reference (As Concrete floors, Foundations) for establishment of Bench Mark. Firstly assuming the value of bench mark as 100 m , and set the level machine near bench mark to take first reading (B.S) and then start other readings (Inter-Sights) at ground where construction work is proposed. At the end survey will be closed with last reading of Fore-Sight (F.S).  The length of Ground where construction has been proposed is 350 Meters. We will enter all readings in leveling table to calculate the Ground Elevations.

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How to Plaster a wall with Cement

 Cement plastering provides smooth and level surface for White wash, Distemper, Weather Shield, or Painting .

Procedure of plastering is very simple but requires techniques to accomplish this technical job .

There are several procedural steps to be adopted in plastering which are as under.

1- Check Alignment and verticalness of wall and mark the difference if it is greater than 1 1/2 ".

2- Fill the dips with rough plastering cement sand mortar (1:2) and rough the surface with wire brush so that good bonding may be produced with plastering layer.

3- If wall contains mounted parts then should be grinded or removed with cutters because if some portions are mounted up to 1 " it means entire wall will require 1.5 " thick plaster in case we are going to do 1/2" thick plaster and that will not be an economical practice. Thicker plastering layers other than nominal thickness causes extra loads which weakens the bonding of plaster with wall and ultimately reduces life of plastering.

4- All grooving for electric or water supply pipes should be completed before starting of plaster and after fixation of conduits in the wall grooving should be filled with rich cement sand mortars having ratios as (1:1) ,(1:2),(1:3)  and after filling activity let it dry for some days and finally cover it with chicken wire mesh .

5- Use corner beads on the mounted corners of walls to get verticalness and straight edges.

6-Fill the joints between slab and wall tops with filler rods and with suitable sealant  materials so that plaster may be done properly.

7-Check diagonals of every wall and make level points using cement sand mortar (1:2) but this level points should also be vertical and should maintain the required plastering thickness.

8-Use Liquid solution having mix of  cement ,sand, water, and 1/8" crush and apply to make the rough surface for good bonding of plastering.

9-Mix the mortar using mixing machine of by manual mixing with suitable cement sand ratios ,normally 1:4 mix is used for outer plastering and (1:5) is used for internal plastering.

10-Before application of cement plaster wall surface must be showered with water to create moisture which will help morter to dry on the wall .

11-Apply cement sand mortar with trowel and spread it with float while pressing and spreading maintain the required thickness of plaster.

12-Depute Good masons and skilled labors for plastering job ,Good mason can do 150 Sq.Ft  OR 14 Sq.m  in eight hours.

13- Curing of plaster should be done for 14 days after application of plastering because cement gains 90 % strength in 14 days.

 

 

 

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