A Construction Schedule You Can Actually Maintain

Most construction schedules on small and mid-size Indian sites die within three weeks of being made. Someone prepares a colourful Gantt chart in Excel before the project starts, it goes into the kickoff file, and nobody opens it again until the client asks why the slab is a month late. The problem is not that the site team is lazy — it is that the schedule was built as a presentation, not as a working tool. This lesson shows you how to build a schedule that a two-person site team can actually maintain, and how that schedule becomes the backbone of billing and project control.

Why site schedules die

A schedule dies when updating it costs more effort than the value it gives. The usual killers:

• Too many activities. A 200-line schedule for a G+1 house cannot be updated weekly by a site engineer who also handles material, labour and the client. It gets abandoned.
• Durations were guesses. If the plaster duration was typed in as "2 weeks" without checking the plaster area against mason output, the schedule loses credibility the first time reality disagrees.
• No link to money. If the schedule does not drive billing, material ordering or labour mobilisation, nobody has a reason to keep it honest.

The fix is a bar chart of 15 to 25 activities, durations computed from quantities and crew output, and a fixed weekly routine to update it.

Build the activity list from the BOQ

Do not invent activities from imagination. Your BOQ (Module 4) already lists every item of work with quantities. Group BOQ items into activities that a single trade crew executes as one block:

1. Mobilisation, layout and setting out
2. Excavation, PCC and footings
3. Columns up to plinth, plinth beam, backfill
4. Ground-floor columns
5. Ground-floor slab (shuttering, steel, pour)
6. First-floor columns and slab
7. Blockwork or brickwork, both floors
8. MEP rough-in (conduits, sleeves — runs parallel)
9. Internal plaster
10. External plaster
11. Waterproofing and floor screeds
12. Flooring and tiling
13. Doors, windows and fixtures
14. Painting, final MEP fit-out, cleaning and handover

Fifteen to twenty-five activities is the sweet spot: coarse enough to update in half an hour, fine enough that a slipping activity is visible before it becomes a crisis.

Durations from crew output, not from hope

Every duration must come from a simple division: quantity divided by daily crew output. Use indicative norms and correct them with your own site data after the first month. Common indicative outputs on Indian residential sites (always calibrate to your own crews):

Worked example — three durations for a G+1 house (about 2,000 sqft built-up):

• Brickwork: total 230 mm brickwork = 68 cum. Crew of 4 masons at 1.0 cum per mason-day = 4 cum/day. Duration = 68 / 4 = 17 working days, so plan 3 weeks including a Sunday and one rain day.
• Internal plaster: measured plaster area = 940 sqm. Crew of 6 masons at 9 sqm per mason-day = 54 sqm/day. Duration = 940 / 54 = 17.4, say 18 working days — 3 weeks.
• Ground-floor slab cycle: slab area 145 sqm. Shuttering at 2 carpenters covering about 20 sqm/day of formwork takes roughly 8–10 days; steel fixing for about 1.9 tonnes at 300 kg/day with two fitters takes 6–7 days overlapping the last days of shuttering; pour is 1 day. Plan the cycle as 3 weeks from start of shuttering to pour.

Outputs also depend on how labour is engaged. A thekedar's regular gang that moves site to site with him will hold these norms; daily-wage naka labour picked up for a peak week typically runs 20–30 per cent slower and needs closer supervision. If your plaster plan assumes six thekedar masons and you get four plus two naka hands, redo the duration — do not hope.

Then add a buffer. On residential work a 15–20 per cent time buffer for rain, festivals and labour absence is realistic — a 26-working-day month, not 30. A schedule without buffer is a schedule that is wrong on day one.

The weekly routine that keeps it alive

A schedule survives only if updating it is a fixed ritual. The routine that works on small sites:

1. Every Saturday, mark actual progress on each running activity — a simple percentage or "done up to first-floor lintel level" note against the bar.
2. Compare against the baseline bar. Anything more than one week behind gets a written reason: drawing not released, labour shortage, payment delay, rework.
3. Prepare a two-week lookahead: which activities start in the next 14 days, and what each one needs — drawings, material on site, subcontractor mobilised, previous work cleared. Chase those needs on Monday, not on the day the crew stands idle.
4. Agree catch-up actions with named owners: add one mason gang, work the Sunday, resequence external plaster before flooring.

This 30-minute loop is also your early-warning system for cost: an activity that is late almost always becomes an activity that is over budget, because idle supervision, extended scaffolding hire and de-mobilised crews all cost money.

Link the schedule to money

The schedule is not only about time — it is the skeleton of your billing plan. Each activity finishing is a billing event: footings complete, plinth complete, each slab cast, brickwork complete, plaster complete. If you mark the expected work value against each activity, the schedule becomes a month-by-month cash-flow forecast (Module 5 covered the S-curve). A contractor who knows that the first-floor slab pour unlocks roughly Rs. 9–10 lakh of billing will fight to hold that date; a contractor with no schedule discovers the slippage in the bank balance.

This also disciplines the client side: advance notice that a big bill is coming next month prevents the "certified but unpaid" trap that stalls sites.

How the schedule protects you in a dispute

Delay disputes are decided on records, not memories. A dated baseline schedule plus weekly updates with written reasons — "drawing for staircase not released", "client payment for RA-2 pending 24 days", "marble selection awaited from owner" — is the contractor's defence against liquidated damages and the owner's evidence when the contractor blames everyone else. In the RERA era this cuts both ways: a developer commits a possession date in the registered agreement, so a maintained schedule with client-side and force-majeure delays recorded contemporaneously is what an adjudicating officer or arbitrator will actually read. An unmaintained schedule protects nobody; whoever kept the better records usually wins the delay argument.

Common mistakes

• Scheduling in days but reviewing in months. Review weekly or the schedule is history, not control.
• No buffer, then blaming rain every single month.
• Hiding slippage by quietly stretching bars. Keep the baseline visible and draw actual progress against it — the gap is the information.
• Treating parallel trades as sequential. MEP rough-in, blockwork and the next floor's structure overlap; a purely sequential chart inflates the duration and nobody believes it.
• One giant "finishing" bar. Finishing is half the project duration; break it into plaster, flooring, doors and windows, painting.

What comes next

A schedule tells you when work should happen. The moment it does happen, it must be measured and recorded — because unrecorded work cannot be billed, and memory is not evidence. The next lesson covers the measurement book: the one document that converts physical progress into money.