Case Study: A Garden Office Build in Fareham

Fareham sits in that busy stretch between Southampton and Portsmouth where a huge number of people now split the week between home and the office. Back in the spring we built a garden office for exactly that kind of client: a project manager in Locks Heath who'd spent four years working off the kitchen table and had finally had enough. Here's how the job went, what it cost, and what we'd tell anyone in Fareham weighing up the same move.

The headline numbers first, because that's what most people scroll for: 14 square metres, three and a half weeks on site, and a final bill of £27,500 all in, including power, data and decoration. The rest of this post explains where that money went.

The brief: a proper office, not a posh shed

Our client works in IT and spends most of the day on video calls, so the brief was blunt: a room warm enough to use in January, quiet enough to take calls in, and solid enough that nobody on the other end of a Teams meeting would guess he was sitting at the bottom of the garden. That ruled out anything off the shelf. Sheds and summerhouses have their place, but single-skin timber with no insulation is a three-season building at best, and January in Hampshire is not one of those seasons.

We settled on a 3.5m by 4m insulated timber building, kept deliberately under 2.5m tall so it could sit within 2m of the rear boundary with no planning application needed. Most of the garden offices, gyms and studios we build across Dorset and Hampshire fall under permitted development the same way. The usual caveats apply: if you're in a conservation area, in parts of Titchfield for instance, or the building would take up more than half the garden, check with Fareham Borough Council first. We handle that check as part of our survey.

Groundworks: one dig, two jobs

The garden sloped about 300mm across the footprint, which is typical of plots on the northern side of Fareham. We dug out and poured a reinforced concrete pad rather than using ground screws, partly because of the slope and partly because the clay round here holds water all winter and we wanted a base that will never move. The pad took two days including the dig, then sat curing for a week while we got materials on site.

While the digger was there we also cut the cable trench up to the house, 600mm deep with the armoured cable bedded in sand and marker tape laid above it. Doing both digs in one visit saved the client roughly a day's labour and meant the lawn only had to be put back together once.

The build: frame, insulation and cladding

The structure itself is a 100mm insulated timber frame with PIR board in the floor, walls and roof, a breathable membrane, and composite cladding outside that will never need painting. The roof is a single sheet of EPDM rubber, which on a building this size goes down in a morning and carries a 20-year guarantee. Full-height anthracite glazed doors face back up the garden, so the room gets afternoon light without the client staring straight into his own kitchen window all day.

Frame to watertight took five working days, which matters in a Hampshire spring, and the remaining two weeks went on first fix, insulation, plasterboard, flooring and decoration. We didn't need access to the house beyond the consumer unit, so the client kept working right through the build.

Power, data and heating

A garden office lives or dies by its electrics. This one has an 18m armoured cable run off the house consumer unit feeding a small consumer unit in the office itself, six double sockets, LED panel lighting, a dedicated circuit for a slimline panel heater, and a CAT6 data cable so video calls run on wired internet rather than whatever Wi-Fi reaches the end of the garden. Everything is installed and certified by our own electricians rather than a subcontractor we've never met, and you get the paperwork for it, which matters when you come to sell.

On heating: an insulated building this size needs very little. The panel heater brings the room up to temperature in about 20 minutes on a winter morning, and running costs have been pennies rather than pounds per day. Some clients ask about electric underfloor heating instead, which we fit too. It's a nicer heat, but it adds to the build cost, so it comes down to budget and preference.

What it cost, line by line

Every figure below is what the client actually paid this year, not a trade cost with the awkward bits missing:

• Groundworks, concrete base and cable trench: £3,400

• Timber frame, PIR insulation, cladding and EPDM roof: £13,900

• Full-height glazed doors and window: £4,300

• Electrics, including the 18m run, lighting, sockets and CAT6: £2,400

• Internal lining, flooring and decoration: £2,700

• Heating and controls: £800

That's £27,500 for 14 square metres, which works out just under £2,000 per square metre. Across the jobs we price, a properly insulated, year-round garden office in 2026 lands between roughly £1,450 and £3,000 per square metre depending on size, glazing, spec and how far the power has to travel. Long cable runs, tight access and high-end glazing are the three things that push a quote up fastest, which is exactly why we always survey before quoting rather than pricing off a photo.

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Thinking about one in Fareham?

We build garden offices, gyms and studios across Fareham, Titchfield, Stubbington, Whiteley, Portchester and the wider Solent area, alongside the rest of our work across Dorset and Hampshire. If you want honest numbers for your own garden rather than a brochure price, book a free site visit and we'll measure up, talk through the options and give you a fixed written quote.