Short answer: converting a box truck into a mobile business is mostly metalwork — cutting openings into a structural aluminium body and putting the strength back around them. Serving windows, side windows, sliding doors, stairs and shelving are all normal work for us. Because the box has to be opened up and worked on properly, build-outs are shop jobs, not driveway jobs.
The part people underestimate: the box is structural
A cargo box isn't a shed on wheels. The skin, the posts and the rails work together, and every panel carries load while the truck twists over driveways and expansion joints. Cut a three-foot serving window into a side wall and you've removed a section of that structure. Done properly, the opening gets a frame that carries the load around it. Done badly, the corners of the opening start cracking within months and the panel oil-cans every time the truck flexes.
That's the difference between a build-out and a hole. It's also why we're direct about this being shop work.
What we fabricate and install
- Serving windows — framed, squared and sealed, with the surrounding structure reinforced.
- Side windows — for light, ventilation or customer-facing setups.
- Sliding doors and side doors — the usual answer when a rear roll-up alone doesn't work for how you operate.
- Stairs and steps — fabricated to the truck and the way people actually get in and out of it.
- Shelving and interior aluminium work — mounted into the structure, not screwed to the skin.
- Custom aluminium fabrication — brackets, frames, hatches, panels and the odd thing nobody makes a part for.
Several of these are visible in our work gallery: side windows for a customer launching a mobile business, a sliding door added for a conversion, and custom stairs fabricated for a fleet.
How a build-out is planned
Before anything is cut, three questions decide the layout:
- Where do people and product flow? The serving side, the prep side and the entry all want to be in sensible places relative to each other and to where you'll park.
- What's already in the walls? Posts, wiring runs, liftgate mounts and rails all constrain where an opening can go. Sometimes an opening moves six inches to land between posts.
- What does the truck need to keep doing? Load rating, door function and weight distribution don't stop mattering because the box now has a window in it.
We'd rather spend the time on that conversation than cut twice. Bring measurements, photos of the truck and a rough sketch of what you picture — even a bad sketch communicates more than a paragraph.
What the work actually involves
Broadly: mark and verify the opening against the structure inside, cut, build and fit the frame that restores the load path, fit the window, door or hatch, weld and finish the surrounding metal, then seal the whole assembly so it stays watertight while the truck flexes and bakes. Interior fittings get mounted to structure. Edges get finished so they're safe to work around every day.
What we don't do
We're straight about scope. We fabricate and install the metalwork — openings, windows, doors, stairs, shelving and structure. We are not a licensing consultant, and we're not going to tell you what your county health department will accept. Check your permitting and inspection requirements before the design is locked, because the answers can change where a window goes or how a door swings.
Buying a truck to convert
If you haven't bought yet, the metal is worth more attention than the mileage. Look at:
- The roof — leaks that have been living there a while, covered in box truck roof repair.
- The floor — soft or swollen plywood means water has been getting in for a long time.
- The corners — see corner caps.
- The panels — patches over patches, and popped rivets, in aluminum panel damage.
- The rear door — does it run smooth and stay where you leave it?
A cheap truck with a wet floor stops being cheap the moment the conversion starts, because floor and roof work has to happen first.
Sequence matters more than you'd think
Build-outs go wrong when the order is wrong. Structural repairs come before openings; openings come before interior fit-out; sealing happens once the metalwork is finished, not in between. Fitting shelving before an adjacent window is cut means moving the shelving. Sealing a window before the panel around it is finished means cutting the seal back out. We'd rather map the sequence with you up front and cut once than work around decisions made halfway through.
Keeping it running afterwards
Once a truck is earning, it can't sit. Doors, gates and seals still fail, and the same mobile service that keeps delivery fleets moving applies to a converted unit — we come to you. Arizona-specific wear is worth reading in box truck care in Arizona heat.
Start with a phone call
Call (480) 251-1521 — 24 hours a day, English or Spanish — and describe the truck and what you want it to become. See the full list of services, the work we've finished, or the shop behind it.