Customisation is the part of a factory-built building where buyers expect the most flexibility and meet the most constraint. A capsule can be customised extensively inside, and very little outside — because the exterior is governed by the transport envelope and the structural system. Knowing which side of that line you are on saves weeks.
The line: what is flexible and what is fixed
On the fixed side: body width (3.3 or 3.5 m), external height (3.2 m), and the structural logic of the frame. These are tooling and transport decisions, not design preferences. A request to make a unit 3.8 m wide is not a customisation, it is a new product — it will not fit standard container or road transport, and it resets the jigs.
On the flexible side: internal layout, partition positions, wet core location and size, glazing arrangement within the existing structural bays, finishes throughout, electrical layout and circuit count, kitchen configuration, furniture, external colour and coating, signage, and the climate package. That is a long list, and it covers almost everything a buyer actually wants to change.
Layout: the cheapest customisation and the most valuable
Interior layout changes are cut on the same jig as the standard plan, so they cost drawing time rather than production time. Within an existing model envelope you can usually move the wet core to either side, change whether the bed is longitudinal or transverse, replace a wardrobe run with a desk, or drop a partition to make one larger room. Each of those changes what the unit is for, which is worth more than any finish upgrade.
Two layout constraints are structural rather than stylistic. The wet core needs to sit where the floor can take the load and where the waste run has fall to the outlet — moving it across the unit may not be possible on a flat-floor design. And load-bearing partitions cannot simply be deleted; the frame handles it, but the ceiling and floor decks may need additional members, which is a drawing revision rather than a preference.
Glazing: the biggest visual lever
Within the existing bays, the glazed area can range from a single window to a full-height wall. This is the change that most affects how a unit photographs and how it performs thermally, and it is worth being deliberate about. A full-height glazed end wall sells a view and costs insulation; in a cold climate it needs a high-performance sealed unit and a heat pump sized for the additional loss, and it may need exterior shading on the exposed side. Specify both together or the room will overheat in summer and condense in winter.
Finishes and equipment
- External coating colour — within the coating system's colour range, not outside it. A custom colour usually means a minimum order quantity.
- Interior lining and flooring — composite panels and commercial-grade flooring hold up in rental use better than natural surfaces.
- Wet core — tray versus tiled, shower size, extraction, and whether the WC is wall-hung.
- Electrical — circuit count, socket positions, voltage and frequency for the destination market, smart switching.
- Climate — heat pump versus resistive, capacity for the climate zone, and ventilation with or without heat recovery.
- Furniture and fixed joinery — usually cheaper to source at the factory than locally, because it is cut to the plan.
How the OEM process actually runs
- Brief. Site, climate, use, floor area, unit count, and the destination market's electrical standard. A brief that omits the climate and the voltage produces a quote that has to be redone.
- Concept and quotation. Model selection and a specification summary, with exclusions listed. This is where the boundary of the price is set.
- Drawing set. Plan, elevations, wall section, electrical single-line diagram, water and waste layout, finish schedule. You sign this. Everything after this point is production.
- Sample or material confirmation. Coating colour, flooring, panel finish. Getting this wrong is expensive and entirely avoidable.
- Production. Frame, panel and shell, first fix, wet core and interior, test and pack. Hold points at each stage, with photographs.
- Pre-shipment inspection. Electrical continuity, water pressure test, door and window operation, and a walk-through video if you cannot attend.
- Shipping and documentation. Covered separately in the import guide.
Where lead time is lost
Not in production. Production is a schedule, and a competent factory holds it. Lead time is lost in the two places where the buyer has control: drawing approval and changes after approval. A change made after the frame is cut does not add a week at the end — it sends the unit back to an earlier stage and takes a slot that was allocated to someone else. If the project has a fixed opening date, freeze the drawings before paying the deposit, not after.
The second loss is material selection. A custom coating colour with a minimum order quantity, or a flooring that has to be imported, can add weeks before production even starts. Standard options ship from stock.
MOQ, tooling and what a small order really costs
A single custom unit is possible on most models, because the changes are drawing-led rather than tooling-led. What drives cost up on small orders is everything around the unit: a container that is not full, a custom colour, a bespoke furniture package, and engineering time that is the same whether it serves one unit or twenty. If you are buying several units, ask for the price at one, five and ten — the curve tells you where the fixed costs sit and it is often steeper than buyers expect between one and five.
Protecting the design
If you are commissioning a bespoke layout, put the drawing set and the specification under a simple confidentiality agreement before you share them, and confirm in writing who owns the drawings produced for your project. This is standard practice with reputable factories and it costs nothing to ask for. A supplier who resists a confidentiality clause on your own project drawings is telling you something.
A brief that gets a useful answer first time
- Destination country and city, and the climate the unit will sit in
- Electrical standard: voltage, frequency, plug type
- Use: rental, staff housing, residence, amenity space
- Floor area target and unit count
- Must-have layout features and any accessibility requirement
- Finish direction, with two or three reference images
- Site access constraints: route width, crane position, foundation type
- Target delivery window
Related
Supplier selection is a separate discipline and is covered in the China OEM supplier guide. For the range you are customising within, see the M-Series and Y-Series pages, and the size guide for floor areas. Send us the brief above and we will come back with a layout drawing rather than a catalogue page.
