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An isolated footing bar bending schedule lists the bottom mat — bars along the length and bars along the width — with their cutting length, count and weight. Enter the footing size, thickness, cover, bar diameters and spacing, and an end bend if the drawing shows one. The editor opens with the worked example below (unless you already have a schedule on this device) — change any figure, or add more members. Need it in Excel with formulas? Download the free bar bending schedule Excel template.
Nothing here yet. Add your first member. Each member is one beam, column, slab (and so on) with its bars; if you have six identical beams, add one and set "identical members" to 6.
The example is a beam, a column and a footing.
Assumptions used
- Bend deductions (× bar diameter, per bend)
- 45° = 1d, 90° = 2d, 135° = 3d (SP 34). If you give a bend radius, 45° and 90° bends use the exact geometric deduction 2(r + d)·tan(θ/2) − θ(r + d/2) instead; hooks always use the table.
- Hook length (× bar diameter)
- 90° = 12d, 135° = 10d
- Minimum hook length (IS 13920)
- 75mm floor, applied to the 135° hook only
- Unit weight (IS 1786)
- d² / 162 kg per metre
- Cutting lengths
- rounded half-up to the nearest 10mm, once
- Development length
- Ld = 0.87 fy × d / (4 × 1.6 × τbd), IS 456 Cl 26.2.1, used exactly — not rounded to a whole multiple of d, which can fall short of the code by up to half a diameter.
- Tie leg arrangements resolved
- 2 legs = 1 × closed_rect; 3 legs = 1 × closed_rect, 1 × single_leg; 4 legs = 1 × closed_rect, 2 × single_leg
- Stock length for splicing
- 12000mm. A bar longer than this is split into stock-length pieces and the lap steel at each splice is ADDED to the total length and weight — so for a spliced bar, total length is more than cutting length × bar count, by design.
- Splice lap length
- the greater of Ld and 30d (IS 456 Cl 26.2.5.1(c), flexural tension). If a grade pair has no tabulated bond stress, a bar needing a splice is reported as uncomputable rather than spliced with a zero lap.
- Closer stirrups / ties near the ends
- If you give an end-zone length and spacing, the run is counted as end zone + middle + end zone without counting the boundary bars twice. Zone lengths are never assumed.
- Bent-up (cranked) bars
- two 45° cranks, each adding 0.42 × the centreline offset D' (member depth − 2 × cover − bar diameter), on top of the anchored straight length. Centreline basis, so no extra bend deduction. Not yet hand-verified.
- Continuous beams
- Bottom bars per span: bent down into end supports, Ld/3 past the face at interior supports (IS 456 Cl 26.2.3.3(a)). Top bars continuous, bent down into both end supports, spliced with billed laps when over stock length. Not yet hand-verified.
- Column bars
- Floor height + lap carried up; a crank into the column above adds the slope length at 1 in 6; ground-floor starter bars add the footing depth less cover and an L-foot, with the 90° bend deducted. Circular columns: hoops are π × centreline diameter plus hooks; a helix adds 1.5 turns at each end.
- Lintel, staircase, pile cap
- Lintel bars run opening + bearing each side less cover; the stair is a one-flight waist slab with main bars along the slope (√(run² + rise²)); the pile cap is a plain block with a bottom mat and an optional straight top mat. Step concrete, pile heads and side-face bars are not modelled.
- Steel density ranges (kg/m³)
- beams 100–200, columns 150–280; other members are shown without a verdict — no published range has been checked for them, and a guessed range would be worse than none
A calculation aid, not a design. It applies standard IS conventions to the numbers you enter and does not check that they satisfy any code requirement. A qualified engineer must check and sign off the schedule before any bar is cut.
Worked example — 1500 × 1500 mm isolated footing
A 1500 × 1500 mm footing, 450 mm thick, 50 mm cover, with 12 mm bars at 150 mm both ways, straight, M25 / Fe500. These figures are computed by the same code the editor above runs — they are not typed in.
| Bar mark | Bar | Shape | Dia | Dimensions (mm) | Cutting length | Total bars | Weight |
|---|---|---|---|---|---|---|---|
| F1/1 | Bottom mat bar along L | Straight | 12 mm | A 1400 | 1400 mm | 10 | 12.44 kg |
| F1/2 | Bottom mat bar along W | Straight | 12 mm | A 1400 | 1400 mm | 10 | 12.44 kg |
Total steel 24.89 kg in 1.013 m³ of concrete.
- Footing shape
- Prismatic (flat top) assumed — volume is L × W × thickness with no sloped or stepped top, no pedestal, and no deduction for the column stub.
How does the calculator work out each footing bar?
- Bar length
- footing dimension − 2 × cover. With an end bend, a leg is added at each end and the two 90° bends are deducted at 2d each.
- Number of bars
- floor((other dimension − 2 × cover) ÷ spacing) + 1 — 1400 mm at 150 mm is 10 bars.
- Sloped footing
- give the edge depth and the flat top size and the concrete volume is worked out as a block plus a frustum. The bottom mat does not change.
- Weight
- total length × d² ÷ 162 kg per metre, d in mm.
Bend deductions, hook lengths and rounding are listed in full under "Assumptions used" above.
Where can you learn the footing calculation step by step?
- Turn spacing into a steel quantity — a lesson in the free bar bending schedule course.
Frequently asked questions
- How do you calculate the bars in an isolated footing?
- Each bar is the footing dimension less the cover at both ends. The number of bars is the other dimension less two covers, divided by the spacing, rounded down, plus one. Do it once for the bars along the length and once for the bars along the width.
- Should footing bars have bends at the ends?
- Follow the drawing. Many footings show a bend or an L at each end of the bottom bars. Enter its leg length and the calculator adds it and deducts the bends; leave it blank for straight bars.
- Does the footing schedule include the column starter bars?
- No. Starter bars belong to the column. Add them on a column member by giving the footing depth, cover and foot length, so they are counted once.
- What cover is used for a footing?
- The cover you enter. IS 456 asks for at least 50 mm in footings; check the drawing, which may specify more where the concrete is cast against soil.
Bar bending schedule for other members: slab · beam · column · every member type.