Construction Activities with units
(Engr. Ubaid Ahmad Mughal)
Construction Activities with units, Earth work:-
Earth work in excavation and earth work in back filling are usually taken out separately under different items, and quantities are calculated in cum. Foundation trenches (Trenches are generally defined by being deeper than they are wide and by being narrow compared to their length) are usually dug to exact width of foundation with vertical sides. Earth work in excavation in foundation is calculated by taking the dimension of each trench length × breath × depth. (Breath: distance from side to side). Filling in trenches after construction of foundations masonry is ordinary neglected. If the trench filling is accounted, this may be calculated by deducing the masonry from the excavation.
Extra earth if required for filling is brought from outside. If there is surplus earth after trench and plinth filling, this may be utilized in leveling and dressing of suite or carted away and removed.
Construction Activities with units, Concrete in foundation:-
The concrete is taken out in cum by length × breath × thickness. The length and breadth of foundation concrete are usually the same as for excavation, only the depth and thickness differ. The thickness of concrete varies from 20cm to 45cm, usually 30cm (9” to 18” usually 12”). Foundation concrete consists of lean concrete or weak cement concrete. The proportion of cement concrete in foundation may be 1:4: 8 or 1:5: 10. ( What is Concrete ? Click here to Learn )
Construction Activities with units, Soling:-
When the soil is soft or bad, one layer of dry brick or stone is applied below the foundation concrete. The soling layer is computed in sq m (length × breath) specifying the thickness
Construction Activities with units, Damp proof course:-
D.P.C is usually 205cm (1”) thick rich cement concrete 1: 11/2 : 3 or 2cm,( ¾”) thick rich cement mortar 1 : 2, mixed with slandered waterproofing material, is provided at the plinth level to full width of plinth wall, and the quantities are computed in sq m, (length × breath). Usually D.P.C is not provided at the sill of the doors and veranda opening, for which deductions are made, (One kg of Cem- seal or Impermo or the other standard waterproofing compound per bag of cement is generally used).
Construction Activities with units, Masonry:-
Masonry is computed in cu m (length × breath × Height). Foundation and plinth masonry are taken under one item, and masonry in superstructure is taken under a separate item. In storied building the masonry in each storey as ground floor above plinth level, first floor, etc is computed separately. in taking out quantities wall are measured as solid and then deduction are made for openings as doors , windows, etc. masonry with different types and classes, masonry with different mortars etc. are taken out under separate items. Splayed or rounded sides of wall are considered as rectangular and extreme dimensions are taken to find out the quantities. Thin partition wall is measured in sq m. honey comb brick wall is taken under separate item in sq m; no deduction is made for holes. Stone masonry is calculated in the same manner as for the brick masonry. ( Bricks and Classification can be seen here )
Construction Activities with units, R.C.C and R.B.C work:-
R.C.C (Reinforced Cement Concrete) and R.B.C (Reinforced Brick Concrete) work may be in roof or floor slab, in beams, lintel, columns, foundations, etc. and the quantities are calculated in cu m exclusive of the steel reinforcement and its bending but inclusive of centering and shuttering and fixing and binding reinforcement on position. 0.6% to 1 %( usually 1%) of R.C.C or R.B work by volume may be taken for steel.
Centering and shuttering (form work) are usually considered as R.C.C and R.B work, but may also be taken as separately in sq m of surface in content with concrete. ( Cost Comparison of R.C.C and R.B.C of 1 Kanal House )
Construction Activities with units, Flooring and roofing:-
Ground Floor:-
The base lime concrete and floor finishing of C.C or stone or marble or mosaic, etc are usually taken as one job or one item and quantities are taken in sq m multiply the length by the breath. The length and breadth are taken as inside dimensions from wall to wall of superstructure.
1st floor, 2nd floor, etc:-
Supporting structure is taken separately in cu m as R.C.C or R.B, etc. and floor finishing is taken as separately in sq m as 2.5cm or 4cm(1” or 11/2”) C.C or marble or mosaic,etc.
Roof:-
Supporting structure is taken separately in cu m and the lime concrete terracing is computed in sq m with thickness specified, under a separate item including surface rendering smooth.
Construction Activities with units, Plastering and Pointing
Plastering usually 12mm(1/2”) thick is calculated in sq m. for wall the measurements are taken for the whole face of the wall for the both sides as solid, and deduction for opening are made as following manners:-
- No deduction is made for ends of beam, posts, rafters, etc.
- For small opening up to 0.5 sq m (5 sq ft) no deduction is made and at the same time no addition is made for jambs, soffits and of sills of these openings.
- For opening exceeding from 0.5 sq m (5 sq ft) but not from 3 sq m (30 sq ft) the deduction is made only for one face.
- For opening greater the 3 sq m (30 sq ft) deduction is made for the both faces of the opening and the jambs, soffits and sills are taken into account and added.
Pointing in wall is calculated in sq m for whole surface and deductions similar to plastering are made. ( Learn about Plastering and Pointing Here )
Construction Activities with units, Pillars:-
Pillars are taken separately in cum for their net volume and quantities are calculated by correct geometrical measurements by simple method. Hexagonal, octagonal, etc pillars are dealt similarly.
Plastering in the pillars are calculated in sq m by multiplying the circumference of the perimeter by the height.
Construction Activities with units, Door and windows:-
Chowkhat and Frame:-
Door and window frames or chowkhats are computed in cu m. length is obtained by adding the length of all the members of the chowkhat, top and two verticals if there is no sill member, and adding bottom also.
Door or window leaves or Shutters:-
They are computed in sq m by multi plying the breath by height of shutters, the rebates in the chowkhat should be taken into consideration in finding the breath and the height.
Construction Activities with units, Wood work:-
Wooden beams, burgahs, posts, wooden roof trusses, chowkhats, etc. come under this item, and quantities are computed in cu m. The dimensions of the finished work shall be taken.
Construction Activities with units, Iron Work:-
This is computed in weight in kg or quintal and quantities are calculated correctly by multiplying weights per running meter by the length. The weight of bolts, nuts and rivets with heads can be calculated by counting their numbers and sizes and consulting steel table. Sometimes certain percentage is provided for the bolts, nuts and rivets, etc.
Construction Activities with units, White-washing or colour-washing or Distempering:-
The quantities are computed in sq m and are usually same as for the plastering. Deduction is dealt in the same manners as for the plastering.
Construction Activities with units, Painting:-
Painting or varnishing of doors and windows are computed in sq m, the dimension should be taken for the outer dimension of chowkhat. The area is measured flat. Painting is done in two or three coats, usually over a coat of priming. The rates cover for the number of coats under one item.
Construction Activities with units, Other items:-
For other items the unit of different works may be consulted. The units being know it will not be difficult to estimate the quantities of different item of work.
Summary of Construction Activities with units
( Learn more about Construction Materials here )
Construction Activities with units, Construction Activities with units, Construction Activities with units, Construction Activities with units, Construction Activities with units, Construction Activities with units, Construction Activities with units, Construction Activities with units, Construction Activities with units, Construction Activities with units, Construction Activities with units, Construction Activities with units, Construction Activities with units, Construction Activities with units, Construction Activities with units, Construction Activities with units, Construction Activities with units, Construction Activities with units, Construction Activities with units