Four-bedroom mobile home floor plan — 20 × 6.8 m twin unit

Where the size limit puts the walls

With the width fixed, the plan has to work along its length. Two bedrooms fill one end across the whole depth; then a row of shower room, third bedroom, shower room runs along one side of the middle, with the fourth bedroom running the whole way along the other; and the far end is the kitchen and dining room with the living room behind it. Those last two are separate rooms rather than one open space, which is unusual in this group and is what stops a building this long reading as a corridor with doors off it.

The biggest room is a bedroom

Living room is the largest room on the plan at roughly 34 m² — bigger than the living room. It runs almost the full length of the middle of the building on one side, a shape that suits a bed and very little else. Almost everyone does something about it, and the tool is where you find out what.

What people change

• Splitting the long fourth bedroom into a double and a utility or study — the single most common change made to this plan
• Giving a metre of that bedroom to the living room, which sits directly against its end wall
• Opening the first bedroom into the shower room beside it, so one end of the building becomes a suite
• Removing the wall between kitchen and living room, if you would rather have one open end after all

On siting: because it is made to the mobile-home definition rather than as a fixed building, putting one on a plot is usually a caravan-siting question rather than a planning application. That still depends on the plot and on how it will be used, so check it before you commit to a size. If it has to be lived in all year, raise BS3632 early — it changes the specification more than the layout does.

The 11 doors and 13 windows on the drawing were read off a render rather than surveyed. Treat them as a starting point: on a building this long, which side gets the glazing is decided by the view and the sun on your plot, not by the plan.