Chargeable, usable, carpet: get this right before anything else
Every BKC number you will be quoted — rent, maintenance, fit-out — is per square foot of chargeable area, and chargeable area includes a share of the lobby, the core, the plant and sometimes the podium. Density planning uses usable area. Confusing the two produces a plan that does not fit.
| Measure | What it includes | Typical BKC ratio | What it is used for |
|---|---|---|---|
| Chargeable area | Usable plus a loaded share of core, lobby and services | 100% | Rent, maintenance, fit-out quotations |
| Usable area | The floor inside your demise | 72 – 80% of chargeable | Space planning and density |
| Carpet area | Usable less internal walls, columns and shafts | 66 – 74% of chargeable | Furniture layout, seat counts |
A 25,000 sq ft chargeable floor at 76% is 19,000 sq ft usable and roughly 17,500 sq ft carpet. Plan seats against the last number, budget against the first.
Worked example: 18,000 sq ft chargeable Grade-A floor
Financial services tenant, 13,700 sq ft usable, 165 seats, twelve meeting rooms, a client floor at the lift lobby and a dealing area of twenty-two positions.
| Scope | ₹ lakh | Detail |
|---|---|---|
| Landlord charges, supervision, protection and passes | 41.5 | Includes the fit-out deposit administration and security vetting |
| Workstations, storage, dealing desks and soft seating | 148.0 | 165 seats; dealing positions at 1,600 mm with integrated cable management |
| Ceiling, lighting and controls | 79.0 | Client floor detailed separately; daylight dimming on the glazed perimeter |
| Electrical, UPS, small power and data containment | 72.5 | Dual-source distribution, UPS at 1.8 kVA per dealing position |
| HVAC modification, VAV rebalancing and BMS tie-in | 64.0 | Nominated vendor package, passed through at cost |
| Fire detection and sprinkler modification | 52.0 | Nominated vendor; every head relocated to the new ceiling grid |
| Partitions, glazed fronts, acoustic doors | 38.5 | Boardroom at Rw 52; twelve meeting rooms at Rw 45 |
| Flooring and client-floor stone | 31.5 | Carpet tile throughout, stone to the lift lobby and client area |
| Pantry, wellness room and washroom upgrade | 18.0 | Barista pantry for 165; two wellness rooms |
| Management, commissioning and contingency | 13.0 | Includes integrated testing and the O&M handover set |
| Total, ex-GST | 558.0 | ₹3,100 per sq ft on 18,000 sq ft chargeable |
Add 18% GST. Nominated-vendor packages — HVAC, fire and BMS — are ₹116 lakh of this, 21% of the total, priced by the landlord's contractors and passed through.
Grade-A delivery inside the landlord's manual
The fit-out manual, and what it actually controls
- Who may touch base-build services. Fire detection, sprinklers, the BMS, AHUs, VAV boxes and the chilled-water circuit are the landlord's nominated vendors' work. Their lead times and their availability are the project's critical path, which is why we place those orders at design freeze and not at mobilisation.
- When noise is permitted. Core drilling, chasing, demolition and anchor fixing typically run 10pm to 6am, because the floors above and below are occupied. That is 25–35% more expensive per hour and it is disclosed in our quotation as its own line, not buried in a rate.
- How material moves. Booked service lifts in slots, escorted routes, delivery-bay time limits, and security vetting for every worker with documents lodged days ahead. A crew member whose pass has lapsed does not enter, so we hold a single fixed crew list for the duration.
- What the ceiling void must preserve. Sprinkler coverage, smoke detection zoning, access to every valve and damper, and the landlord's clearances above the grid. Ceilings get a services-coordination drawing signed by the landlord before a single hanger goes in.
- What comes out at the end. Reinstatement to shell, with the definition of shell written into the lease. We keep the as-built and the reinstatement schedule from week one.
Running approvals in parallel, which is the whole trick
The single largest avoidable cost in BKC is sequencing. Tenants commonly complete detailed design, then submit for landlord approval, then order the nominated packages — and lose four to six weeks to a process that could have run concurrently. Our programme submits the services concept for landlord comment while the furniture and finishes are still being selected, places the nominated-vendor orders at design freeze, and books the first six weeks of night slots before the contract is signed.
The second avoidable cost is security vetting. Every worker needs documents lodged and a pass issued, and a site that rotates labour weekly spends a day a week at the security desk. We submit one fixed crew list before mobilisation and add to it only by exception, which on an eighteen-week programme is worth roughly three weeks of lost access.
For the district including its small residential pocket, see interior designers in BKC. Our workplace planning standards citywide are on office interior designers in Mumbai, and the contracting side on office fit-out contractors.
Grade-A fit-out by Greenbox Design Studio.
Frequently asked questions
Why do BKC fit-outs cost so much more than Powai or Andheri?+
About a fifth of the difference is base-build coordination — nominated vendors for fire, HVAC and BMS at landlord rates, supervision charges, security and access administration. Another part is the night-work premium on all noisy scope. The rest is specification: BKC tenants build client floors, dealing areas and boardrooms that a suburban office does not have.
What is a nominated vendor and can I use my own contractor instead?+
A contractor appointed by the landlord for base-build systems — sprinklers, fire detection, BMS, HVAC. You cannot substitute them; doing so voids the base-build warranty and, in most BKC leases, breaches the fit-out manual. We coordinate their programme, hold them to dates and pass their cost through transparently in the BOQ.
How much of my chargeable area can I actually plan on?+
Seventy-two to eighty per cent as usable area, and sixty-six to seventy-four per cent as carpet once internal walls, columns and shafts are deducted. Ask the landlord for the measured usable area in writing before you plan seats. We have seen density plans fail by fifteen seats because they were built on the chargeable number.
Can any work happen during the day in a BKC tower?+
Yes — everything that is quiet. Joinery installation, furniture, flooring, painting, cabling pulls and commissioning all run in normal hours. What moves to the 10pm–6am window is core drilling, chasing, demolition and anchor fixing. A well-planned BKC programme keeps the night scope to about a fifth of the labour hours.
How long does an 18,000 sq ft BKC floor take?+
Eighteen to twenty-four weeks from design freeze, with the nominated-vendor packages on the critical path. Landlord approval of the services drawings is the most common cause of slippage, which is why we submit the services concept for comment before the design is finished rather than after.