Building a self-contained room outdoors can be a cost-effective and stylish way to expand your home

garden office

Image: Pod Space

Whether you need somewhere to study, work from home, practise a hobby or want to accommodate overnight guests, a garden building can be a versatile solution that will enhance your home and possibly add to its value, too.

You could opt for a bespoke self-build designed by an architect, or an off-the-peg structure may meet all your requirements at an affordable price. We've rounded up what to consider when designing and building your own garden room. 

Package deal

home office garden

Image: Garden Affairs

Garden building kits come with fixed pricing, allowing you to budget efficiently, but won’t give you the creative freedom provided by a bespoke building.

Basic log cabin kits from companies such as Dunster House are affordable and can be upgraded with insulation, doubleglazing and add-on verandas, while the exterior can be stained or painted. More expensive modular kits – try Garden2Office – offer a wider range of design choices to personalise the building plus a long list of added extras, from different cladding options and additional lighting to green roofs and interior fittings.

The slot-together assembly of these buildings allows for DIY installation for further savings. However, the levelling of the site and construction of the base is a major project in itself, requiring skill, knowledge and professional equipment.

Custom one-off design

garden pod

Image: Garden Hideouts

Bespoke options don’t need to be drastically expensive, especially if you self-build and choose materials wisely.

Designing your own garden building from scratch – or asking your architect to do so as part of a bigger build – will give you more choice in terms of the room’s size, shape, proportions and materials.

Wood, stone or brick?

sustainable garden office

Image: Office In My Garden

A sustainable, pre-treated softwood such as cedar, or a hardwood like larch, will weather to an attractive silver. Or, less expensive timber such as slow-grown spruce can be stained to suit your scheme. Try Vastern for a good selection of British-grown timbers.

For a maintenance-free finish, Marley Eternit’s fibre-cement weatherboarding mimics the look of wood, and comes in a wide range of colours. Softwood timber cladding costs from £15 per sqm; fibre-cement weatherboarding and hardwood from £40 per sqm.

If you want a sleek finish, try laminate. Trespa is a good supplier, or for composite cladding, opt for LG Hausys. Both are low maintenance options; you can expect to pay around £40 per sqm for laminate and up to £300 per sqm for composite cladding.

Metal options, such as steel, aluminium or zinc, offer a hardwearing and durable finish that suits contemporary and rustic settings. Steel costs around £40 per sqm.

Brick slips and stone tiles are low-maintenance and have modern and traditional appeal. Try Brick Slips, from £18 per sqm, and SACW Paving, from £45 per sqm.

Reclaimed bricks from salvage yards will give your build character; rendered, crisply painted blockwork will create a modern finish that looks great with timber cladding.

Fitting doors and windows

outdoor garden office

Image: IQ Glass

PVCu, timber and thermally broken aluminium frames are cost-effective.

Composite framing is more expensive but allows you to have maintenance-free metal outer frames, with timber frames inside, and double-glazing will keep the room comfortable all year round.

Ensure that window and door sizes and positions reflect how you will use the room.

What is the cost?

timber framed wooden box garden room

Image: Ben Cunliffe

Prices will vary according to size, on whether the building is modular or bespoke, the materials used, the specification of doors and windows, insulation levels, and interior finishes. Expect to pay between £800 and £1,600 per sqm.


Words: Lucy Searle

Have you embarked on a garden room self build? Tweet us any tips you have come across by tweeting us @granddesignsmag or posting a comment on our Facebook page



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