How a house is built

Every part of a typical Indian house, from the soil up, in the order it is built: what each part is, why it is there, its usual size and what it is made of.

Sizes here are typical, not a design. They show what is common in small Indian homes (ground or G+1, RCC frame, brick walls) so that you can read drawings and talk to builders. The real sizes of footings, columns, beams, slabs and their steel come from a structural engineer who has seen your soil test and loads. Setbacks, heights and coverage come from your local building bylaws.

Most new houses in India are RCC framed: a skeleton of reinforced-concrete footings, columns, beams and slabs carries the weight down to the soil, and brick or block walls simply fill the gaps between the columns. Older and very small houses are often load-bearing: thick walls carry the roof themselves and sit on a continuous strip footing. This page follows the framed house, and points out where load-bearing work differs.

Compound wall and gate
Paving and car parking
Sump (underground tank)
Footing on a PCC bed
Neck column
Plinth beam with DPC
Plinth filling and floor
Column (pillar)
Brick wall
Door, under its lintel
Window, lintel and chajja
Roof beam and slab
Terrace waterproofing
Parapet
Overhead tank
Drain and inspection chamber
Septic tank and soak pit

A house cut open from the front gate (left) to the back wall (right). Each part has its own section below.

The parts of an RCC framed house, cut through one bay. Levels in mm from the natural ground. Load flows down: slab → beam → column → footing → soil.

The order of work

A typical sequence for a single-storey house of about 1000 sq ft: roughly 8 months. Each extra floor adds about 2–3 months. Bars overlap where crews can work in parallel. Weather, approvals and money flow change this a lot.

Paperwork and soil. Survey, soil test, architect's plan, structural design, building permit.
Site. Clear and level the plot, set up water and power for construction, mark the column and wall positions.
Foundation. Dig pits, lay PCC, cast footings and neck columns, anti-termite treatment, backfill.
Plinth. Plinth beams, plinth filling, DPC. The house now has its floor level.
Ground-floor frame and walls. Columns up to lintel level, brickwork with door and window frames, lintels and sunshades, brickwork up to beam level.
Roof. Centering, beam and slab steel, conduits in the slab, concreting, curing.
Upper floors. Repeat steps 5 and 6, then the staircase headroom, parapet and water-tank platform.
Rough services. Electrical conduits and plumbing pipes cut into walls before plastering.
Plastering and waterproofing. Inside and outside plaster, bathroom and terrace waterproofing.
Finishes. Flooring and wall tiles, door shutters, windows, putty and paint, electrical and sanitary fittings.
Outdoor. Sump, septic tank or sewer connection, compound wall, gates, paving.

1Site and soil

The plot and setbacks

What: The land you build on, and the open margins (setbacks) you must leave between the house and each boundary.
Why: Bylaws require setbacks for light, air, fire access and privacy. They also limit ground coverage (how much of the plot the house may cover) and FAR/FSI (total floor area ÷ plot area).
Typical: Front 3 m (10') or more; sides and rear 1–1.5 m (3'–5') for small plots. Rules differ a lot between cities and panchayats: check yours.

Plots are quoted in feet. A 30' × 65' plot is 9.14 m × 19.81 m = 1950 sq ft (181 m²). A plot is north facing when the road is on its north side, so the main gate and usually the main door face north.

A north-facing 30' × 65' plot. With these example setbacks the footprint is about 24' × 50' (1200 sq ft) per floor.

Soil test

What: A geotechnical investigation: trial pits or boreholes, usually 2–3 for a house, with lab tests of the soil.
Why: It gives the safe bearing capacity (SBC): how much load each square metre of soil can carry, and at what depth. The engineer sizes the footings from it. It also reveals filled-up soil, black cotton (expansive) soil, rock and the water table.
Typical: SBC of 100–200 kN/m² (10–20 t/m²) for ordinary firm soil at 1.5 m depth; black cotton soil and loose fill are much weaker and need special footings.

Site clearing

Remove plants, roots, debris and the loose topsoil (about 150 mm, 6"), fill pits and level the plot. Arrange a construction water source (borewell or tanker plus a temporary sump), a temporary electricity connection, and space to store cement out of the rain, stack bricks and sand, and bend steel.

Marking out

What: Transferring the drawing onto the ground: a centre-line drawing gives the centre of every column and wall from fixed reference lines.
How: Fix a base line parallel to the road, set out right angles with the 3-4-5 rule (3 m, 4 m, 5 m sides) or a total station, check diagonals, and mark pit outlines with lime powder. Strings stretched between profile boards or pegs placed outside the digging area keep the centre lines after the soil is dug away.
Check: Diagonals of every rectangle should match within a few mm. Mistakes here are built into everything after.

2Foundation

The foundation is everything below the floor level: it spreads the weight of the house onto soil that can carry it. In a framed house each column stands on its own footing; in a load-bearing house each wall stands on a continuous strip.

An isolated (pad) footing. The pit is dug 300 mm wider than the PCC on every side so masons can work; after the footing and neck are cast, it is backfilled with soil.

Excavation and pits

What: Digging a pit at each column position (or a trench under each load-bearing wall) down to firm soil.
Why: Topsoil is soft and moves with moisture. Going down reaches soil that is stronger and stable.
Typical: 1.2–2 m deep (4'–6½'), as set by the soil test; 1.5 m (5') is common. Pit size = PCC size + 300 mm (1') working space each side: for a 1500 mm PCC bed, a 2100 × 2100 mm (7' × 7') pit.
Watch: Level and ram the pit bottom. Shore deep pits in loose soil, pump out water, and never cast a footing on fill or mud.

PCC bed

What: Plain cement concrete (no steel), a thin lean layer at the bottom of the pit.
Why: A clean, level, hard base on which to place the footing steel and its cover blocks; it stops the footing's cement slurry soaking into the soil.
Typical: 100 mm (4") thick (75–150), projecting 150 mm (6") beyond the footing on every side. Mix 1:4:8 (M7.5) or 1:3:6 (M10).

Isolated (pad) footings

What: A square or rectangular slab of reinforced concrete under each column. It can be flat or sloped (thicker at the centre).
Why: A column carries tonnes on a small area; the pad spreads that load over enough soil that the soil's bearing capacity is not exceeded.
Typical: 1200 × 1200 × 300 mm (4' × 4' × 1') for a G+1 house on firm soil; 900–1800 mm square depending on load and soil. Concrete M20. A mesh of 10–12 mm TMT bars at 150 mm (6") spacing both ways, bent up at the ends, with 50 mm cover.
Steel: Column bars are tied into the footing mesh with an L bend, so the column is continuous from the footing up.

When two columns are so close that their pads would overlap, they share a combined footing. On very weak soil the whole house may sit on a raft (one large slab) or on piles. These are the engineer's call.

Strip footings for load-bearing walls

What: A continuous foundation under a wall: stepped brick or stone masonry on a PCC bed, or an RCC strip.
Why: A load-bearing wall carries load along its whole length, so the foundation must too. Compound walls and some outhouses use them even in framed houses.
Typical: PCC 1:4:8, about 150 mm thick and 2–3 times the wall width; brick footing steps out 57 mm (2¼") each side every 2 courses; 0.9–1.2 m (3'–4') deep. Stone (size-stone or random rubble) is common where it is local.

A strip footing: the wall widens in steps until its load is spread over a wide enough strip of soil.

Column below plinth (neck column)

What: The part of the column from the top of the footing up to the plinth beam; also called the pedestal or stub column.
Why: It carries the column load through the backfilled pit down to the footing.
Typical: The same size and bars as the column above (for example 230 × 300 mm), about 1.2–1.5 m tall. The pit is backfilled around it once the concrete has cured.

Plinth beam

What: An RCC beam linking the columns at plinth level, along every wall line.
Why: It carries the ground-floor walls, ties the columns together so they do not move apart, and resists uneven settlement of the soil. It also makes a level, crack-free base for the walls.
Typical: 230 × 300 mm (9" × 1'), top at plinth level, which is 450 mm (1'6") above the ground (300–600 mm; higher on low or flood-prone land). Usually 4 bars of 12 mm with 8 mm stirrups at 150 mm.

In OctBuild the foundation uses these same defaults: a 1200 × 1200 × 300 mm pad on a 100 mm PCC bed projecting 150 mm, founded 1.5 m below ground, in a pit 300 mm wider than the bed each side, and a 230 × 300 mm plinth beam at a 450 mm plinth.

Plinth filling

What: Filling the space inside the plinth beams, up to just below floor level.
Why: It raises the floor above the ground and makes a firm base for the floor; badly compacted fill is the usual cause of sunken, cracked floors.
How: Good soil, murrum or sand in 150–200 mm (6"–8") layers, each watered and rammed or plate-compacted. Then a 75–100 mm (3"–4") PCC bed (1:4:8) on top, and the floor finish on that.

DPC (damp-proof course)

What: A waterproof layer across the full width of every wall at plinth level, on top of the plinth beam.
Why: Brick soaks up ground moisture like a wick. Without a DPC, damp climbs the walls, peels the paint and grows salts.
Typical: 40–50 mm (1½"–2") of 1:1.5:3 cement concrete with a waterproofing compound, often finished with a bitumen coat. It must not be broken by the plaster below.

Anti-termite treatment

What: A chemical barrier in the soil around and under the house (as per IS 6313), applied by a licensed pest-control agency.
Why: Termites travel through soil and attack doors, frames, cupboards and wiring. Treating the soil before the floor is laid is far cheaper than treating a finished house.
When: On the bottom and sides of pits and trenches, on the backfill around the foundation, on each layer of plinth filling, and along the outer face of the plinth.

3Superstructure: the frame

Everything above the plinth is the superstructure. Its RCC frame is cast in place: carpenters build formwork (shuttering for sides, centering under slabs), bar-benders tie the steel, the concrete is poured and vibrated, and then it is cured (kept wet) for 7–14 days.

Columns (pillars)

What: Vertical RCC members at wall corners and junctions, rising from the footing to the roof.
Why: They carry the beams and slabs, and everything on them, down to the footings.
Typical: 230 × 230 mm (9" × 9") minimum; 230 × 300 or 230 × 450 mm (9" × 12" or 9" × 18") are common for G+1. Usually 3–4.5 m (10'–15') apart. At least 4 bars of 12 mm (often 6 bars of 12–16 mm), with 8 mm ties at 150 mm, 40 mm cover. M20 concrete.
Tip: Make columns as wide as the wall (230 mm) so they hide inside it.

Beams

What: Horizontal RCC members between columns, at each floor and roof level, usually cast together with the slab.
Why: They collect the load of the slab and the walls above, and pass it to the columns.
Typical: 230 mm wide; depth roughly span ÷ 12, including the slab: 300–450 mm (12"–18") for 3–4.5 m spans. Bottom and top bars of 12–16 mm, 8 mm stirrups closer near the columns, 25 mm cover.

Slabs (floor and roof)

What: The flat RCC plate that forms the floor of the upper storey or the roof.
Why: It carries people, furniture, water tanks and finishes, and spans between the beams.
Typical: 125–150 mm (5"–6") thick for spans up to about 4.5 m. A mesh of 8–10 mm bars at 150–200 mm, 15–20 mm cover. A two-way slab (roughly square panel) carries load in both directions; a one-way slab (long, narrow panel) mostly across the short side.
Watch: Place electrical conduits, fan boxes and plumbing sleeves before pouring. Keep the props in place for 7–14 days or more (longer for longer spans), and cure the slab with ponded water.

Lintels and sunshades (chajjas)

What: A lintel is a small RCC beam over a door or window opening. A sunshade or chajja is a thin slab projecting out from the lintel over a window.
Why: The lintel carries the brickwork above the opening. The chajja keeps rain and summer sun off the window.
Typical: Lintel as wide as the wall, 150 mm (6") deep, resting 150–200 mm on the wall each side, top of opening at 2100 mm (7'). Often all lintels are cast as one continuous lintel band round the house, which also helps resist earthquakes. Chajja 450–600 mm (1'6"–2') projection, 75–100 mm thick, tapering outward.

Staircases

What: An RCC slab (the waist slab) with steps cast on top, rising between floors. Common shapes: straight, L-shaped, and dog-legged (U-shaped, two flights with a landing).
Typical: Riser 150–175 mm (6"–7"), tread 250–300 mm (10"–12"), width at least 900–1000 mm (3'–3'4"). About 18–20 risers for a 3 m (10') floor height. Waist slab 125–150 mm. Clear headroom at least 2100 mm (7'). Handrail about 900 mm (3') high.
Rule: A comfortable step follows 2 × riser + tread ≈ 600–630 mm.

One stair flight. Every riser in a flight must be the same height, or people trip.

4Walls

Brick and block masonry

What: Walls built of burnt clay bricks, or of blocks: solid concrete blocks, AAC (light, aerated) blocks, fly-ash bricks, or laterite stone in Kerala and Konkan.
Why: In a framed house the walls enclose rooms, keep out weather and noise, and carry their own weight only; in a load-bearing house they carry the roof too.
Sizes: Traditional brick about 230 × 110 × 75 mm (9" × 4½" × 3"); modular brick 190 × 90 × 90 mm. AAC block 600 × 200 mm face, 100–200 mm thick.
Good work: Soak clay bricks before laying; keep joints about 10 mm and fully filled; break joints between courses (no vertical joint above another); raise no more than about 1 m (3') a day; leave toothing where a wall will continue later; cure for 7 days.

230 mm vs 115 mm walls

Seen from above. Real 230 mm walls alternate courses of bricks laid across (headers) and along (stretchers), as in English bond, so the wall is tied through its thickness.

Wall	Used for	Mortar	Notes
230 mm (9")	Outer walls, walls between houses, walls carrying loads	1:6	Better for heat, security and sound. About 260 mm finished with plaster both sides.
115 mm (4½")	Inner partitions between rooms, bathroom walls	1:4	Needs a reinforcement band or bars every few courses; cannot carry slabs. About 140 mm with plaster.

Mortar

What: A paste of cement, sand and water that beds and bonds the bricks.
Mixes: By volume, cement : sand. 1:6 for 230 mm brickwork, 1:4 for 115 mm walls, 1:4 to 1:6 for plaster. Ready-mixed thin-bed adhesive is used for AAC blocks.
Watch: Mix only what can be used within about 30 minutes; do not re-temper mortar that has started to set.

5Openings: doors, windows, ventilators

Openings line up at lintel level, 2100 mm (7') above the finished floor, so one lintel band can run over all of them. Levels here are from the finished floor.

Doors

Typical: Main door 1050–1200 × 2100 mm (3'6"–4' × 7'); rooms 900 × 2100 mm (3' × 7'); bathrooms 750 × 2100 mm (2'6" × 7'). Sizes are of the opening including the frame.
Shutters: Teak or other hardwood panelled for the main door; flush doors (plywood-faced) for rooms; PVC, WPC or FRP for bathrooms, which do not swell with water.

Windows and ventilators

Windows: 1200–1500 mm (4'–5') wide, 1200 mm (4') high, sill 900 mm (3') above the floor. Window area should be at least about one-tenth of the floor area for daylight. Wood, steel, aluminium or uPVC, with glass shutters and usually a steel grill for security.
Ventilators: Small high openings, about 600 × 450 mm (2' × 1'6") with the sill at 1650 mm, for bathrooms, toilets and stores. Often louvred glass, with an exhaust fan opening.

Frames

What: The fixed outer frame (chaukhat) into which the shutters are hung.
When: Fixed while the wall is built: the door frame stands on the floor level before brickwork starts beside it; window frames are set when the wall reaches sill height. Steel holdfasts on the frame are bedded in the brickwork joints.
Materials: Hardwood (teak, sal, honne), steel (pressed sheet), precast concrete, or uPVC/aluminium sections. Treat wooden frames with anti-termite primer on the faces that touch the wall.

6Finishes

Plastering

What: A coat of cement-sand mortar over the brickwork and concrete.
Why: It gives a smooth, true surface for paint, closes gaps and protects the walls from rain.
Typical: Inside walls 12 mm (½"), 1:6. Outside walls 20 mm (¾") in two coats, 1:4, often with a waterproofing additive. Ceilings 6–10 mm, 1:3 or 1:4. Gypsum plaster is a smooth, faster alternative inside.
Watch: Fix chicken mesh where brick meets concrete (these joints crack), finish all conduit and pipe chases first, and cure outside plaster for 7 days.

Flooring and tiling

Flooring: Vitrified tiles (600 × 600 or 800 × 800 mm, 2' × 2' or 2'8" × 2'8") are the most common; granite, marble, Kota stone, Athangudi and red-oxide floors are alternatives. Laid on a cement mortar bed (1:4) or tile adhesive on the PCC sub-floor; 40–50 mm total from the slab or PCC to the finished floor.
Wall tiles: Bathrooms tiled to 2100 mm (7') or full height; kitchens have a dado about 600 mm (2') high above the counter. A skirting strip 100 mm (4") high along the foot of all walls protects them from mops.
Slopes: Bathroom floors slope 1:60 to 1:100 towards the floor trap; balconies slope away from the door.

Floors and roofs are built up in layers; each one has a job. Thicknesses are exaggerated for the thin layers.

Painting

Inside: 1–2 coats of wall putty to fill and smooth, a coat of primer, then 2 coats of emulsion (or cheaper distemper).
Outside: Primer and 2 coats of exterior (weather-proof) emulsion; texture paints hide hairline cracks.
Wood and metal: Enamel paint, PU or melamine polish on wood; red-oxide primer and enamel on steel grills and gates.

Waterproofing

Why: Leaks and damp are the most common and most expensive defects in Indian houses. Water gets in at the terrace, bathrooms, sunken slabs, window edges, and wherever pipes pass through.
Terrace: A waterproofing coat or membrane on the slab, then brickbat coba (broken brick in lime or cement mortar) laid to a slope of about 1:100 towards rain-water outlets, finished with tiles. The coating turns up the parapet about 300 mm.
Bathrooms: A waterproofing coat on the floor and 300 mm up the walls (higher in the shower) before tiling, with the floor trap sealed into it. Test by flooding with water for 24–48 hours before tiling.

7Services

Water comes in to the sump, is pumped up to the overhead tank, and flows down by gravity to the taps. Waste water runs out through inspection chambers to the sewer, or to a septic tank and soak pit where there is no sewer.

Plumbing (water supply)

What: Pipes from the overhead tank to every tap, shower, WC cistern, washing machine and geyser.
Materials: CPVC for hot and cold water inside walls; uPVC or HDPE for outside and the rising main; GI is now rarely used. Typical sizes 15–25 mm (½"–1").
Watch: Pressure-test all concealed pipes before plastering or tiling over them. Note where they run, so nobody drills into them later.

Drainage

What: Pipes carrying used water away: soil pipes from WCs and waste pipes from basins, showers and the kitchen, plus rain-water pipes from the terrace.
Typical: PVC SWR pipes: 110 mm (4") for WCs, 75 mm (3") for waste, 75–110 mm for rain water. Outside, pipes slope 1:40 to 1:60 to inspection chambers (about 450 × 450 mm) at every junction and change of direction. Gully traps and floor traps hold water to keep smells out.

Electrical

What: The meter, a distribution board (DB) with MCBs and an RCCB (earth-leakage breaker), and wiring in PVC conduits to every switch, socket and light.
Typical: Copper wire 1.5 mm² for lights and fans, 2.5 mm² for 6 A/16 A sockets, 4 mm² for ACs and geysers. Switch boards about 1200 mm (4') above the floor. At least one earth pit, two for safety.
When: Conduits for ceiling lights and fans go in the slab before concreting; wall conduits are cut in after brickwork and before plastering. Plan furniture first, so sockets land in the right place.

Septic tank or sewer

Sewer: Where the city has an underground drainage line, the house drain joins it through a final inspection chamber at the boundary (with permission from the local body).
Septic tank: Where there is no sewer: an underground watertight tank, often in two chambers, where solids settle and digest. The liquid goes to a soak pit or drain field. Sized for the number of users (about 1.5 × 1 m and 1.5 m deep for a family of five, as a rough idea); keep it well away from wells and borewells (15 m or more is a common rule) and leave a manhole for cleaning.

Water tank and sump

Need: About 135 litres per person per day for a city home. A family of five uses about 700 litres a day.
Sump: An underground RCC tank storing 1–2 days of water (5,000–10,000 litres), waterproofed inside, with a tight lid, kept away from the septic tank.
Overhead tank: Plastic (HDPE) or RCC, 1,000–2,000 litres, raised on the roof so that taps get pressure. Its weight full (1,000 litres = 1 tonne) must be planned on columns or beams.
Rain water: Many cities make rain-water harvesting compulsory: terrace water is filtered into a recharge pit or stored in the sump.

8Outdoor works

Compound wall

What: The boundary wall round the plot.
Typical: 1.5–2 m (5'–6½') high; often lower or with grills at the front. Either 230 mm brickwork throughout, or 230 mm piers about every 3 m (10') with 115 mm panels between, on a strip footing or small pad footings with a plinth beam. A coping on top sheds rain.
Watch: Build it on your own side of the boundary; leave weep holes at the bottom if soil is piled against it.

Gates

Typical: Car gate 3–3.6 m (10'–12') wide in two leaves, or sliding; pedestrian gate 900–1200 mm (3'–4'). Mild steel (MS) fabrication with primer and enamel paint, hung on RCC or steel posts strong enough for the swing.
Watch: Gates should open inward, not over the road.

Car parking

Typical: About 2.5 × 5 m (8' × 16½') per car, more if doors must open beside walls. Many bylaws require one parking space per house; in a north-facing plot it usually sits in the front setback or under a stilt floor.
Floor: 100–150 mm of PCC or RCC on compacted soil, or paver blocks; sloped gently to drain.

Paving

What: Hard surfaces for the drive, paths and around the house.
Typical: Interlocking concrete paver blocks 60 mm thick for paths and 80 mm for driveways, on a 50 mm sand bed over compacted soil or murrum. Slope away from the house (about 1:50), with a drain along the edge.
Why: Keeps rain water away from the plinth and the foundations.

Typical sizes at a glance

The sizes below are drawn to scale against each other, so you can compare them by eye. Bylaws and the National Building Code set minimums for some of them; comfortable homes usually go a little above.

Doors and windows

Doors are all 2100 mm (7') high so their tops line up with the windows' lintels. Sizes in mm, width × height, including the frame.

Room sizes

Living room 12' × 16' · 3.66 × 4.88 m · 192 sq ft

Master bedroom 12' × 14' · 3.66 × 4.27 m · 168 sq ft

Bedroom 10' × 12' · 3.05 × 3.66 m · 120 sq ft

Dining 10' × 10' · 3.05 × 3.05 m · 100 sq ft

Kitchen 8' × 10' · 2.44 × 3.05 m · 80 sq ft

Dog-leg stair 7' × 12' · 2.13 × 3.66 m · 84 sq ft

Car parking 8' × 16' · 2.44 × 4.88 m · 128 sq ft

Bathroom 5' × 8' · 1.52 × 2.44 m · 40 sq ft

Toilet (WC) 4' × 5' · 1.22 × 1.52 m · 20 sq ft

Pooja 5' × 5' · 1.52 × 1.52 m · 25 sq ft

Comfortable sizes for a small Indian home, all drawn to one scale (grid squares are 2' × 2'). Minimums under most bylaws are smaller: about 9.5 m² (100 sq ft) for a habitable room and 1.8 m² for a bathroom.

Stair risers and treads

The shaded band is where steps feel natural: twice the riser plus the tread comes to 600–630 mm. The dashed lines are the National Building Code limits for houses. Any point inside the band and the limits works; keep every step in a flight the same.

9Materials and quantities

The basic materials

Cement: Sold in 50 kg bags. OPC 43 or 53 grade for RCC; PPC (with fly ash) is popular for plaster, masonry and general work. Use within about 3 months, stored off the floor and away from damp.
Sand: Fine aggregate: river sand where it is still allowed, or M-sand (manufactured from crushed rock), with P-sand (finer) for plaster. It must be clean, without clay or salt.
Aggregate: Crushed stone (jelly, khadi, metal): 20 mm for most RCC, 10–12 mm for thin sections, 40 mm for PCC.
Steel: TMT bars, grade Fe500 or Fe500D (Fe550 also used), in 8, 10, 12, 16, 20 and 25 mm diameters, 12 m lengths. Weight per metre = d² ÷ 162 kg (d in mm): 8 mm 0.395, 10 mm 0.617, 12 mm 0.889, 16 mm 1.58 kg/m.
Bricks and blocks: Burnt clay bricks are bought per 1000; AAC and concrete blocks per piece or per m³.
Water: Clean, drinkable water for mixing and curing.

Concrete grades

"M" stands for mix and the number is the strength in N/mm² that a test cube reaches after 28 days. RCC must be at least M20. Nominal mixes are by volume of cement : sand : aggregate. Ready-mix concrete (RMC) and design mixes give better, more consistent concrete for slabs and footings.

Grade	Mix	Use	Cement per m³	Sand per m³	Aggregate per m³
M7.5	1:4:8	PCC beds under footings and floors	3.4 bags	0.47 m³ (17 cft)	0.95 m³ (33 cft)
M10	1:3:6	PCC, sub-floors, levelling	4.4 bags	0.46 m³ (16 cft)	0.92 m³ (33 cft)
M15	1:2:4	Non-structural: paving, sills, coping	6.3 bags	0.44 m³ (16 cft)	0.88 m³ (31 cft)
M20	1:1.5:3	RCC: footings, columns, beams, slabs, lintels	8.1 bags	0.42 m³ (15 cft)	0.84 m³ (30 cft)

How these are worked out: dry materials shrink when water is added, so 1 m³ of wet concrete needs about 1.54 m³ of dry material. Split 1.54 by the mix ratio: for M20, cement is 1.54 × 1 ÷ 5.5 = 0.28 m³ = 403 kg (cement weighs 1440 kg/m³) = 8.1 bags.

How quantities are estimated

A proper estimate (a bill of quantities, BOQ) measures every item from the drawings, multiplies by its material per unit, and adds wastage (around 2–5%):

Measure each item in its unit: excavation and concrete in m³ or cft, brickwork in m³, plaster, flooring and paint in m² or sq ft, steel in kg.
Convert to materials with the ratios above: bags of cement, m³ of sand and aggregate, numbers of bricks.
Steel comes from a bar bending schedule (BBS): every bar's length × weight per metre.
Price each material and labour item at current local rates.

Worked example: your house

Here is the foundation and the ground-floor outer walls of a real plan, worked through by hand: a 30' × 65' north-facing plot with a 22'6" × 42' ground floor (6.86 × 12.80 m = 945 sq ft, 87.8 m²) standing on about 20 pillars. Every footing uses the sizes above. Numbers are rounded; swap in the counts and lengths from your own plan.

Step 1 · Excavation

Pit side = footing 1.2 + 2 × 0.15 PCC projection + 2 × 0.3 working space = 2.1 m
One pit = 2.1 × 2.1 × 1.5 deep = 6.62 m³
20 pits = 6.62 × 20 = 132 m³ (× 35.3 ≈ 4,670 cft)
Most goes back as backfill. Left over per pit = PCC 0.225 + pad 0.432 + neck 0.093 ≈ 0.75 m³, so about 15 m³ to spread on site or cart away.

Step 2 · PCC beds, 1:4:8

One bed = 1.5 × 1.5 × 0.1 = 0.225 m³; 20 beds = 4.5 m³
Dry volume = 4.5 × 1.54 = 6.93 m³
One part = 6.93 ÷ (1 + 4 + 8) = 0.533 m³
Cement = 0.533 × 1440 kg/m³ = 768 kg ÷ 50 = 16 bags
Sand = 4 × 0.533 = 2.13 m³ (75 cft); 40 mm aggregate = 8 × 0.533 = 4.26 m³ (151 cft)

Step 3 · Footing pads, M20 (1:1.5:3)

One pad = 1.2 × 1.2 × 0.3 = 0.432 m³; 20 pads = 8.64 m³
Dry volume = 8.64 × 1.54 = 13.31 m³
One part = 13.31 ÷ (1 + 1.5 + 3) = 2.42 m³
Cement = 2.42 × 1440 = 3,485 kg ÷ 50 = 70 bags
Sand = 1.5 × 2.42 = 3.63 m³ (128 cft); 20 mm aggregate = 3 × 2.42 = 7.26 m³ (256 cft)

Step 4 · Steel in the footings

Bars each way = (1200 − 2 × 50 cover) ÷ 150 spacing + 1 = 8.3 → 9 bars
Bar length = 1.1 m + 2 × 0.1 m bent-up ends = 1.3 m
One footing = 2 directions × 9 × 1.3 m × 0.889 kg/m (12 mm) = 20.8 kg
20 footings ≈ 416 kg
Thumb-rule check: 8.64 m³ × 50–80 kg per m³ = 430–690 kg. Same ballpark; the engineer's bar bending schedule decides.

Step 5 · Neck columns

Height = footing top (−1.2 m) to plinth beam bottom (+0.15 m) = 1.35 m
One neck = 0.23 × 0.3 × 1.35 = 0.093 m³; 20 necks = 1.86 m³
Cement = 1.86 × 8.1 bags per m³ (M20) = 15 bags; sand 0.78 m³, aggregate 1.56 m³
Steel by thumb rule = 1.86 × 200 kg per m³ ≈ 370 kg

Step 6 · Plinth beam, 230 × 300

Outer walls = 2 × (6.86 + 12.80) = 39.3 m; inner walls about 25 m (measure yours); total 64.3 m
Concrete length between pillars = 64.3 − 20 × 0.3 = 58.3 m
Volume = 58.3 × 0.23 × 0.3 = 4.02 m³
Cement = 4.02 × 8.1 = 33 bags; sand = 4.02 × 0.42 = 1.69 m³; aggregate = 4.02 × 0.84 = 3.38 m³
Steel per metre: 4 × 12 mm bars = 4 × 0.889 = 3.56 kg, plus 8 mm stirrups at 150 (6.7 per metre, ~1.0 m each) = 6.7 × 0.395 = 2.64 kg; with 10% for laps ≈ 6.8 kg/m
Steel = 64.3 m × 6.8 ≈ 437 kg

Step 7 · Bricks in the ground-floor outer walls, 230 mm

One brick with its 10 mm joints = 0.24 × 0.125 × 0.085 = 0.00255 m³, so 1 ÷ 0.00255 = 392 bricks per m³; with 5% breakage ≈ 410
Mortar per m³ = 1 − 392 × (0.23 × 0.115 × 0.075) = 0.22 m³ wet → × 1.33 = 0.295 m³ dry → 1:6 gives cement 0.295 ÷ 7 × 1440 = 61 kg and sand 0.25 m³
Gross wall = 39.3 m long × 0.23 × 2.7 m high (plinth to roof beam) = 24.4 m³
Less openings: main door 2.2 m² + 6 windows 8.6 m² + 3 ventilators 0.8 m² = 11.6 m² × 0.23 = 2.7 m³
Less 14 pillars in the outer walls = 14 × 0.3 × 0.23 × 2.7 = 2.6 m³; less the lintel band = 39.3 × 0.23 × 0.15 = 1.4 m³
Net brickwork = 24.4 − 2.7 − 2.6 − 1.4 = 17.7 m³
Bricks = 17.7 × 410 ≈ 7,300; cement = 17.7 × 61 kg ≈ 22 bags; sand = 17.7 × 0.25 ≈ 4.4 m³ (156 cft)

Totals so far: foundation, plinth and outer ground-floor walls

Item	Volume	Cement	Sand	Aggregate	Steel
Excavation	132 m³	–	–	–	–
PCC beds	4.5 m³	16 bags	2.1 m³	4.3 m³	–
Footing pads	8.6 m³	70 bags	3.6 m³	7.3 m³	416 kg
Neck columns	1.9 m³	15 bags	0.8 m³	1.6 m³	370 kg
Plinth beam	4.0 m³	33 bags	1.7 m³	3.4 m³	437 kg
Outer walls (7,300 bricks)	17.7 m³	22 bags	4.4 m³	–	–
Total		156 bags	12.6 m³ (445 cft)	16.5 m³ (580 cft)	≈ 1.2 t

Add 2–5% for wastage when ordering. The roof slab, beams, columns above plinth, inner walls, plaster and flooring are measured the same way: volume × materials per m³.

Whole house: thumb rules per sq ft

For an early budget, builders multiply the built-up area by rough rates for an ordinary RCC-framed house. Use them as a sanity check on a proper estimate, not instead of one.

Cement0.4–0.5 bag / sq ft380–470 bagsfor 945 sq ftG+1 (1,890 sq ft): 760–950 bags

Steel (TMT)3.5–4.5 kg / sq ft3.3–4.3 tfor 945 sq ftG+1 (1,890 sq ft): 6.6–8.5 t

Sand≈ 1.8 cft / sq ft≈ 1,700 cftfor 945 sq ftG+1 (1,890 sq ft): ≈ 3,400 cft

Aggregate≈ 1.35 cft / sq ft≈ 1,280 cftfor 945 sq ftG+1 (1,890 sq ft): ≈ 2,550 cft

Bricks8–10 / sq ft7,600–9,500for 945 sq ftG+1 (1,890 sq ft): 15,000–19,000

Steel per m³ of concrete is another check: roughly 50–80 kg in footings, 80–100 kg in slabs, 100–160 kg in beams and 160–250 kg in columns. A 230 mm wall takes about 400 traditional bricks or 500 modular bricks per m³, and about a quarter of a cubic metre of mortar.

Where the money goes

A rough split for an ordinary specification. It varies widely: premium flooring, woodwork and fittings can push finishes past 40%, and poor soil can double the foundation.

By type of spend, materials are usually about two-thirds of the total and labour about one third, with steel and cement the biggest single materials. Builders quote a rate per sq ft of built-up area; it changes with city, specification and year, so get current local quotes and multiply by your area.

Coming to OctBuild: because the plan already knows every wall, footing, pillar, beam and opening, it can measure these quantities from your drawing instead of a thumb rule.

10Choosing materials

Each material below is listed with its common types, where each is used, its strengths and weaknesses, a rough price level, and how to check its quality on site. Price levels are relative within each table (₹ low, ₹₹ medium, ₹₹₹ high) and vary by region; get local quotes.

Cement

The grey powder that binds sand and aggregate into concrete and mortar. Sold in 50 kg bags; the type is printed on the bag.

Type	Used for	Pros	Cons	Price
OPC 53	RCC where early strength matters: slabs, columns, precast work	Gains strength fast, so formwork can come off sooner	More heat as it sets, so more shrinkage cracks if curing is poor; not ideal for plaster	₹₹ Medium
OPC 43	General RCC and masonry	Balanced strength and workability	Slower than 53 grade; less resistant to salts than blended cements	₹₹ Medium
PPC (fly-ash blended)	Foundations, masonry, plaster, and much house RCC	Lower heat, denser and more durable concrete, smoother plaster, usually cheaper	Slower early strength: keep props and curing longer (10–14 days)	₹ Low
PSC (slag blended)	Coastal sites, sulphate-rich or wet soils, foundations, sumps	Best resistance to chlorides and sulphates; low heat	Slow early strength; not stocked everywhere	₹ Low

Check on site

ISI mark, IS code and the cement type on the bag.
Manufacturing date on the bag: use within about 3 months.
No lumps; a hand pushed into the bag feels cool and smooth.
Store on planks off the floor, away from walls, at most 10 bags high, covered.

Steel (TMT bars)

Thermo-mechanically treated bars that carry the tension in RCC. The number is the yield strength in N/mm²; "D" means extra ductility.

Type	Used for	Pros	Cons	Price
Fe500	Standard reinforcement for houses	Widely available, well understood by site crews	Less stretch before breaking than the D grade	₹₹ Medium
Fe500D	Houses in earthquake zones III–V, and any frame where you want a margin	Bends further before breaking; tighter limits on impurities	Slightly dearer	₹₹ Medium
Fe550 / Fe550D	Heavier loads and taller buildings	Higher strength can save some steel	Only if the engineer designed for it; plain Fe550 is less ductile	₹₹–₹₹₹ Medium–high
CRS or epoxy-coated TMT	Coastal and very damp sites	Resists rust much longer	Costlier; epoxy coating must not be chipped	₹₹₹ High

Check on site

BIS mark, brand and grade rolled onto every bar.
Bend test: an 8–10 mm bar bent fully back on itself shows no cracks.
Weigh a 12 m bar: about 12 × d² ÷ 162 kg (12 mm ≈ 10.7 kg).
Light surface rust is fine; flaky, scaling rust is not. Store off the ground and covered.

Sand

Fine aggregate for concrete, mortar and plaster. Its cleanliness decides how strong the mix is.

Type	Used for	Pros	Cons	Price
River sand	Concrete, masonry, plaster	Rounded grains, easy to work	Mining is banned or restricted in many states; often contains silt, clay or salt	₹₹₹ High
M-sand (manufactured)	Concrete and masonry	Consistent grading, no silt, available everywhere	Angular grains need a little more water or admixture; poor batches carry too much dust	₹₹ Medium
P-sand (plastering)	Plaster only	Finer and washed: smooth plaster	Too fine for concrete	₹₹ Medium

Check on site

Silt test: shake sand in a jar of salty water and let it settle 3 hours; the silt layer on top should be under about 8% of the sand.
Rub a handful between your palms: clean sand does not leave a stain.
For M-sand ask for a washed, Zone II grading report.

Aggregate (jelly)

Crushed stone that forms the bulk of concrete. Size is chosen by how thick the member is and how close the bars are.

Type	Used for	Pros	Cons	Price
20 mm	Most RCC: footings, columns, beams, slabs	Strong, economical mix	Too big for thin, crowded sections	₹–₹₹ Low–medium
10–12 mm	Thin slabs, sunshades, precast, crowded steel	Flows between bars	Needs more cement for the same strength	₹–₹₹ Low–medium
40 mm	PCC beds, mass concrete	Cheapest concrete per m³	Not for RCC	₹ Low

Check on site

Cubical, angular pieces; few flat or long slivers.
Clean: no dust or clay coating (wash it if there is).
Hard: pieces do not crumble when hit with a hammer.

Bricks and blocks

The units the walls are built from. Weight, size and insulation differ a lot, and lighter walls also lighten the frame and footings.

Type	Used for	Pros	Cons	Price
Red clay brick	Any wall; the traditional choice	Strong, good thermal mass, every mason knows it	Quality varies kiln to kiln; heavy; uses topsoil	₹₹ Medium
Fly-ash brick	Any wall	Uniform size (less plaster), uses waste ash	Smooth faces bond less well; needs good curing	₹–₹₹ Low–medium
AAC block	Walls in framed buildings, especially upper floors	About a third the weight of brick, insulating, quick to lay	Needs thin-bed adhesive and care fixing heavy items; must be plastered well outside	₹₹ Medium
Solid concrete block	Compound walls, budget houses, ground floors	Strong, fast, cheap	Heavy and hot; can shrink and crack	₹ Low
Hollow concrete block	Partitions, compound walls	Lighter, cheaper, conduits run in the cores	Lower strength; harder to fix things to	₹ Low
Laterite stone	Kerala, Konkan, Goa: walls and compound walls	Local, cool, handsome when exposed	Hardness varies; porous, so protect from driving rain	₹–₹₹ Low–medium

Check on site

Clay bricks: even colour, sharp edges, a metallic ring when two are struck together, no cracks.
Drop a brick flat from about 1 m onto firm ground: it should not break.
Water absorption after 24 h soaking should be under about 20% of dry weight.
Blocks: check size, density certificate, and that concrete blocks are at least 28 days old.

Concrete grades

Concrete is chosen by strength and by how harsh its surroundings are (IS 456 "exposure"). Above M20, use a design mix or ready-mix (RMC).

Type	Used for	Pros	Cons	Price
M15	PCC under floors, paths, non-structural work	Cheap	Not allowed for RCC	₹ Low
M20	RCC in houses with mild exposure	Minimum grade for RCC; site-mixable	Too weak for coastal or wet exposure	₹₹ Medium
M25	Moderate exposure (humid, coastal away from the sea, wet soil), G+3 and above	More durable; less permeable	Needs controlled batching (RMC or weigh batching)	₹₹–₹₹₹ Medium–high
M30	Severe exposure (sea coast, aggressive soil), taller buildings	High durability and strength	RMC, design mix and good supervision	₹₹₹ High

Check on site

Slump test at the mixer: about 75–100 mm for hand-placed work; no extra water added on site.
Cast 3 test cubes per pour and get them tested at 7 and 28 days.
Vibrate it well; cure for at least 7 days (10–14 for PPC and PSC).

Roofing

The roof carries rain, heat and often a future floor; choose by climate and by whether you will build up later.

Type	Used for	Pros	Cons	Price
RCC flat slab	Most houses; terraces and future floors	Strong, usable terrace, easy to extend	Absorbs heat; needs waterproofing	₹₹ Medium
Filler slab	Single and two-storey homes	Clay pots or tiles replace useless concrete: 15–25% less concrete and steel, cooler	Needs an engineer and skilled crew	₹–₹₹ Low–medium
Sloped RCC with tiles	Heavy-rain and coastal areas	Sheds rain fast; traditional look	More formwork and finishing work	₹₹–₹₹₹ Medium–high
Metal sheets	Sheds, parking, terrace covers, budget roofs	Fast, light, cheap	Hot and noisy in rain unless insulated	₹ Low
Mangalore (clay) tiles on a frame	Traditional sloped roofs	Cool, breathable, sheds heavy rain	Tiles shift and leak; frame needs upkeep	₹₹ Medium

Check on site

Before a slab pour: steel spacing and cover blocks per drawing, conduits in place, slope set for drainage.
Sheets: check thickness (about 0.45–0.5 mm) and coating.
Tiles: no cracks, even colour, a clear ring when tapped.

Flooring

Choose by room use: wet areas need grip, high-traffic areas need hardness, and bedrooms can be softer.

Type	Used for	Pros	Cons	Price
Vitrified tile	Living and bedrooms; most of the house	Hard, low water absorption, many designs, big sizes	Slippery when wet (use matt or anti-skid in wet areas), feels cold	₹₹ Medium
Ceramic tile	Bathroom walls and floors, kitchen dado	Cheap, light	Softer, chips, absorbs more water	₹ Low
Granite	Stairs, kitchen tops, entrances	Very hard and long-lasting	Heavy, costly, can be slippery when polished	₹₹₹ High
Marble	Living and puja rooms	Elegant, cool	Soft, stains with acids, needs polishing	₹₹₹ High
Kota stone	Budget homes, utility, parking, outdoors	Tough, cool, naturally non-slip, cheap	Limited colours; needs polishing	₹ Low
Wood or laminate	Bedrooms in premium homes	Warm and quiet	Damaged by water and termites	₹₹₹ High

Check on site

All boxes for a room from the same batch and shade number.
Tap laid tiles: a hollow sound means poor bedding.
Joints kept even with spacers (2–3 mm); floors in wet areas fall to the drain.

Doors and windows

Frames and shutters face sun, rain, termites and daily wear; choose by where each opening is.

Type	Used for	Pros	Cons	Price
Teak	Main door, frames	Durable, stable, resists termites, looks rich	Expensive; check it is genuine, seasoned teak	₹₹₹ High
Sal and other hardwoods	Door frames	Hard, strong	Heavy; warps or cracks if not seasoned	₹₹ Medium
Flush door (IS 2202)	Inner room doors	Flat, cheap, easy to laminate or paint	Swells if it stays wet	₹–₹₹ Low–medium
WPC or PVC	Bathroom doors and frames, damp areas	Waterproof, termite-proof	Less strong; can sag if wide	₹–₹₹ Low–medium
uPVC windows	Most windows	Seal well, quiet, little upkeep	Quality varies by profile; dark colours can warp in heat	₹₹ Medium
Aluminium windows	Sliding windows, large glass	Slim, strong, durable	Conducts heat; thin sections rattle	₹₹ Medium
Steel (pressed or MS)	Frames, grills, budget windows, utility doors	Cheap, strong, secure	Rusts unless galvanised and painted, especially near the coast	₹ Low

Check on site

Wood: seasoned, no wide cracks or loose knots; anti-termite primer on faces touching the wall.
Flush doors: ISI mark and a solid core where hinges and locks go.
uPVC: profile wall thickness and steel reinforcement inside; aluminium: section thickness about 1.2 mm or more.
Stainless-steel or brass hardware, not plated mild steel.

Plaster and paint

Plaster gives the wall its surface; paint protects and colours it.

Type	Used for	Pros	Cons	Price
Cement plaster	Everywhere, inside and out	Durable, cheap	Needs 7 days of curing; cracks if it dries fast	₹ Low
Gypsum plaster	Inside dry rooms	Very smooth, fast, no curing	Not for bathrooms or outside walls	₹₹ Medium
Distemper	Budget interiors, rentals	Cheapest paint	Not washable; fades	₹ Low
Interior emulsion	Most interiors	Washable; low-odour options	Premium ranges cost more	₹₹ Medium
Exterior emulsion / elastomeric	Outside walls	Resists rain, sun and fungus; elastomeric bridges hairline cracks	Costlier; needs a good primer	₹₹–₹₹₹ Medium–high

Check on site

Plaster: no hollow sound when tapped; a straight edge shows a flat wall.
Let new plaster dry (about 4 weeks) before painting; use putty and primer first.
Sealed tins of one batch per wall; note coverage per litre on the tin.

Waterproofing

The cheapest insurance in a house. Pick a system by where the water comes from.

Type	Used for	Pros	Cons	Price
Integral compound	Added to concrete and plaster	Cheap, easy	Only reduces absorption; not a barrier on its own	₹ Low
Cementitious coating (2-part)	Bathrooms, balconies, sumps, tanks	Bonds to concrete; tiles can go on top	Rigid: cracks if the slab moves	₹₹ Medium
Liquid membrane (acrylic or PU)	Terraces, exposed roofs	Seamless and flexible; acrylic takes sun	PU needs protection from sun; recoat every few years	₹₹–₹₹₹ Medium–high
Bitumen membrane (APP/SBS)	Terraces, basements, sunken areas	Tough, proven	Needs a skilled crew to torch-lay and protect	₹₹ Medium
Brickbat coba	Terraces, under tiles	Slope plus insulation	Heavy; not waterproof by itself	₹ Low

Check on site

Surface cleaned and cracks filled before coating.
Coverage per m² as on the product sheet; turn up walls 300 mm.
Flood test for 24–48 hours before tiling over.

Plumbing pipes

Supply pipes carry pressure and sometimes heat; drainage pipes carry waste by gravity.

Type	Used for	Pros	Cons	Price
CPVC	Hot and cold water inside the house	Takes hot water, easy solvent joints	Brittle in cold or sun if left exposed	₹₹ Medium
uPVC	Cold water, outside lines, rising main	Cheap, does not rust	Not for hot water	₹ Low
PPR	Hot and cold water	Heat-fused joints rarely leak	Needs a fusion tool and trained plumber	₹₹ Medium
GI (galvanised iron)	Older houses; exposed outdoor runs	Strong	Rusts and scales inside; avoid in walls	₹₹ Medium
PVC SWR	Soil, waste and rain-water drainage	Cheap, smooth	Must be supported and sloped properly	₹ Low

Check on site

ISI mark and pressure class (for CPVC, SDR 11) printed on the pipe.
Pipes, fittings and solvent cement from the same brand.
Pressure-test every concealed line before plastering or tiling.

Electrical wire

Copper house wire, sized by load (see Services). The insulation type decides how it behaves in a fire.

Type	Used for	Pros	Cons	Price
FR PVC copper	Standard house wiring	Flame-retardant, widely available	Gives off dense smoke if it burns	₹₹ Medium
FRLS copper	Homes, especially multi-storey	Low smoke in a fire	Slightly dearer	₹₹–₹₹₹ Medium–high
HFFR / ZHFR copper	Premium homes, children's and elderly rooms	No toxic halogen fumes	Most expensive	₹₹₹ High
Aluminium wire	Avoid inside houses	Cheap	Loosens at joints and overheats	₹ Low

Check on site

ISI mark; a full 90 m coil.
Cut a sample: check the copper size and strand count against the label.
Colour code kept: red/yellow/blue phase, black neutral, green earth.

Choose by the kind of building

Typical choices for common situations. Several can apply at once (a G+2 house on the coast in an earthquake zone): take the stricter choice in each column.

Building	Foundation	Structure	Walls	Roof	Flooring	Doors and windows	Why
1-storey budget house	Stepped strip footing in brick or stone, or small pad footings on firm soil	Load-bearing 230 mm walls with RCC lintel and roof bands, or a light RCC frame; M20, Fe500	Red clay, fly-ash, laterite or solid concrete blocks	RCC or filler slab; sheets for sheds	Kota, ceramic or budget vitrified	Sal frames, flush doors, steel windows	Lowest cost with local materials; one floor does not need a heavy frame.
G+1 / G+2 family house (like yours)	Isolated RCC footings 1.2–1.5 m deep on PCC, plinth beams	RCC frame, M20 (M25 if exposure is moderate), Fe500 or Fe500D	230 mm brick or fly-ash outside, 115 mm inside; AAC upstairs to save weight	RCC slab with terrace waterproofing and a heat-reflective coat	Vitrified; granite for stairs and kitchen top	Teak main door, flush inner doors, WPC bathroom doors, uPVC or aluminium windows	Well-understood, easy to build and easy to extend upward if the footings and columns are designed for it.
G+3 and above	Engineer-designed: larger, combined or raft footings, or piles, from a soil test	RCC frame M25–M30, Fe500D or Fe550D, ready-mix concrete	AAC or fly-ash (lighter walls reduce frame and foundation size)	RCC slab with a membrane	Vitrified, granite common areas	Aluminium or uPVC windows, fire-rated main doors where required	Loads, wind and earthquake forces grow with height; permits need structural certification; plan for a lift.
Coastal or humid area	Footings in M25+ with 50 mm cover; PSC or PPC cement	RCC frame M25, CRS or epoxy-coated TMT, generous cover	Well-burnt brick or solid block; 20 mm outside plaster with waterproofing additive	RCC (often sloped) with a membrane; wide overhangs	Vitrified or Kota; avoid wood	uPVC or powder-coated aluminium, stainless-steel hardware, no bare mild steel	Salt air rusts steel and damp rots wood; dense concrete and cover protect the bars.
High-rainfall area	Plinth raised 600 mm or more, DPC, drains round the house	RCC frame M20–M25	Laterite or brick with water-repellent exterior paint	Sloped RCC with clay or Mangalore tiles, or a sheet roof over the terrace; eaves and chajjas 600 mm+	Anti-skid tiles outside; vitrified inside	Hardwood or uPVC with drip moulds and deep sunshades	Shed water fast and keep walls and foundations dry.
Black-cotton or expansive soil	Footings below the active zone (often 2 m+), under-reamed piles, sand or murrum cushion; engineer decides	RCC frame with plinth, lintel and roof bands	Lighter AAC or fly-ash blocks	RCC slab	On well-compacted murrum fill, never directly on black soil	Any; leave small clearances so frames do not jam	The soil swells when wet and shrinks when dry; keep moisture steady with drains and an apron.
Earthquake zone (III–V)	Footings tied together with plinth beams	Ductile detailing (IS 13920), Fe500D, M25; regular, symmetric plan; no soft storey or floating columns	Lighter blocks; lintel and roof bands; partitions tied to the frame	Monolithic RCC slab; no heavy tanks on cantilevers	Any	Keep openings away from corners and wall ends	The frame must bend without breaking, and a lighter building attracts smaller earthquake forces.
Hot-dry climate	Standard footings	RCC frame	Thick brick, cavity walls, AAC or stabilised earth for insulation and mass	Filler slab or insulated RCC (brickbat coba, white reflective coat, terrace garden or double roof)	Kota or stone: cool underfoot	Small west-facing openings, deep shades, jaalis, light-coloured outside	Thermal mass and insulation keep the afternoon heat out.
Rental or low-maintenance	Standard footings	RCC frame, M20–M25	Fly-ash or clay brick	RCC with a good membrane	Double-charge vitrified, granite stairs	WPC or uPVC doors, aluminium windows, stainless hardware; washable paint	Hard-wearing finishes that are cheap and quick to repair between tenants.
Premium home	Engineered footings from a full soil test	RCC frame M25+, Fe500D, ready-mix concrete	AAC with insulation, or exposed brick	Insulated RCC; terrace garden with root-barrier membrane	Marble, engineered wood, large-format tiles	Teak, double-glazed uPVC or aluminium, quality hardware	Comfort and finish matter more, and the budget allows long-life systems.

How to decide

Soil. Get the soil test first. Weak, filled or black-cotton soil changes the foundation, and sometimes the walls and floors too.
Number of floors. Plan the footings and columns for every floor you might ever add, even if you build one now.
Climate. Coast and humidity call for durable concrete and rust-free fittings; heavy rain for sloped roofs and overhangs; heat for insulation and thermal mass.
Budget. Spend on what is hard to change later (foundation, frame, waterproofing, wiring, pipes); finishes can be upgraded later.
Maintenance. Who will look after the house? Choose finishes that you, or tenants, can keep clean and repair.
Local availability. Local materials and skills (laterite in Kerala, Kota in Rajasthan, fly-ash near power plants) are cheaper and better built.
Speed of construction. AAC blocks, ready-mix concrete and sheet roofs save weeks; traditional methods save money where labour is cheap.

Glossary of site terms

AAC block: Autoclaved aerated concrete: a light, insulating block for walls.
Backfilling: Refilling dug pits and trenches with soil, in watered and rammed layers.
BBS: Bar bending schedule: a list of every steel bar, its shape, length and weight.
BOQ: Bill of quantities: the itemised list of work and materials used to price a job.
Brickbat coba: Broken bricks in mortar, laid on a terrace to form a slope and insulate.
Built-up area: Floor area including the thickness of walls. Carpet area is the usable floor inside the walls.
Centering and shuttering: Temporary formwork and props (steel plates or plywood) that hold wet concrete in shape.
Chajja (sunshade): A thin RCC projection over a window to keep off sun and rain.
Coping: The sloped top of a parapet or compound wall that sheds rain water.
Cover: The concrete between the steel and the outside face, which protects steel from rust and fire: 15–50 mm depending on the member.
Cover blocks: Small concrete spacers tied under and beside the steel to keep the cover.
Curing: Keeping new concrete, plaster or brickwork wet for 7–14 days so the cement gains strength.
Dado: Tiling or a finish on the lower part of a wall, as above a kitchen counter.
DPC: Damp-proof course: a waterproof layer at plinth level that stops ground moisture rising in walls.
FAR / FSI: Floor area ratio or floor space index: total floor area of all storeys ÷ plot area, as allowed by bylaws.
FFL: Finished floor level: the top of the finished floor, the zero for heights inside the house.
Footing: The widened base of a column or wall that spreads its load onto the soil.
Founding level: The depth at which the footing rests: the bottom of the PCC bed.
GL / NGL: Ground level / natural ground level of the site.
Ground coverage: The percentage of the plot that the building's footprint may cover.
Lap: The overlap where two bars are joined, usually about 50 times the bar diameter.
Lintel: A small beam over a door or window opening that carries the wall above.
M-sand: Manufactured sand made by crushing rock, used in place of river sand.
M20: A concrete grade: 20 N/mm² strength at 28 days. The minimum for RCC.
Murrum: A gravelly, reddish soil used for plinth filling and sub-bases.
Neck column: The part of a column below plinth level, between the footing and the plinth beam.
Parapet: A low wall round the edge of a terrace or balcony, about 900–1000 mm high.
PCC: Plain cement concrete: concrete without steel, used for beds and sub-floors.
Plinth: The part of the building between ground level and the ground-floor level. Plinth level is its top, typically 450 mm above ground.
Plinth beam: An RCC beam at plinth level that links the columns and carries the ground-floor walls.
RCC: Reinforced cement concrete: concrete with steel bars, strong in both compression and tension.
RMC: Ready-mix concrete, batched in a plant and delivered in a transit mixer.
SBC: Safe bearing capacity: the load per unit area the soil can safely carry.
Setback: The open space required between the building and each plot boundary.
Sill: The bottom edge of a window opening, and its height above the floor.
Skirting: A low tile or stone strip along the bottom of walls.
Soak pit: A pit filled with stones that lets treated waste water seep into the ground.
Stirrups / ties / rings: Loops of thin bar (usually 8 mm) round the main bars of beams and columns.
Sump: An underground water storage tank. OHT is the overhead tank.
TMT: Thermo-mechanically treated steel bars, the standard reinforcement; Fe500 means 500 N/mm² yield strength.
Toothing: Bricks left stepped out at the end of a wall, so that a later wall can bond into it.
Waist slab: The sloping RCC slab of a staircase, under the steps.

This page is a guide for learning, not a specification. Have the structure designed and checked by a qualified structural engineer, follow your local bylaws and the National Building Code, and supervise the work on site.