Converting a van yourself is one of the most satisfying projects you can take on, but it’s also easy to do things in the wrong order and end up ripping out finished work. This guide walks through a sensible build sequence for a UK self-build, from picking the van to getting it re-registered with the DVLA, and flags the points where rules, safety standards or insurance come into play.
Before you start: plan the finished van
The best conversions are planned on paper before a single panel comes out. Decide three things first, because they shape everything else.
- How you’ll use it. Weekends away with hook-up need far less than off-grid trips in winter. Be honest about your real use.
- How many people it needs to carry and sleep. Travelling seats need proper seatbelts, and sleeping two adults needs a bed long enough for both.
- Whether you want it recorded as a motor caravan. If you do, design the layout around what the DVLA expects to see from day one (see the final step below).
Sketch the layout to scale, marking where the bed, kitchen, storage, water tanks, battery and any gas locker will go. Keep heavy items low and between the axles.
Step 1: Choose the right van (and check the weights)
GOV.UK explains that the maximum authorised mass (MAM), also called gross vehicle weight, is the weight of the vehicle including the maximum load it can safely carry, and it’s normally shown on a plate or sticker on the vehicle (GOV.UK: vehicle weights explained). Your payload is roughly the MAM minus the van’s weight once converted.
This matters for two reasons:
- Payload shrinks as you build. The DVLA’s own guidance warns that installed equipment increases the unladen weight and decreases the payload, and that a conversion should still be able to carry a passenger in every seat, plus luggage and full water tanks, without being overloaded (GOV.UK: converting a vehicle into a motor caravan).
- Your licence may limit you. If you passed your car test on or after 1 January 1997, category B lets you drive petrol and diesel vehicles (including hybrids) up to 3,500kg MAM with up to 8 passenger seats (GOV.UK: driving licence categories). A van plated above that needs a different licence category.
Tip: when the build is finished, take the van to a public weighbridge with full fuel and water to find out where you really stand. GOV.UK has a weighbridge finder.
Step 2: Strip out and treat rust
Remove any ply lining, bulkhead (if you’re taking it out), racking and old fixings. Clean the bare metal, then deal with any surface rust before it gets hidden behind insulation for years. Pay particular attention to the floor, wheel arches and the bottom of the doors.
Step 3: Cut in windows, vents and roof fittings
Anything that involves cutting holes in the bodywork should happen before insulation and lining. That usually includes:
- side windows (or a window in the sliding door)
- a roof vent or fan
- a pop-top or high-top roof, if you’re fitting one
- holes for a diesel heater exhaust and intake, gas drop-out vents, or a hook-up inlet
Paint every cut edge to stop rust, and use the sealant the manufacturer specifies.
If you want DVLA re-registration later, windows matter. The current DVLA guidance looks for 2 or more windows on at least one side of the main body, not counting the driver and passenger door windows, and a window in the separate living-area door counts as one of them (GOV.UK).
Step 4: Run first-fix cables and pipes
Before you insulate, run the cables that will hide behind the walls and ceiling: lighting, sockets, USB points, solar cable and spare conduit. Leave slack, label both ends, and:
- size cables for the current they’ll carry and fuse them close to the battery
- protect cables where they pass through metal with grommets or conduit
- keep electrical runs away from gas pipework
If you plan to fit a gas cylinder locker, BS 7671 (the UK wiring regulations) says that where cables have to pass through a gas cylinder compartment, they must run at least 500mm above the base of the cylinders and be protected inside conduit or ducting (IET Wiring Matters). It’s easier to avoid the locker altogether at the planning stage.
Step 5: Insulate
Insulate the walls, roof, doors and, ideally, the floor. Two practical points:
- Condensation is the real enemy. Warm, moist air meeting cold metal is what causes damp and mould. Aim for good, continuous coverage and plan your ventilation (Step 9) alongside your insulation.
- Follow the product’s instructions. Some insulation materials are designed to be used with a vapour barrier, others aren’t. Check what the manufacturer recommends rather than mixing methods.
Step 6: Floor, walls and ceiling
Lay the subfloor, line the walls and ceiling with ply or lining carpet (using existing fixing points or rivnuts where possible), and fit the final floor covering before the furniture goes in.
Step 7: Build and fix the furniture
Now build the bed, kitchen unit, seating and storage, either from scratch or from a flat-pack kit. Our guide to campervan conversion kits in the UK compares what UK suppliers sell.
Everything must be rigidly fixed to the vehicle. The DVLA describes the internal features of a motor caravan as seats and a table, sleeping accommodation (which can convert from the seats), cooking facilities and storage, and says this equipment must be rigidly fixed to the living compartment, although the table may be designed to be easily removable (GOV.UK).
Any seats and seatbelts used while travelling must be securely mounted, which the DVLA guidance also stresses. Many self-builders buy a rock and roll bed or seats that the supplier states have been crash-tested, rather than fabricating their own.
Step 8: Second-fix electrics, water and gas
12V system
Fit the leisure battery, charging (engine, solar and/or hook-up), fuse box and switches, then connect the circuits you ran in Step 4. Add a battery isolator.
230V hook-up
Mains electrics in a motor caravan are covered by Section 721 of BS 7671. Among other things, the inlet must comply with BS EN 60309-1, be no more than 1.8m above the ground, be readily accessible and be rated at least IP44, and there must be a main isolator inside the van (IET Wiring Matters). Unless you’re qualified, have a competent electrician install or at least inspect and test the 230V side.
The Caravan Club’s guidance on hook-up leads says a compliant cable is a single continuous 25m (±2m) length with conductors of at least 2.5mm² and blue BS EN 60309-2 connectors (The Caravan Club).
Water
A fresh water tank, 12V pump, tap and waste container is the simple set-up. Secure tanks low down, and remember a litre of water weighs about a kilo, all of it off your payload.
Gas
The current standard for LPG in leisure vehicles is BS EN 1949:2021, alongside the Gas Safety (Installation and Use) Regulations 1998 (Vandercamp Adventures’ summary). Gas Safe Register’s own technical guidance says that anyone carrying out gas work in leisure accommodation vehicles to comply with those regulations must be Gas Safe registered for that work (Gas Safe Register Technical Bulletin 063).
In practice, many self-builders design the gas locker and layout themselves, then have a Gas Safe engineer qualified for LPG in caravans and leisure vehicles install or check and certify it. Keep the paperwork. If you’d rather avoid gas altogether, a diesel heater and an induction or portable cooker are common alternatives.
Step 9: Ventilation and safety kit
Fit fixed ventilation, especially if you’ll cook or use gas inside, plus the basics before your first night away:
- a carbon monoxide alarm
- a smoke alarm
- a fire extinguisher and fire blanket near the kitchen
- a gas alarm if you have gas on board
Step 10: Insurance, MOT and DVLA
Insurance
Tell your insurer you’re converting the van. Standard van policies may not cover a conversion in progress, and some specialist insurers offer cover during the build. Our self-build campervan insurance guide explains how it works and who offers it.
Re-registering as a motor caravan
You don’t have to change the body type to use the van as a camper. The DVLA says the vehicle can still be used for that purpose as long as you’re satisfied it meets the internal features of a motor caravan (GOV.UK).
If you do want it recorded as a motor caravan, the DVLA’s guidance updated on 20 October 2026 lists three external features: 2 or more windows on at least one side of the main body, a separate door into the living area, and a high-top or pop-top roof. You send the V5C with a completed checklist and labelled photos. Our step-by-step DVLA motor caravan re-registration guide covers the whole application.
Van conversion build order checklist
- ☐ Plan the layout and check the van’s MAM and payload
- ☐ Strip out, clean and treat rust
- ☐ Cut in windows, vents, roof and heater/gas holes
- ☐ Run first-fix cables and conduit
- ☐ Insulate walls, roof, doors and floor
- ☐ Fit subfloor, wall and ceiling lining, and floor covering
- ☐ Build and rigidly fix furniture, beds and seats
- ☐ Fit 12V system, hook-up (inspected by a competent person), water and gas (Gas Safe engineer)
- ☐ Add ventilation and alarms, fire extinguisher and blanket
- ☐ Update your insurance, weigh the van, and apply to the DVLA if you want to
FAQ
What order should I do a van conversion in?
Plan, strip and treat rust, cut holes, run first-fix cables, insulate, line, build furniture, then fit electrics, water and gas. Doing holes and cables before insulating saves undoing finished work.
Can I fit gas in my self-build campervan myself?
The installation needs to meet BS EN 1949, and Gas Safe Register’s guidance says anyone doing gas work in leisure vehicles under the gas safety regulations must be registered for it. The safest route is a registered engineer qualified for LPG in leisure vehicles.
Do I need an electrician for campervan electrics?
The 230V hook-up side falls under BS 7671 Section 721 and should be installed or tested by a competent electrician. Many people fit the 12V side themselves.
Will my conversion take me over 3,500kg?
It might. Check the MAM on the plate and weigh the finished van with full fuel and water.
Do I have to re-register my van as a motor caravan?
No. The DVLA says you can use it as a motor caravan without changing the body type, as long as it meets the internal features.