Every flatbed truck is different. Deck heights vary, cross-member spacing differs, and tie-down configurations are rarely the same from one build to the next. That's why we designed our flatbed enclosures with flexibility at the core — rather than dictating a single mounting approach, we've engineered the shell to support four distinct methods, each with its own trade-offs in labour, thermal performance, and hardware.
Before we walk through each option, one important note: our enclosures ship as structural shells, not finished campers. Outfitting, windows, and final mounting hardware are all part of your build process. This gives you maximum freedom to tailor the installation to your specific rig — but it also means the mounting solution is ultimately your responsibility.
Whatever method you choose, please take the time to engineer it properly. These enclosures travel down the highway at speed, and your safety depends on a solid attachment.
The Foundation: A Load-Bearing Composite Floor
What makes all four mounting methods possible is the floor itself. Our flatbed enclosure floors are flat, stiff, and structurally load-bearing — engineered with the same composite construction philosophy we apply to our full expedition truck cabins. This floor can accept bolts, brackets, and point loads without deflection, provided hardware is placed in alignment with the internal floor structure (more on that below).
Method 1 — Embedded Floor Steel with Drilled and Tapped Inserts
Best for: Builders who want a clean, permanent, thermally efficient installation and are willing to invest the labour.
On request, we can embed 1/4" flat steel plates within the floor panel at 2-foot intervals. These steel inserts allow you to drill up from underneath your flatbed and tap directly into the floor — no through-holes, no exposed fasteners on the deck surface.
We recommend 3/8" Grade 10 bolts for this application.
Why it's not the default: Steel inserts add weight, and many customers don't need them. Because of this, they are not included automatically — you must request them at the time of ordering.
The thermal advantage: This is the only method that avoids any direct metal-to-metal contact between the enclosure floor and the flatbed deck. If thermal bridging and interior condensation are concerns for your build, this is the method to consider.
Method 2 — Through-Bolting the Floor Panel to the Deck
Best for: Most builders. This is our most popular mounting method for good reason — it's straightforward, reliable, and requires no special order configuration.
Through-bolts pass vertically from inside the enclosure, down through the composite floor, and through the flatbed deck material below. On the underside of the flatbed, large fender washers or steel baseplates distribute the clamping load across the deck surface, preventing pull-through under dynamic loads.
Critical alignment requirement: Bolts must be placed in line with the internal floor structure — the ribs and framing within the composite panel. Bolts placed in the foam core zone will compress the core over time. If you're unsure of the internal layout, contact us before drilling and we'll point you in the right direction.
This method does create direct contact between metal fasteners and both the enclosure floor and the deck, which introduces a small degree of thermal bridging. For most use cases in a well-insulated camper build, this is a practical trade-off.
Method 3 — Sidewall Steel Plate Brackets
Best for: Builders who want a robust, user-friendly attachment that ties the enclosure to the flatbed along its full length, rather than relying on floor penetrations.
We embed flat steel continuously along the bottom edge of both sidewalls, running the full length of the enclosure. You fabricate custom steel brackets that bolt to this embedded steel on one side and clamp or bolt to your flatbed structure on the other — effectively wrapping the lower edge of the enclosure to the deck.
Please reach out to us directly for specific guidance and bracket design instructions before fabricating. Because every flatbed is configured differently, the brackets themselves are not included with the enclosure — you'll need to design and build them to suit your truck.
This method distributes load well and keeps the floor panel free of penetrations.
Method 4 — Corner Cradling Brackets
Best for: Builds where the flatbed corner geometry lends itself to fabricated corner brackets, or where a clean exterior appearance is a priority.
Custom brackets are fabricated to cradle or overlap each of the four enclosure corners, then bolted down to the corners of the flatbed deck using Grade 10 fasteners. This method transfers load through the corners rather than the floor or sidewalls.
A practical detail here: each corner of the enclosure includes a jack mount point, which has a 1/4" steel backing plate already laminated into the panel. These backing plates give your corner brackets a solid anchor point. Contact us directly for the exact location of these mounts before laying out your bracket design.
Choosing the Right Method for Your Build
There is no universally correct answer — the right method depends on your flatbed's construction, your fabrication capabilities, and your priorities around weight, thermal performance, and labour.
A few questions worth thinking through before you start:
- Does your flatbed have accessible cross-members that align well with through-bolts or floor inserts?
- Is weight a critical factor? Method 1 adds steel; Methods 3 and 4 require fabricated brackets that also add mass.
- Do you have welding or metal fabrication capability, or access to a shop? Methods 3 and 4 benefit from it.
- Is thermal efficiency a priority for your climate and intended use? Method 1 is the standout here.
In some cases, none of the four methods will map cleanly to a particular flatbed configuration. That's expected — custom builds sometimes require custom solutions. What matters most is that the final installation is mechanically sound, load-rated for highway travel, and designed with the right fastener hardware throughout.
If you have questions about any of these methods or want guidance specific to your truck and flatbed setup, don't hesitate to reach out to our team. We're happy to look at photos of your build and offer practical advice before you start drilling.
Drive safe. Build well.