Modify
Container modifications & conversions
This is where containers get interesting. Our qualified engineer cuts, welds, insulates and wires containers into offices, sleepouts, tiny homes, garages and pools — all in our Napier yard, all electrically certified, all delivered finished.
The builds
Portable offices
20ft office fit-out from ~$8,500 + container. Hire options available for site offices.
See details, pricing & FAQs →
Sleepouts
20ft sleepout builds from ~$14,500 + container. High cube recommended.
See details, pricing & FAQs → Tiny homes
Complete tiny home builds priced per design — typically from the $50,000s ex GST.
See details, pricing & FAQs →
Container garages
Garage fit-out from ~$6,200 + container. Twin 20ft joined builds quoted per project.
See details, pricing & FAQs →
Plunge pools
Pool conversions from ~$18,900 fit-out + container. Each build quoted individually.
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Cafés, shops & pop-ups
Servery + retail fit-outs quoted per build — typically from the low $20,000s + container.
See details, pricing & FAQs →Or price it yourself, right now
The Build Your Own configurator uses our real price list — pick a size, purpose, doors, windows and extras, and watch the estimate update live.
Engineered, not improvised
Cutting a hole in a container changes its structure — done wrong, walls flex, doors bind and leaks start. Every opening we make is framed and reinforced by a qualified engineer with years of container work behind him. It's the difference between a conversion that works for decades and a cheap job you fight forever.
Electrical work is never DIY: our offices, sleepouts and homes are wired by certified electricians and inspected, with compliance certificates supplied. Insurance companies and councils ask for that paperwork — you'll have it.
Modification price list
- Personnel door (steel)$2,200
- Roller door$2,750
- Ranch slider$3,850
- Window$1,850
- Security bars (per window)$350
- Certified electrical (from, 20ft)$2,300
- Insulation + poly lining (from, 20ft)$6,000
- Timber deck + steps$2,800
- Cantilevered shade awning$3,400
- Custom paint (from, 20ft)$950
- Lockbox — supply & fit$195
- Lockbox padlock (each)$70
- Roof vent (whirlybird) — supply & fit$395
All indicative estimates, +GST — contact the office on 06 835 3010 for an exact quote. Area-priced items scale with container size — the configurator does this maths for you. End doors can also be added to or removed from any container — ask when you get your quote.
Modifications — common questions
What modifications can you do to a shipping container? +
Personnel doors, roller doors, ranch sliders, windows and security bars; insulation and poly panel lining; certified electrical with lighting, outlets and heat pumps; decks, awnings, custom paint and signwriting; plus full conversions — offices, sleepouts, tiny homes, garages and plunge pools. We can also add cargo doors to the blank end of a container, or remove and seal the existing end doors, depending on how you want to load it.
Who does the modification work? +
Our qualified engineer, in our Napier yard — cuts, framing and welds are engineered work, not angle-grinder specials. All electrical is installed and inspected by certified electricians with compliance documentation supplied.
How long do container modifications take? +
Simple jobs (a man door, a window) can turn around in days. Full fit-outs like offices and sleepouts typically run 3–6 weeks depending on spec and the current queue. Tiny homes are quoted with their own timeline.
Can I supply my own container for modification? +
Yes — we modify customer containers as well as our own stock. We'll inspect it first; a sound shell matters more than a pretty one.
How much do container modifications cost? +
Real numbers from our current price list: personnel door $2,200, roller door $2,750, window $1,850, insulation + lining from $6,000 (20ft), certified power from $2,300. The Build Your Own configurator totals your exact combination live.
Tell us what you're picturing
Sketch on a napkin, a Pinterest screenshot, or just an idea — we'll tell you what it costs and how it'd be built.