Open Space Requirements For Buildings

Open Space Requirements For Buildings

Open air space for ventilation. Every room intended for human habitation should abut an interior or exterior opening air space of the width r dimensions specified below.

Where height of building above plinth adjoining the open air space does not exceed	Minimum width of open air space throughout
5 m	3.0 m
6 m	3.0 m
9 m	3.9 m
12 m	4.8 m
15 m	5.7 m
18 m	6.6 m
21 m	7.5 m

OPEN SPACE AROUND RESIDENTIAL BUILDINGS

Front open space: every building should have a front yard of minimum width of 3m and in case of two or more sides a width of an average of 3 m but in no case it shall be less than 1.8 m. Such a yard shall form an inseparable part of the site.

Rear open space: Every residential building shall have a yard of an average width of 4.5 m and at no place the yard measuring less than 3 m as an inseparable part of the building, except in the case of back to back sites where the width of the yard could be reduced to 3m provided no erection, re-erection or material alteration of the building shall be undertaken, if at common plot line straight lines drawn downwards and outwards from the line of intersection of the outer surface of any rear wall of the building with the roof perpendicular to that line form an angle of more than 63.5 degree to the horizontal.

Side open space: every residential building may have a permanently open air space not less than 1m in width on one of its sides other than its front and rear and such side open space shall form an inseparable part of the site. In case, side open air space is to be used for ventilation, it shall be in accordance with the requirements mentioned in the previous paragraph. In case, the side open space abuts a road, the width shall not be less than 3m.

OPEN SPACE FOR BUILDINGS OTHER THAN RESIDENTIAL

The front, rear and side yards, widths and the rules governing those shall be laid down by the authority in each case.

The rules applicable to residential buildings with regard to front open space, rear open space and the side open space and the angle 45 and 63.5 degree governing erection, re-erection or material alteration of a residential building sall also be applicable to business and industrial buildings, provided, however that the local authority may prescribe the front and rear open spaces as required.

Methods of Estimation In Building Works

Methods of Estimation In Building Works

The estimation of building quantities like earth work, foundation concrete, brickwork in plinth and super structure etc., can be workout by any of following two methods:

a) Long wall – short wall method

b) Centre line method.

c) Partly centre line and short wall method.

A) LONG WALL-SHORT WALL METHOD:

In this method, the wall along the length of room is considered to be long wall while the wall perpendicular to long wall is said to be short wall. To get the length of long wall or short wall, calculate first the centre line lengths of individual walls. Then the length of long wall, (out to out) may be calculated after adding half breadth at each end to its centre line length. Thus the length of short wall measured into in and may be found by deducting half breadth from its centre line length at each end. The length of long wall usually decreases from earth work to brick work in super structure while the short wall increases. These lengths are multiplied by breadth and depth to get quantities.

B) CENTRE LINE METHOD:

This method is suitable for walls of similar cross sections. Here the total centre line length is multiplied by breadth and depth of respective item to get the total quantity at a time. When cross walls or partitions or verandah walls join with main wall, the centre line length gets reduced by half of breadth for each junction. Such junction or joints are studied carefully while calculating total centre line length. The estimates prepared by this method are most accurate and quick.

C) PARTLY CENTRE LINE AND PARTLY CROSS WALL METHOD:

This method is adopted when external (i.e., around the building) wall is of one thickness and the internal walls having different thicknesses. In such cases, centre line method is applied to external walls and long wall-short wall method is used to internal walls. This method suits for different thicknesses walls and different level of foundations. Because of this reason, all Engineering departments are practicing this method.

Size and Quantity of Reinforcement Required For Building Works

Size and Quantity of Reinforcement Rebar Required For Building and Other Commercial Works

Reinforcement is required for reinforced concrete members such as footings, beams, columns, slabs, lintels etc. Estimation of reinforcement quantity is required prior to tendering stage to calculate approximate cost of project or construction work.

Following table gives the estimated quantities of reinforcement and its size generally used for various building works:

Sl. No	RCC Member	Quantity in kg/m3	Size of reinforcement required
1	Column footings	75	10mm  or 12mm
2	Grade beams	100	12mm, 16mm – 85%
			Stirrups – 6mm or 8mm– 15%
3	Plinth beams	125	8mm diameter – 85%,
			Stirrups 6mm – 15%
4	Columns	225	16mm, 20mm and 25mm – 90%
			Ties – 6mm or 8mm – 10%
5	Lintel beam	125	12mm, 16mm dia – 85%
			Stirrups – 6 mm or 8mm – 15%
6	Sunshades	60	8mm dia – 75%
			Distributer – 6mm – 25%
7	Canopy slab upto 2.0 m span	125	10mm dia – 80%
			Distributor bars – 6mm or 8mm – 20%
8	Staircase waist slab	150	12 or 16mm dia – 80%
			Distributor 8mm dia – 15%
9	Roof slab
	(a)  One way slab	80	8mm dia – 70%
			Distributor – 6mm – 30%
	(b)  Two way slab	100	8mm dia – 100%
	(c)  Square slab – 4m to 6m size	150	10 – 12mm dia – 100%
10	Main beams above 6m	250	20mm, 16mm, 12mm – 80 – 85%
			Stirrups – 8mm – 15 – 20%

All above mentioned steel are round tapered steel. This data is just for estimation of quantity of steel for various RCC works. This does not provide actual steel required for all the members. Actual quantity of steel required can be calculated from the drawings prepared after structural design. 

Units Of Measurement and Payment for Various Items

Units of measurement and payment for various items

Sl. No.	Particulars of items	Units of measurement	Unit of payment
1	Earthwork: Excavation, filling, cutting, banking	m3	m3
2	Surface dressing	m2	m2
3	Cutting of trees	Number	Per number
4	Stones: quarrying, blasting	m3	m3
5	Concrete : PCC, RCC, Precast	m3	m3
6	Jail works	m2	m2
7	Damp proof course	m2	m2
8	Brick work of any description	m3	m3
9	Thin partition wall	m2	m2
10	String course, drip course, water course coping etc	m	m
11	Stone work of any description	m3	m3
12	Stone work in wall facing (thickness specified)	m2	m2
13	Wood work: truss, rafter, beam etc	m3	m3
14	Door, window shutters	m2	m2
15	Door, window fittings	Number	Per number
16	Timbering, boarding, sawing of timber, timbering of trenches, partition, etc	m2	m2
17	Steel work	Quintal	Per quintal
18	Expanded metal, fabric reinforcement, cutting angles, plates, tees	cm2	cm2
19	Threading; welding; solder of sheets	cm	Per cm
20	Iron gate, grill collapsible gate, rolling shutter	m2	m2
21	Iron railing	m	m
22	Roofing: tiled, corrugated iron, caves board (thickness specified)	m2	m2
23	Centering, shuttering	m2	m2
24	Ridges; valleys; gutters (girth given)	m	m
25	Expansion and contraction joints	m	m
26	Ceiling timber, A.C. sheet, board, etc	m2	m2
27	Plastering; pointing; white washing; distempering; painting; varnishing; polishing; coal tarring; removing of paints	m2	m2
28	Flooring of any kind	m2	m2
29	Pipes, laying of pipes	m	m
30	Dismantling of brick masonry	m3	m3
31	Grouting	m2	m2
32	Grouting of cracks, joints	m	m
33	Supply of sand; brick ballast; aggregates; timber	m3	m3
34	Supply of cement	Bag	Per bag
35	Supply of steel, G.I. sheet, bare electric line	Quintal	Per quintal
36	Supply of GI sheet	m2	m2
37	Supply of sanitary items	Number	Per number
38	Supply of paint, varnishes	Litre	Per litre
39	Supply of explosives, stiff paint	Kg	Per kg

Methods And Units Of Measurements Of Civil Works

The units of measurements (UOM) for civil engineering works are mainly categorised for their nature, shape and size and for making payments to the contractor and also. The principle of units of measurements normally consists the following:

Units of measurement

a) Single units work like doors, windows, trusses etc., are expressed in numbers.

b) Works consists linear measurements involve length like cornice, fencing, hand rail, bands of specified width etc., are expressed in running metres (RM)

c) Works consists areal surface measurements involve area like plastering, white washing, partitions of specified thickness etc., and are expressed in square meters (m2)

d) Works consists cubical contents which involve volume like earth work, cement concrete, Masonry etc are expressed in Cubic metres.

Table below shows units of measurement of various items of civil engineering works based on IS 1200.

Sl. No.	Particulars of item	Units of measurement	Units of payment
1	Earthwork
	1.       Earthwork in excavation	CUM	Per CUM
	2.       Earthwork in filling in foundation trenches	CUM	Per CUM
	3.       Earth work in filling in plinth	CUM	Per CUM
2	Concrete
	1.       Lime concrete in foundation
	2.       Cement concrete in lintels
	3.       RCC in slab
	4.       Cement concrete or RCC in chujja, sunshade
	5.       Lean concrete in roof terracing (thickness specified)	SQM	Per SQM
	6.       Cement concrete bed	CUM	Per CUM
	7.       Reinforced concrete sunshade (specified width and height)	CUM	Per CUM
3	Damp proof course (DPC) – thickness mentioned	SQM	Per SQM
4	Brick work
	1.       Brickwork in foundation	CUM	Per CUM
	2.       Brickwork in plinth
	3.       Brickwork in super structure
	4.       Thin partition walls	SQM	Per SQM
	5.       Brickwork in arches	CUM	Per SQM
	6.       Reinforced brickwork	CUM	Per CUM
5	Stone work
	1.       Stone masonry	CUM	Per CUM
6	Wood work
	1.       Doors and windows frames or chaukhats, rafters, beams	CUM	Per CUM
	2.       Shutters of doors and windows (thickness specified)	SQM	Per SQM
	3.       Doors and windows fittings (like hinges, tower bolts, sliding bolts, handles)	Earch	Per Each
7	Steel work
	1.       Steel reinforcement bars etc in RCC and reinforced brick work	Quintal	Per Quintal
	2.       Bending, binding of steel reinforcement	Quintal	Per quintal
	3.       Rivets, bolts and nuts, anchor bolts, lewis bolts, holding down bolts	Quintal	Per quintal
	4.       Iron hold fasts
	5.       Iron railing (height and types specified)
	6.       Iron grills	SQM	Per SQM
8	Roofing
	1.       RCC and RB slab roof (excluding steel)	CUM	Per CUM
	2.       Lean concrete roof over and inclusive of tiles or brick or stone slab etc (thickness specified)	SQM	Per SQM
	3.       Centering and shuttering formwork	SQM	Per SQM
	4.       AC sheet roofing	SQM	Per SQM
9	Plastering, points and finishing
	1.       Plastering – cement or lime mortar (thickness and proportion specified)	SQM	Per SQM
	2.       Pointing	SQM	Per SQM
	3.       White washing, colour washing, cement washing, (number of coats specified)	SQM	Per SQM
	4.       Distempering (number of coats specified)	SQM	Per SQM
	5.       Painting, varnishing (number of coats specified)	SQM	Per SQM
10	Flooring
	1.       25mm cement concrete over 75mm lime concrete floor (including lean concrete)	SQM	Per SQM
	2.       25mm or 40mm cement concrete floor	SQM	Per SQM
	3.       Doors and window sills (CC or cement mortar plain)	SQM	Per SQM
11	Rain water pipe / plain pipe	RM	Per RM
12	Steel wooden truss	Each	Per each
13	Glass panels (supply)	SQM	Per SQM
14	Fixing of glass panels or cleaning	Each	Per Each

Note:

SQM = Square meter

CUM = Cubic meter

RM = Running meter

METHODS FOR MEASUREMENT OF CIVIL ENGINEERING WORKS:

The rules for measurement of each item are invariably described in IS – 1200. However some of the general rules are listed below:

1. Measurement shall be made for finished item of work and description of each item shall include materials, transport, labour, fabrication tools and plant and all types of overheads for finished the work in required shape, size and specification.

2. In booking, the order shall be in sequence of length, breadth and height or thickness.

3. All works shall be measured subject to the following tolerances.

• Linear measurement shall be measured to the nearest 0.01m.
• Areas shall be measured to the nearest 0.01 SQM
• Cubic contents shall be worked out to the nearest 0.01 cum.

4. Same type of work under different conditions and nature shall be measured separately under separate items.

5. The bill of quantities shall fully describe the materials, proportions, workmanships and accurately represent the work to be executed.

6. In case of masonry (stone or brick) or structural concrete, the categories shall be measured separately and the heights shall be described as:

• From foundation to plinth level
• From plinth to first floor level
• From first floor to second floor level and so on.