Why a lessons post rather than another case study
The project itself — brief, plan, photographs, outcome — is on the Sleepmax office case study and we would rather not repeat it. What that page cannot usefully carry is the internal version: the six things that went differently from how we expected, and the changes we made to our own standard specification and process because of them. Every studio has a list like this and most do not publish it.
Lesson 1 — phase against the client's calendar, not the construction sequence
We planned the phasing the way a fit-out is normally phased: zone by zone, in the order that suited the trades. What we should have done first was sit with the operations lead and map the business's own month — the days when the floor could not tolerate noise, the week when the auditors were in, the two days a month when the whole team was in for reviews. Construction logic and business logic produced different sequences, and the business logic should have won.
What changed: we now ask for a three-month operations calendar before issuing a phasing plan on any occupied fit-out, and we build the noisy works around it rather than asking the client to work around us. It costs nothing at planning stage and it has removed the single most common source of friction on occupied projects.
Design and build under one accountable roof
Lesson 2 — partitions to slab, without exception
This is the specification we now hold hardest. Stopping a partition at the ceiling grid leaves a continuous air path over the top of the wall, and the room's acoustic performance collapses to roughly that of the open plan — a room that measures Rw 42 on paper delivers something closer to Rw 28 in use. It is a favourite value-engineering cut because it saves visible money on a BOQ and the consequence does not appear until people are using the rooms.
| Partition build-up | Rated Rw | Delivered in use | Cost per sq ft, ex-GST |
|---|---|---|---|
| Gypsum to ceiling grid only, 75 mm stud | Rw 40 | ~Rw 26–30 | ₹480–₹720 |
| Gypsum to slab, 75 mm stud, single board | Rw 40 | Rw 36–38 | ₹620–₹880 |
| Gypsum to slab, 100 mm stud, double board, 50 mm infill | Rw 48 | Rw 44–46 | ₹880–₹1,350 |
| Single-glazed 10 mm to ceiling | Rw 32 | ~Rw 24 | ₹490–₹1,050 |
| Double-glazed 10+12+10 to slab with head seal | Rw 45 | Rw 40–43 | ₹2,400–₹3,600 |
The difference between the first and second rows is about ₹160 per sq ft of partition. On a 6,000 sq ft floor with eight rooms that is roughly ₹2.2 L, and it decides whether the rooms work. The single-glazed rate is what we have billed on completed commercial fit-outs, banded and brought to October 2026; the gypsum and double-glazed build-ups are market figures.
Lesson 3 — brief storage in linear metres
We took a storage brief in cabinet counts, which is how clients naturally express it: 'four filing units for accounts, two for HR'. What arrived on site, once the team actually moved in, was a volume of physical files nobody had measured. The units were the right number and the wrong capacity.
What changed: we now ask departments to measure the linear metres of files, samples and stock they are currently holding, add a documented growth allowance, and we specify to that figure. It takes an hour of somebody's time, it produces a number rather than an impression, and it has eliminated the post-handover storage scramble entirely.
Lesson 4 — the client-facing route is a design object
The reception, the route from reception to the meeting rooms, and what a visitor sees on the way, form a sequence — and on Sleepmax we designed the reception and the meeting rooms well and the twelve metres between them as circulation. A visitor's experience of a company is that walk. We now draw it as a sequence with its own elevations: what is visible at each turn, where the brand appears, what is deliberately screened, and where daylight falls.
- Draw the visitor route as a set of four or five views, not as a corridor on a plan.
- Decide at each point what is visible of the working floor. Some clients want the floor on show; others want it entirely screened. Nobody wants it accidental.
- Put the highest-quality material where a hand touches: the reception desk edge, the meeting-room door pull, the chair arm.
- Keep the route to under about 35 m from the lift lobby to the primary client-facing room, or add a legible waypoint.
Lesson 5 — commission the services before the client moves anything in
We had HVAC balanced and signed off, and then the client's own IT team installed rack equipment that changed the heat load in one room by a meaningful margin. That was not anyone's failure of goodwill, it was a sequencing gap: the balancing happened against the drawing's assumptions rather than against the equipment that would actually be in the room. We now ask for the IT and equipment schedule with its heat loads before commissioning, and re-balance after the racks are live rather than before.
Lesson 6 — the thing we would still do the same way
Off-site joinery fabrication. Almost all the fixed furniture was built in the workshop and installed in assemblies, which compressed the on-site programme substantially and kept the dust and noise off an occupied floor. On every occupied fit-out since, we have pushed the proportion of off-site work higher. It is the single most useful lever available on a live premises, it does not cost more, and clients feel it immediately.
The useful part of a finished project is not the photographs. It is the four things you will specify differently on the next one.
Greenbox commercial fit-out lead
What we would specify differently on the same brief today
- Partitions to slab in all enclosed rooms, priced in at concept so it is never a value-engineering candidate.
- Double the number of one- and two-person call rooms. The 2026 requirement is materially higher than the brief assumed at the time.
- NRC 0.70 ceiling tile across the open plan rather than NRC 0.50, at about ₹45 per sq ft more.
- A storage schedule in linear metres, signed off by each department head.
- Commissioning and air balancing scheduled after the client's equipment is in, with a return visit priced into the contract.
- The visitor route drawn as elevations at concept stage, alongside the plan.
Selected work by Greenbox Design Studio. Tap any image to enlarge.
Frequently asked questions
Where can I see the full Sleepmax office project?+
On our Sleepmax office case study page, which covers the brief, the plan, the materials and the photographs. This post is the complement to it — the internal lessons and the specification changes we made afterwards, which a case study page is not really the place for.
Why do partitions need to run to the slab?+
A partition stopping at the ceiling grid leaves a continuous air path over the wall, so sound passes above it and the room's delivered performance drops from around Rw 40 to something nearer Rw 28. Taking it to slab costs roughly ₹160 per sq ft of partition more — about ₹2.2 lakh on a 6,000 sq ft floor with eight rooms — and it is the difference between a meeting room and a decorated one.
How do you phase a fit-out in an occupied office?+
Against the client's operations calendar first and the construction sequence second. We ask for three months of the business's own diary — audit weeks, full-team review days, client visits, month-end — and plan noisy works around it. Zone-by-zone construction logic and business logic produce different sequences, and on an occupied floor the business logic should win.
How should a company brief its storage requirement?+
In linear metres of files, samples and stock currently held, measured department by department, plus a documented growth allowance. Cabinet counts are how people naturally express it and they are unreliable — the right number of units at the wrong capacity is the outcome. Measuring takes an hour and removes the post-handover storage scramble.
Does off-site joinery really shorten a fit-out?+
Substantially, on an occupied floor. Building fixed furniture in a workshop and installing it as assemblies removes days of cutting, dust and noise from the client's working environment, and it does not cost more — often slightly less, because workshop conditions are more efficient than a site corner. It is the single most useful programme lever on a live premises.