Cost to build a shipping container house — what the price is made of

Quick answer

There is no single cost to build a shipping container house, because the price is eight layers, not a rate per square metre. The layers are the shell or the unit itself, any structural modification, the envelope and insulation, the interior fit-out, the MEP, the foundation and site works, the freight and lifting, and the compliance work. A converted ISO box and a new-build detachable unit carry the same eight, but in different proportions: the converted box starts with a cheap used shell and spends on bespoke steelwork and site labour, while the detachable unit is a production item priced per set with a published loading count.

The practical consequence is that two quotes for the same 6,058 × 2,438 mm footprint can differ by a factor without either supplier being wrong, because one is quoting a box and the other is quoting a building. Read the layers, ask which ones are in, and compare the delivered cost per square metre of usable floor.

Two products, one search

Before the price means anything, decide which product the price is for. The table below sets the two side by side on the things that move the number.

Converted ISO container against a new-build detachable container house
Question	Converted ISO container	Detachable container house
What the shell is	A used general-cargo box built and type-tested to ISO 1496-1, with corner fittings to ISO 1161 and a CSC safety approval plate for transport.	A new hot-dip galvanised steel frame with bolted connections and sandwich panel infill — the standard unit is 6,058 × 2,438 × 2,591 mm, the 40 ft unit 12,192 × 2,438 × 2,591 mm.
What the price is built from	Shell purchase plus cutting, reinforcement design, insulation, lining, fit-out, and site labour — an individually engineered conversion.	A per-set price for a production unit: frame, panels, floor, door, window, electrical, packed for shipping.
Structural work	Every opening interrupts a load path in the wall that carries the box; each one needs design and reinforcement to EN 1993-1-1.	Openings are set in the panel and frame system at the factory, to the drawing, before dispatch.
How it travels	As one assembled box, occupying a full container slot or a flat rack, with a lifting weight at the top of the transport range.	Flat-packed: four sets per 20 ft and eight sets per 40 HQ for the standard unit, confirmed in the loading plan.
Assembly at destination	Conversion work is usually done near the site, so the labour, the welding and the finishing all happen where you can see them — and pay for them.	Bolted assembly, no site welding, with a crew working from the assembly sequence.
After the first site	Cut and welded, so it is a one-way structure; moving it means moving a building.	Designed to be dismantled, restacked and re-shipped, which turns part of the spend into a re-deployable asset.

The ISO references are to the standards that govern the box as a transport unit: ISO 1496-1 for specification and testing, ISO 1161 for corner fittings, ISO 668 for the series 1 external dimensions. Sizes and loading counts for the detachable units are the figures published on our detachable container house page.

The eight layers in the price

Whatever product you end up buying, the money goes into these eight places. Ask a supplier to mark each one as included, excluded or priced separately — the answer is more informative than the total.

Shell or unit. A used box is bought by grade and condition; a detachable unit is bought as a set. This is the only layer where the converted route usually starts cheaper, and it is also the layer with the most variable quality: a box's remaining coating life and its history of cargo and repairs are not visible in a photograph.
Structural modification. On a converted box this is the layer that surprises people. Removing a side wall to open the unit up takes away part of what makes the box stiff, so the opening has to be framed and the frame designed — the calculation is a steel design to EN 1993-1-1, and it is engineering time, not carpentry time. On a detachable unit this layer is absorbed into the factory frame design, which is why it does not appear as a line.
Envelope and insulation. A steel box is a continuous thermal bridge: the frame runs from the outside skin to the inside face, so an internal lining needs a thermal break or a service void to keep the inner surface above the dew point. Insulation thickness and core decide both comfort and fire classification, and the panel core is classified to EN 13501-1 — the class that applies to the product you buy is the one on its declaration, not a general claim about the material.
Fit-out. Partitions, floors, ceilings, kitchen and bathroom, joinery. This layer is where budgets move most, and it is the least comparable between suppliers, because two fit-outs described in the same words can use very different board, finishes and hardware.
MEP. Electrical distribution, lighting, sockets, water, drainage, ventilation and air conditioning. On a detachable unit the electrical is part of the unit price at a basic level and the rest is added; on a conversion every run is site work.
Foundation and site works. Almost never in a supplier's price. A container house needs a level, drained base that will not settle, and the connection points for water, power and drainage have to exist before the unit lands.
Freight and lifting. Priced with the order, because it depends on the port, the volume and the packing. This is where flat-packing changes the arithmetic: the standard detachable unit packs four to a 20 ft and eight to a 40 HQ, so one 40 HQ slot delivers eight units of 14.77 m² gross plan area each, against one assembled 40 ft box at 29.72 m². That is the same slot carrying roughly four times the floor area, and it is the single biggest structural difference in delivered cost.
Compliance. Documents, testing and inspection. On the box side the CSC plate covers transport handling only, so occupancy, fire and structure fall to the building code where the unit is installed. On the supply side the file is the usual set — see the certifications page for the documents a project can request and inspection for how they are checked.

The two plan areas in layer 7 are arithmetic on the published envelope: 6,058 × 2,438 mm = 14.77 m² and 12,192 × 2,438 mm = 29.72 m². They are gross figures taken from the outside of the unit, not usable floor; the difference between the two, and how panel thickness reduces the internal area, is set out in container house size in metres.

What a container house quote usually leaves out

The fastest way to make two quotes comparable is to write the exclusions down. These are the items that are site-specific and therefore normally outside a supplier's figure:

Items normally outside a unit price
Item	Why it is not in the unit price	Who prices it
Foundation and ground works	Depends on soil, drainage and frost depth at the plot, none of which the supplier has seen.	Local groundworks contractor
Crane or telehandler	Depends on access, lift radius and whether the unit can be set directly from the truck.	Local plant hire
MEP connections to the site network	Depends on where the services are and what the local authority requires.	Local trades
Customs duty, clearance and port charges	Depends on the tariff line, the value declared and the destination.	Freight forwarder / broker
Permits and inspections	Depends on the jurisdiction and the use class of the building.	Local professional
Site labour beyond assembly	Depends on who provides the crew and what access they get.	Main contractor

A quote with no exclusions list is not a complete quote, it is an unfinished one. The delivered cost is the number that matters, and it only exists once these rows are filled in by someone who has priced them.

The structural question that moves a converted box's price

Most of the variance in a conversion quote sits in one place: what has to happen to the steel when the box stops being a box. Four points decide it.

Openings are structural events. The side walls of a general-cargo container take part in carrying the box, so a large opening is a framed opening, designed to EN 1993-1-1. A supplier who quotes openings without asking for the size, position and number is quoting an assumption.
Corner fittings are not to be touched. Lifting and securing loads enter at the corner fittings specified in ISO 1161. Cutting or welding into them compromises the one part of the unit that everything else is lifted by, and it is also the part a crane or a twistlock depends on at destination.
Coating life is a cost that arrives later. A used box's paint system has already spent years in service, and coastal or industrial sites sit in the higher corrosivity categories of ISO 12944-2. Where the coating has to be renewed to a stated category, that is a line in the budget, and it is the line most often forgotten. New galvanised steelwork on our units is specified to a hot-dip coating under ASTM A123, with the coating mass and the corrosivity category named in the specification rather than assumed.
Condensation is designed out, not wished away. A steel skin with insulation against it will condense on the cold side unless there is a thermal break or a ventilated void. On a conversion this usually means an internal frame and lining, which costs internal floor area as well as money.

None of this makes a conversion a bad idea. It makes it an engineering project with a bill attached, and the bill is predictable once the openings and the site are known.

Why a flat-packed unit prices differently

A detachable container house is not a cheaper box; it is a different business model. The unit is built as a frame-and-panel system, so the structural design is amortised across every unit sold rather than bought once per project, and the packing is part of the design rather than something that happens afterwards. Three consequences follow.

Freight is charged per set, not per building. Four sets per 20 ft and eight per 40 HQ for the standard unit means the shipping cost is divided across eight units in a 40 HQ slot.
Site labour is assembly, not construction. Panels bolt to a galvanised frame with no site welding, so the crew is sequencing kits rather than fabricating. The same property is what makes the unit dismantlable later.
Part of the spend stays recoverable. A unit that can be restacked and re-shipped has a residual value at the end of a project, which is a different total cost of ownership from a welded conversion that can only be demolished or sold with the land.

The flat-pack container house cost guide covers the same layer logic for the flat-pack range, and detachable against flat pack sets out which of the two suits which site. Loading can be checked before ordering with the container loading calculator.

How to compare two quotes line by line

Two quotes for the same unit count are rarely written to the same scope. Six checks settle it:

Is the footprint the same kind of number? External envelope or internal clear area? A quote on external area and a quote on usable floor are not comparable, and the gap is set by wall build-up.
Is freight in, and to which port? A unit price without a port is a factory figure, and the delivered cost is the only one that competes.
Is the wet room in? A bathroom pod is a large share of a small unit's price, and it is easy to leave on one side of a comparison.
What is the panel core and thickness? EPS and rock wool behave differently on fire classification to EN 13501-1, and the thickness drives both the price and the internal area.
What is the electrical scope? A distribution board and a few sockets is not the same as a full lighting and HVAC design.
What is the lead time counted from? Quoted per project and counted after deposit and drawing sign-off, which means the clock starts at a defined event rather than at the enquiry — the lead time guide explains what sits inside it.

What to send with a container house enquiry

A firm price needs inputs, not adjectives. Seven items are enough for a quotation with a loading plan and a lead time:

The drawing, or a sketch with the unit count and how the units sit together
The use — site office, dormitory, canteen, shop, clinic — because it sets the fit-out and the wet areas
The panel core and thickness, or the fire and thermal performance the project has to meet
Doors, windows and any opening larger than a standard unit's
The electrical and plumbing scope, and whether a wet room pod is required
The destination country and port
The site: coastal or inland, and whether the units will be moved to another site later

Send a drawing for a firm container house quote

The unit variants, panel options and loading counts are on the detachable container house page, with the flat-pack and expandable range alongside it and shops and kiosks for retail use. Minimum order quantity and how it is set are covered in MOQ for container houses, delivery and unloading in how a prefab house is shipped and unloaded, and a site-office version of the same cost logic in portable site office container cost.

Frequently asked questions

How much does it cost to build a shipping container house?

There is no single figure, because the price is a stack of eight layers rather than a rate per square metre: the shell or unit, any structural modification, the envelope and insulation, fit-out, MEP, foundation and site works, freight and lifting, and compliance. Two quotes for the same footprint can differ by the layers one of them leaves out. Ask for a line-item quote that names which of the eight layers it covers, and for the destination port, because freight and lifting are priced with the order.

Is a shipping container house cheaper than a detachable container house?

Not automatically, and the comparison has to be made on delivered cost per square metre of usable floor rather than per box. A used ISO container already exists, but every opening cut into it is bespoke structural work, it carries the coating and condensation behaviour of a steel tube, and it travels as one assembled box occupying a full container slot. A detachable container house is a production item: panels bolt to a galvanised frame with no site welding, the standard unit packs flat at four sets per 20 ft and eight sets per 40 HQ as published on our product page, and the units can be dismantled and re-used on another site, so part of the cost is recoverable asset rather than one-way spend.

What does a container house price usually not include?

Commonly excluded are the foundation and ground works, crane or telehandler hire at destination, the connection of water, power and drainage to the site network, customs duty and clearance, local permits and inspections, and site labour beyond the assembly crew. Each of these is site-specific and cannot be quoted by a supplier who has never seen the plot. Ask for the exclusions list in writing; a quote that has none is not complete, it is unfinished.

Can you cut doors and windows into a shipping container?

Yes, and it is standard practice, but every opening interrupts a load path in a structure whose walls are part of its strength. Openings need to be designed and reinforced to EN 1993-1-1, Eurocode 3, and the corner posts and corner fittings should not be cut at all, because that is where the lifting and securing loads enter, as specified in ISO 1161. Ask for the reinforcement detail with the quote, not after the steel has been cut.

Does the CSC plate mean a container is suitable to live in?

No. The safety approval plate under the International Convention for Safe Containers, 1972 certifies the unit for transport handling and stacking, and its Approved Continuous Examination Programme records the periodic examinations that keep it in transport service. It says nothing about occupancy, fire performance or thermal comfort. Once the box stops travelling, those questions move to the building code of the site, and that is the code a converted container has to be assessed against.

How many detachable container units fit in one container?

For the standard detachable unit, four sets pack into a 20 ft container and eight sets into a 40 HQ, flat-packed, as published on the detachable container house page. That count is confirmed for the specific order in the loading plan before the container is sealed, because panel thickness, fit-out and packing method all change it.

What decides the price of one detachable container house?

The size, the panel core and thickness, the doors and windows, whether a wet room pod is included, the electrical and plumbing scope, the finish level, the quantity, and the destination. Those are the inputs behind the per-project quote. A price quoted without them is an assumption, and the quotation stage is where the specification is confirmed against the drawing.

What is the fastest way to get a firm price?

Send the drawing or a sketch with the unit count, the destination country and port, and the specification items that matter to the project. That is enough to return a quotation with a loading plan and a lead time, rather than a range.

Sources

ISO 668, Series 1 freight containers — Classification, dimensions and ratings: the external envelope of the 20 ft and 40 ft series 1 units, 6,058 × 2,438 × 2,591 mm and 12,192 × 2,438 × 2,591 mm, which are also the sizes published on our product page.
ISO 1496-1, Series 1 freight containers — Specification and testing — Part 1: General cargo containers for general purposes: the specification and test regime a general-cargo box is built and type-tested against, which is what a converted unit starts from.
ISO 1161, Series 1 freight containers — Corner fittings — Specification: the corner fittings through which lifting, stacking and securing loads enter, and the reason they are not cut during a conversion.
International Convention for Safe Containers (CSC), 1972, adopted jointly by IMO and ILO, including the safety approval plate and the Approved Continuous Examination Programme: the transport-safety regime, which is not an occupancy approval.
EN 1993-1-1, Eurocode 3: Design of steel structures — General rules and rules for buildings: the basis for designing the framed openings and reinforcement a conversion needs.
ISO 12944-2, Corrosion protection of steel structures by protective paint systems — Classification of environments: the corrosivity categories (C1 to CX) used to state what a coating has to survive on a given site.
EN 13501-1, Fire classification of construction products and building elements — Classification using data from reaction to fire tests: the A1 to F classes, with the s1 to s3 smoke and d0 to d2 droplet additional classes, that a panel core is classified under.
ASTM A123/A123M, Standard Specification for Zinc (Hot-Dip Galvanized) Coatings on Iron and Steel Products: the coating specification for the galvanised steel frame.
Unit sizes, panel options and loading counts (four sets per 20 ft, eight sets per 40 HQ) are the published figures on our detachable container house page; plan areas on this page are arithmetic on those envelope dimensions.

Standards are cited for the definitions and requirements they contain. Prices, lead times, minimum order quantities and loading for a specific order are quoted per project against the drawing and the destination.