Top tips for designing and building a garden room

Boost your living space with an outbuilding. Cheaper than an extension, a garden room may not require planning permission and can make a designer statement in your own back yard

a garden room design with large steel door

Image: Will Price 

From off-the-peg timber kits to architectural commissions, a garden room can be tailored to all budgets and functions. Read our top tips on how to plan and build your own extra living space without an extension.

Check if you need planning permission

Permitted development rules allow half of your garden to be used for outbuildings, but there are strictures around height if you site a structure close to a boundary.

If want to use an outbuilding as a self contained flat, or similar, you will need planning permission.

Building regulations apply if you use the space for sleeping, it is between 15 and 30 square metres or is a metre or less from a boundary.

Shop around for a timber kit

A timber kit is the cheapest garden room option and costs from £6,000 if you put it together yourself. Lots of kits can be customised.

Timber kit checklist

When buying look for walls at least 6cm thick, Structured Insulated Panels or SIPs, double glazing, insulated roofs and floors, EPDM rubber roof with shingles or tiles (rather than felt).

If buying a kit, you will need to budget for groundworks, insulation, electrics and paint finishes because these will not be included in the price.

Consider an architect

If you want something bespoke, individual and beautiful and you have the budget, then commission an architect to design a garden room for you.

An architect will bring innovation and a one-off design specific to you and your garden.

Lay on the services

Include heating, lighting and plug sockets if you want to use your garden room all year round.

Extend your home’s electricity circuit to the garden through cables buried in a trench. Include network cabling if you want internet access and always use a qualified electrician.

Look at the heating options

Invest in insulation rather than extending your gas central heating system. It will be too costly.

Consider an underfloor heating kit with insulation boards and a thermostat. They cost around £400 for 2.5 x 3m room. For a renewable solution, try an air source heat pump. They cost from around £1,500.

Fit out your garden room

Most garden rooms are used for home offices. If this is what you plan to use yours for, include a built-in desk and storage for a smart look.

If you lack shed space elsewhere in the garden, you might want to allow storage for bikes or gardening paraphernalia. Create a separate space for this to one side or at the back of your garden room so it is out of sight.

Discover lots more garden design inspiration at Grand Designs Live

Words: Emily Brooks, from original article on Grand Designs Magazine 

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