Departmental Proximity Planning: Warehouse to Cutting to Sewing

Every garment factory has a hidden transport bill, paid daily in footsteps, trolley pushes, forklift trips, and waiting time. The bill is set by one decision more than any other: which departments sit next to each other. Put the two departments that exchange the most material at opposite ends of the building, and the factory pays for that mistake on every trip, every shift, every day. Put them adjacent, and the same work costs a fraction. Departmental proximity planning is the method for making that decision from measurement instead of from habit or from whichever space happens to be free.

The logic is simple but it is often skipped. Managers place departments where space is available, where the last tenant left a room, or where the building shape suggests. Those reasons have nothing to do with material traffic, and the factory then spends years compensating with extra handlers, extra trolleys, and extra overtime. A proximity plan built on counted trips and measured distances reverses that: the heaviest traffic gets the shortest legs, and the whole factory gets quieter, faster, and cheaper to run.

Flow intensity is the volume of material traffic between two departments. It can be counted three ways: trips per day, load per trip, or travel metres per day. The third is the most useful, because it combines frequency and distance into one ranking number. To measure it, list every department pair that exchanges material: warehouse to cutting, cutting to sewing, sewing to finishing, finishing to packing, and the return flows of empties and rejects. Count trips per day for each pair across a full week, not a single day, because delivery days and changeover days carry very different traffic from quiet production days.

Then measure the real route distance for each pair. Walk the trolley route with a measuring wheel, including lifts, stairs, doorways, and detours. Never use the straight line on the drawing: a pair that looks 20 metres apart on paper can be 68 metres apart on the floor once the lift journey and the corridor detour are included. Multiply daily trips by real distance to get daily travel metres per pair, and rank the pairs from highest to lowest. That ranking is the proximity plan in numerical form.

A proximity diagram is a sketch that turns the ranking into a floor arrangement. Place the highest-ranked pair adjacent first, then fit the next pair, and so on, working down the ranking. Only a few pairs can be truly adjacent, because a department has only so many neighbours, so the diagram forces honest trade-offs. The pairs at the top of the ranking win adjacency. The pairs at the bottom accept longer legs, because their traffic is light enough that the extra distance costs little.

Draw the diagram at the same time as the flow spine from the unidirectional layout study. The two tools agree: departments in process order along one spine will also be the high-flow pairs, because material flows along the sequence. Where they disagree, trust the measured ranking. A factory where trims issue generates more trips than expected, for example, may need the trims store closer to sewing than the textbook sequence suggests.

The warehouse to cutting leg is almost always one of the two heaviest flows in a garment factory, and it is the heaviest in load terms. Full fabric rolls are bulky and heavy, they arrive on pallets or roll trolleys, and they must reach the cutting tables without damage to the fabric or delay to the cutting plan. Every metre on this leg is multiplied by roll weight: a handler pushing a 200 kilogram roll trolley 55 metres works far harder than a handler carrying a bundle 55 metres. That is why cutting belongs beside the warehouse, with a wide, straight, level route between them and no lift journey if the building allows it.

The warehouse side of the leg needs its own discipline. Rolls must be issued in shade-lot order, with the issue counter facing the cutting room so that the handler journey starts at the door, not at the far end of a deep store. A warehouse that issues from its far corner adds a hidden leg inside the store itself, and that leg repeats on every roll. Measure the issue counter to cutting table distance, not the warehouse centre to cutting centre distance, or the plan will understate the real journey.

Cutting to sewing is usually the highest-trip-count leg in the factory: hundreds of bundles per day, each one a shade-matched set that must arrive complete and in order. The leg deserves the shortest, clearest route in the building, because bundle delays starve sewing lines directly. A sewing line waiting for bundles loses output minute by minute, while a warehouse waiting for rolls merely delays the next cutting marker. That asymmetry is why cutting to sewing outranks warehouse to cutting in trip count terms even though rolls are heavier.

Bundle discipline matters as much as distance on this leg. Bundles should travel in sequence, on trolleys sized to the bundle count, with a marked lane that does not cross finished goods. Where floors differ, a bundle chute or a dedicated conveyor beats a shared lift, because a shared lift introduces a queue that varies with the whole building traffic. If a lift is unavoidable, give bundle traffic a priority window or a dedicated lift car during peak feeding hours, and measure the waiting time explicitly so the cost of the lift is visible.

Sewing to finishing carries the same bundle count as cutting to sewing, because every sewn bundle must be finished, but the character of the flow changes. Finished bundles are lighter and cleaner, and the risk shifts from starvation to contamination and damage: a finished bundle dragged through a dusty corridor or stacked under a leaking roofline loses value that sewing already added. The finishing leg therefore needs a clean, covered, marked lane, and finishing itself should sit beside packing on the same floor as the loading dock wherever possible.

Finishing to packing is a carton flow, not a bundle flow, and its trip count is lower but its load is bulkier. Cartons need pallet or cage trolleys and a staging area beside the dock that does not block the packing tables. A common failure is placing packing far from the dock because the packing hall fit an empty room, which forces every carton through the whole factory at the last step. Measure the carton journey with the same method as the bundle journey, and the cost of that placement becomes obvious.

A woven shirt factory in Ashulia measured its four main legs along real trolley routes. Warehouse to cutting ran 40 trips per day at 55 metres, giving 2,200 metres of daily travel. Cutting to sewing ran 120 trips per day at 68 metres, giving 8,160 metres. Sewing to finishing ran 120 trips per day at 42 metres, giving 5,040 metres. Finishing to packing ran 60 trips per day at 30 metres, giving 1,800 metres. The old total was 17,200 metres per day across 340 trips.

After rebuilding the proximity plan, cutting moved beside the warehouse at 12 metres, sewing moved beside cutting at 15 metres, finishing moved beside packing at 10 metres, and packing moved beside the dock at 8 metres. The new daily travel was 480 plus 1,800 plus 1,200 plus 480 metres, totalling 3,960 metres per day. The saving was 13,240 metres per day, which is 77 percent of the old total. The cutting to sewing leg alone fell from 8,160 metres to 1,800 metres per day, and the lift journey disappeared from that leg entirely, removing its waiting time as well as its distance.

Proximity is a strong rule, but it is not absolute. Safety and quality rules override it wherever they apply. Flammable stores, chemical stores, and boiler rooms keep their separation distances regardless of traffic. Dusty cutting stays away from finished goods and from inspection areas, even if the ranking suggests adjacency. Noisy areas stay away from QC and office areas. These overrides are not exceptions to be regretted. They are part of the plan, recorded on the same diagram with their reasons, so that a future manager does not undo them in the name of a shorter route. Any specific separation distance or clearance required by a safety rule must be verified against the current factory safety standard and buyer requirement before the plan is finalised, because standards change and a layout built on an outdated clearance will fail its next audit.

Count trips for a full week, by pair, including return flows of empties and rejects. Measure real route distances with a measuring wheel, including lifts and detours. Compute daily travel metres per pair and rank the pairs. Draw the proximity diagram from the ranking, placing the heaviest pairs adjacent. Apply safety and quality overrides and record their reasons on the diagram. Recompute the proposed daily travel total and present the saving as the business case. Pilot one department move first, verify the measured saving at real load, and only then move the remaining departments and paint the permanent markings.