How to Add an Extra Room

Pick up some great tips and advice on How to Add an Extra Room to your home from the organisers of the Homebuilding & Renovating Show.

Despite the current financial climate, new babies arrive, children grow up and people decide to work from home – all of which put pressure on living space. With a falling housing market, mortgage rationing and uncertain economic conditions, making the most of the space you’ve got may well be your best option. 

If you make the right improvements, you will add value – even if house prices overall are flat or falling. Long term, it will undoubtedly make your house easier to sell. 

Should You Move or Improve?

With so few buyers in the market and the number of houses available dwindling fast, improving may be the only way to meet your accommodation needs. Concerned about how much value improvements will add? Get a local estate agent in for a valuation and discuss equivalent recent sales. And don’t forget to add in agent’s fees, stamp duty and mortgage arrangement fees when doing your sums.

Planning & Building Regulations Compliance

The new planning rules that came into force last October, mean a lot of remodelling and conversion work won’t require planning approval. The permitted development rights have been relaxed so that, subject to certain design constraints and conditions, you may well find that your extension or loft conversion won’t require planning permission. However, always check with your local authority first as your permitted development rights may have been used up, restricted or removed altogether. Building regulations apply to almost all new building work and alterations. For expert guidance, go to www.planningportal.gov.uk.  

Ground Floor or Two Storey Extension

Rear and side extensions are the usually the best place to extend your home. The size will be dictated by available garden space and what is known as the 45 degree rule – an imaginary line drawn from your neighbour’s windows at 45 degrees beyond which you usually can’t extend. Foundations and roofing are the costliest elements so it’s usually more cost-effective to build over two storeys than one. For a simple two-storey brick and block extension with off-the-shelf joinery look to pay between £950 and £1150 per m2.

Adding or Removing Walls

This is the most cost-effective way to create extra room. Recycle space by subdividing existing rooms or converting ‘wasted’ space such as a loft, garage or cellar. Start by producing accurate scale floor plans so that you can see how space is currently used and identify potential. Any wall can be removed but non-load bearing are easier and cheaper to alter. Removing a 3m load bearing wall to link two rooms would cost between £2,000 and £3,000.

Garage Conversion

An attached single garage can be converted to create a good-sized room suitable for many uses. There is enough room from a single garage to create a new kitchen plus utility or a downstairs cloakroom. The structure and insulation must be upgraded to comply with building regulations but typically the floor in a garage is at least 150mm below the finished floor in the house leaving enough space to add insulation and damp-proofing. To convert an existing garage costs between £750 and £1200 per m2.

Cellar Conversion

An old basement or coal bunker can be turned into a well-located extra living room accessed from the hallway. The key tasks here are achieving adequate headroom and making sure space is light, warm, dry and well ventilated. Digging out a new basement is the most expensive way to add space but for some terraced houses this is the only option. The cost of converting an existing cellar is £750-£1,200 per m2.

Loft Conversion

This is the most cost-effective way to add an extra room. Houses and bungalows built before the 1960’s typically have a timber roof structure which lends itself to this conversion. Start with a floor plan showing how much of the loft space has clear headroom of 2.3 metres or more – this is the area where you’ll be able to stand up once you’ve upgraded the space. Don’t forget you can enlarge a loft space with dormer windows or by changing to a mansard roof. An important consideration is the stairs – they must land at a point in the attic with at least 1.9m of headroom and it will take up existing room below so consider this loss carefully. The cost of converting an existing roof space is between £600 and £1,200 per m2.

Adding a Conservatory

One of the simplest, quickest and most popular routes, with heating and ventilation a conservatory can be used all year round. If the structure is only partially glazed, it can be designed as an extension to an existing room. If fully glazed, it must be separated from the rest of the house by external doors and have its own heating. Some conservatories are exempt from building regulations but the most important thing is to decide what you want to use the conservatory for. Using your conservatory for an open-plan kitchen/diner will certainly be a more expensive option but it will free up precious space in the house.

Do your Homework

Draw up some basic plans and visit your local authority for general advice. Look on the Government’s planning website www.planningportal.gov.uk for guidance. Read magazines like Real Homes or Homebuilding & Renovating for inspiration (www.homebuilding.co.uk).