Prefab housing — everything is decided before the first panel.
Flat-pack and container-based units. The awkward thing about this category: the building is assembled 8,000 km from where it is drawn, by people who cannot ask you a question. So every dimension, every service penetration and every joint has to be closed on paper first. That is where the work is.
What we buy
- Flat-pack modular units — wall, roof and floor cassettes, bolted or cam-lock, one to three storeys.
- Container-based units — modified ISO frames for site offices, canteens, accommodation, ablution blocks.
- Bathroom and kitchen pods — inserted into the frame, or supplied as a stand-alone module.
- Envelope systems — insulated sandwich panels, cement boards, fibre-cement cladding, standing-seam roofing.
- Service packages — pre-cut conduit, pre-plumbed wet walls, distribution boards, lighting points set to drawing.
- Accessories — stairs, canopies, balustrades, corner trims, sealant and flashing kits.
The thing that actually goes wrong
The unit arrives and it is well made. The panels are square, the finish is good, the insulation is in. It just does not fit the site — because the drainage outlet is 200 mm from where the drawing shows it, or the door swings against a wall that was built after the order was placed.
Nobody is at fault in the way that a defect is a fault. The factory built what the drawing said. The site built to a revision the factory never received. On a modular project, errors do not appear as rework — they appear as a unit that cannot be connected.
How we handle it
Before quoting, we get three things in writing: the architectural drawing with dimensions, the site constraints (access, crane, maximum module size, transport route) and the service schedule. From these we produce a single dimension sheet that the factory prices and the site can check. That sheet, not the marketing brochure, becomes the contract document.
The first unit is treated as a prototype. It is photographed and measured before the rest of the run starts, and the measurements go back to you with any deviation flagged. It is far cheaper to move a waste outlet on unit one than on unit forty.
Before loading we check: panel count against the packing list, corner and joint alignment, whether the loose service items are actually in the container, and whether the sealant and flashing kits match the specification. Flat-pack failures are usually missing parts, not bad parts.
Questions specific to this line
Can the units be certified for our market?
+Sometimes, and the answer is specific, not general. Structural compliance, fire class of the sandwich panel core, electrical certification and sanitary approval are four separate questions with four separate answers. We will tell you which ones the factory already holds evidence for, which can be tested, and which will need a local engineer's sign-off after arrival. Do not accept "CE marked" as an answer to any of them.
What is the maximum size that ships economically?
+For flat-pack, the constraint is usually the panel length rather than the module footprint — a 40 ft high-cube will take panels up to about 12 m, and anything longer becomes a flat-rack or break-bulk shipment. For container-based units, standard ISO dimensions keep freight cheap; anything wider than 2.44 m starts costing multiples of the normal rate. We will model both before recommending one.
How do you check quality on something this large?
+In stages, because you cannot inspect a building at the end. We check the frame and cassette dimensions before cladding goes on, the insulated panel installation and sealing before the services are run, and the services and fit-out before packing. Each stage produces photographs and measurements. If a stage fails, production stops until it is corrected — that is the only point at which it is cheap to correct.
Who handles the installation on site?
+Not us — we are on the buying side, not the building side. What we can do is make sure the installation instructions, the fixing schedule and the connection details leave the factory in a language and format your site team can work from, and that the loose components match the packing list. Where it is justified, we can arrange for a factory technician to attend, but that is a separate commercial arrangement.