WhatHut › Garden offices, insulation and building regulations

Garden offices, insulation and building regulations

A garden office is a room, not a shed. That changes the build quality, the insulation, the electrics and sometimes the rules you need to follow.

Last updated 2 November 2026

What makes a garden office different

A garden office is built to be used for hours at a time, year round. That means insulation in the walls, floor and roof, double glazing, heating or cooling, power and data, and good ventilation to avoid condensation. A basic shed with a desk in it will be cold and damp in winter and hot in summer.

Insulation

Insulation turns a timber box into a room. Common approaches include insulating between and under the frame, using insulated panels, or building with structural insulated panels. Thicker tongue and groove walls help, as one supplier guide notes 11 mm to 15 mm boards are best for insulation of the common wooden cladding types, but cladding alone is not insulation. Plan for a vapour control layer and ventilation so moisture doesn't get trapped. A good installer will explain the build-up they use and the thermal performance they claim; ask for it in writing.

Power, lighting and heating

Electrics in a garden building must be safe. Fixed electrical work in a garden building has its own safety and notification rules, so use a registered electrician who can certify the work. We have not checked the current regulations, so ask your electrician or building control what applies to your build. Plan the cable route before you build the base, and use armoured cable or ducting as advised. Heating options include electric panel heaters or a small heat pump; avoid anything that creates fumes without proper ventilation.

Building regulations

The Planning Portal states that planning permission and building regulations are different, and links to a separate page on building regulations for outbuildings. In general, small detached single-storey buildings used as storage or a place to sit may be exempt from building regulations, but exemptions depend on floor area, distance from a boundary, materials and use. Sleeping accommodation or a building attached to the house changes things. We didn't confirm the current floor area thresholds, so check the Planning Portal's building regulations page for outbuildings, or ask your local building control, before you order.

Planning and use

As with any outbuilding, the permitted development limits apply: single storey, eaves up to 2.5 metres, overall height up to 4 metres (dual-pitched) or 3 metres, and tighter limits near boundaries and on designated land. The Planning Portal adds that the rules don't cover a change of use or separate self-contained living accommodation. Using a building as an office, hobby space or gym is incidental to the home; using it as a separate dwelling, a business with visitors or an Airbnb may need permission. See planning permission.

Shepherd's huts

A shepherd's hut is a hut on wheels with a curved or pitched roof. It can be fully insulated, with a stove and a bed. Whether it counts as a building or something else for planning depends on how it is used and fixed; ask your local planning authority. If you plan to sleep or let it, check planning, insurance and any licensing. Wheels do not exempt it from the rules by themselves.

Base and access

Garden rooms are heavy, so use a robust base: see bases. Plan delivery access too. Many large buildings arrive in panels or on a lorry, and gate width and side access matter.

Checklist before you order

1. Check planning limits and designated land.
2. Check building regulations with building control.
3. Plan the electricity supply and use a registered electrician.
4. Ask the supplier for insulation details, warranty and what's included.
5. Budget for the base, groundworks, electrics and finishing. See prices.
6. Tell your home and contents insurer, and check cover for contents and business equipment.

This is general information, not legal or planning advice. Rules differ between England, Scotland, Wales and Northern Ireland, and for your own property, so check with your local planning authority.

Spotted a mistake or have a question? Get in touch.