Insulated Garden Room / Office

A garden on a slope, with a client-supplied log cabin kit and a requirement that it end up as a genuine year-round room rather than a shed with a heater in it.

Re-levelling the garden

The existing slabs were lifted and crushed for reuse as hardcore beneath the cabin base — no reason to pay to remove material and then pay again to import its replacement.

Along the back wall, railway sleepers were installed to form a raised planter once the soil in front had been taken away.

The base

A 100 to 150mm concrete slab was shuttered and poured for the cabin to sit on. A prefabricated building is only as square and as dry as the slab beneath it — if that is out, the doors never quite close and the problem is permanent.

Making it a room rather than a shed

The cabin was erected, then upgraded well beyond kit specification. We installed 50mm PIR insulation to the walls, on top of the roof and floor insulation supplied with the kit. The interior was plasterboarded, taped, jointed and painted, so it reads as a room rather than a lined timber box.

Electrics were run out to the cabin with its own sub fuse board, sized to carry an air conditioning unit, several appliances and lighting. Sockets and decorative hanging LED lights were supplied and fitted throughout. Running a properly rated supply and its own board is what makes a garden building usable as an office — an extension lead from the house is not the same thing and never will be.

Outside

Groundworks were prepared for a 4m x 5m patio and paths linking the house to the garage and the cabin. Slabs were laid on a full bed of sharp sand and cement with a resin-based jointing compound.

Turfing, after the hard landscaping was already finished

Late in the job the client decided to turf the rest of the garden. By then the porcelain was down.

That reverses the normal order and makes the work considerably harder. The grab lorry had to load and tip across slabs laid days earlier, and the digger had to track over them to reach the ground behind. Ten tonnes of spoil went out and six tonnes of topsoil came back in, every load crossing finished paving. The edges were then dug by hand to a clean line against the slabs, because a machine bucket will not hold that tolerance against a porcelain arris.

Not one slab was chipped, scratched or cracked. Anyone can protect paving that has not been laid yet. Getting plant and muck-away across a finished porcelain terrace and leaving it as it was found is a different job, and it is the part of this project we would point at.