Garden Room Costs in Barnet & North London: An Honest 2026 Price Guide

A garden room is one of the biggest outdoor projects you can take on, and online prices range from a few thousand pounds for a kit to well over £50,000. Here is what a properly built, insulated garden room really costs in Barnet, Enfield and North London, based on the rooms our own team builds.

How much does a garden room cost?

Most of the garden rooms we build cost between £22,000 and £32,000. Where your room sits in that range depends mainly on its size, the finish you choose and what is needed underneath and around it. Larger rooms, or rooms with a toilet or shower, cost more.

For comparison, independent UK price guides in 2026 put a professionally built, insulated garden room at roughly £1,400 to £3,000 per square metre, with London usually at the higher end. Cheap kits and log cabins cost far less, but they are not insulated or finished to the same standard and still need a base, electrics and fitting.

What changes the price

• Size. The bigger the room, the higher the total, although the cost per square metre usually drops as rooms get larger.

• Base and groundwork. Sloping gardens, clay soil, tree roots or difficult access all add work before the room goes up.

• Insulation and glazing. Year-round use needs proper insulation in the floor, walls and roof, and good-quality doors and windows.

• Cladding and finish. Cedar, composite or painted finishes all look different and cost different amounts.

• Electrics. Lighting, sockets, heating and the cable run from the house.

• Plumbing. A toilet, sink or shower adds drainage and water supply, and is the biggest single extra.

• Decking and landscaping. A deck, path, patio or planting around the room makes it feel finished and connected to the garden.

What to check in any garden room quote

• Is it a full build or just the shell? Ask exactly what is included: base, insulation, electrics, interior finish, decking.

• What type of base is used and how deep it goes.

• Who does the electrical work and whether it will be certified.

• Is VAT included?

• What guarantee comes with the structure and the workmanship?

Do you need planning permission?

Many garden rooms are built under permitted development, so no planning application is needed. As a general guide the room should be single storey, no more than 2.5 metres high if it is within 2 metres of a boundary, cover no more than half of the garden, and not be used as a bedroom. Rules are different for listed buildings, conservation areas and flats, and rooms over 15 square metres can need building regulations approval. Always check with your council, Barnet or Enfield, before you commit. We talk this through at the first visit.

Why build with Verdant Vision Pro

We have been building in Barnet and North London since 2009. Because we also do patios, decking, fencing and lighting, we can build the room and finish the garden around it in one project, with one team. See more on our garden rooms page, or read how to choose a landscaper.

Every job starts with a free home visit, a free 3D design and a clear written quote. There is no upfront deposit, you pay in stages, our own team does the work with no subcontractors, we are fully insured and we give a 5-year workmanship warranty. Call 07903 915535 or send us your details.