Concrete and steel calculator (lantar aur chhat)

Cement, sand and crush for a lintel, slab, beam or column, and the steel counted from your drawing.

WhatsApp the builders team All calculators Self-build guide

Concrete and steel (lantar, chhat, beam, column)

Cement, sand and crush for a lintel, slab, beam, column or footing. For steel, enter the bar size and spacing from your approved structural drawing and it counts the bars, lengths and kilograms; a rough per-cubic-foot figure is there only for early budgeting.

Enter size as Length (ft) Width (ft) Depth / thickness (in) Volume (cu ft) Mix Steel Element Bottom bars Bottom bar spacing (in, both ways) Top / extra bars over supports Top bar spacing (in) Top bars cover this % of the slab Beam width (in) Beam depth (in) Top bars (count) Bottom bars (count) Main bar size Stirrup size Stirrup spacing (in) Column height (ft) Column width (in) Column depth (in) Vertical bars (count) Vertical bar size Tie size Tie spacing (in) Add for laps and cutting % Element (typical steel) Steel kg per cu ft Bar size for weight

For a beam or column, "length" above is the beam length or, for a column, use the column height field; width × depth give the section. Slab steel needs the length × width entry.

Common questions

How much cement goes into a 100 sq ft, 5 inch slab?

That is 41.7 cu ft of concrete. At 1 : 2 : 4 it takes about 7.5 bags of cement, 18 cu ft of sand and 37 cu ft of 3/4 in crush — roughly 18 bags per 100 cu ft of concrete.

Where do the bar sizes and spacing come from?

From the structural drawing that was approved with your plan, prepared by an engineer for your spans and loads. This calculator counts the steel in that drawing so you buy the right amount; it does not decide the sizes. If your drawing says something the mistri wants to change, ask the engineer, not the mistri.

What do 3 sutar, 4 sutar mean?

Sutar is one-eighth of an inch: 3 sutar = 3/8 in (#3, 9.5 mm), 4 sutar = 1/2 in (#4, 12.7 mm), 5 sutar = 5/8 in. A 40 ft bar of 3 sutar weighs about 6.8 kg, 4 sutar 12.1 kg, 5 sutar 18.9 kg — weigh a bar when buying; underweight bars are common.

How long before the shuttering comes off?

Slab props stay 21 days, long beams 28 days. Cure by ponding water on the slab from the next morning for at least 14 days.

More free tools

House builderDraw your rooms on your plot, drag things into place, then tap anything to see the tiles, paint, cement and wire it needs.
Society legal statusSearch any housing society in Islamabad or Rawalpindi and see whether it is approved, NOC in process, or illegal, with the approved area.
Plot priceBuying or selling? Pick the society and plot size for an estimated price range and the FBR reference value.
Cost by plot sizePick the area, plot size and dimensions; get cement bags, steel kg, bricks, labour, grey-structure and finishing cost.
TilesRooms in, tiles and boxes out, with wastage, bedding mortar and cost.
PaintLitres, gallons and drums for walls and ceilings, with primer and putty.
Daily cement mixBags and rehri of sand for today's plaster, brickwork or tile bedding, batch by batch.
Bricks & blocksBricks, concrete blocks or AAC blocks for a wall, with mortar or adhesive.
WiringMetres and 90 m bundles by wire size for the whole house.
Cost estimateA grey-structure and finishing budget for your covered area at the rates you are quoted today.
ChecklistFourteen stages: what to buy, what to check with the mistri, and what to photograph before it is covered.

Want a builder to check the numbers?

Blackfire Real Estate & Builders builds on labour or contract rate in Islamabad and Rawalpindi and does one-off site checks for people building themselves.

0371-7581455

Message on WhatsApp Read the self-build guide

All quantities on this site are estimates for planning and buying. Site conditions, workmanship and brands change the real figures. Structural sizes and reinforcement must come from your approved drawings and engineer.