An insulated room for working from home, on a proper base with power run to it on its own circuit. No water needed, which keeps the job simple and the running cost of the room down.
A toilet or sink brings in drainage, usually a run back to the foul drain or a soakaway. It is a bigger job than the box itself, and the part that catches people out pricing against a brochure.
Ground conditions decide the base, not preference. Clay shrinks and swells with the seasons, and where trees are nearby, root activity can pull enough moisture out of the ground to move a shallow base within a year or two. We dig trial holes, check what we are building on, and specify a strip foundation, a concrete raft or a screw pile system depending on the soil and any trees nearby. Screw piles are often quickest, since there is no concrete to cure. A supplier fitting slabs on hardcore is not solving the same problem, and it shows within a couple of winters.
Used through the evening and weekends, so insulation and a decent heat source matter more than for a shed you visit twice a year. Cheap garden rooms are often not genuinely warm in a Suffolk January.
Once someone intends to sleep in it, the planning and building regulations position changes. We tell you plainly when a project has crossed that line, before you commit to a design.
Every garden room job starts with the ground, not the timber. We check the soil type, look for tree roots within influencing distance, and work out whether a strip foundation, a concrete raft or a screw pile base suits that spot. Screw piles suit most gardens well, going in without the mess or curing time of concrete, though heavier structures or awkward ground sometimes need a proper poured foundation instead. Getting this wrong is the biggest cause of doors that stick, floors that dip and cladding that opens up within a couple of years, and it is the step a cabin supplier has least interest in getting right.
A garden room needs its own circuit run from the consumer unit, not an extension lead trailed out the back door. That means an armoured cable buried at the correct depth, protected where it crosses a path or driveway, and terminated properly at both ends. This is notifiable electrical work under Part P, so it has to be tested and a certificate issued once it is done. A room used as an office or a gym also needs enough sockets and lighting capacity to be genuinely usable, worth planning before the cable goes in the ground.
A garden office with no water is straightforward. Add a toilet, a shower or a kitchenette and you need a drainage run, usually falling back to the existing foul drain at the right gradient, or a soakaway where a gravity connection is not practical. That means digging across the garden, working around existing services and any tree roots, and getting the pipe run right first time, since re-digging a finished garden to fix a mistake is expensive and unpopular with whoever has just planted it.
A lot of budget garden rooms use a thin insulation layer that copes with an English autumn and struggles by January. We build the floor, walls and roof to hold heat properly, and size the heating to suit. Cladding and roof choices, whether timber, render or tiles to match the main house, are as much about the room belonging in the garden as they are about weatherproofing. We talk through what suits your house rather than defaulting to whatever is quickest to order.