What you need to know about building an extension

A home extension could provide you with that extra space you’re looking for and might even increase the overall value of your home.

Building an extension gives you extra space
and could increase your home’s value

Home extensions have become more popular in these unstable economic times, with people having to make do rather than move out. But extending your home could in fact boost its value as well as providing you with the space you crave. According to the Halifax Home Improvement Survey an extension could add, on average, nearly £26,000 onto the value of your home. With the average cost of an extension under £20,000, that’s an increase of around £5,000.

Types of extension

An extension could mean building a new one or two storey structure from scratch, but it could also mean making use of unused areas of your property. More and more people are saving money by choosing to extend into their lofts, basements and garages instead, where planning permission is not usually needed. “Eight times out of ten you don’t need planning permission for a loft conversion and they work out cheaper than a built on extension,” says Andrew Shepherd, of Shepherd and Dixon Ltd, Croydon.

Think about what you need the room for and look at existing space you might have. For instance, homes with small gardens but old dug out cellars could utilise that space. “Basement conversions are very popular at the moment, they are cheaper even than loft conversions, ” says Gary White, of Storm remedial services LTD, in Bristol.

Garage conversions and conservatories rarely need planning permission and are another cost-effective alternative to building an entirely new room. “Some people want a conservatory as a traditional room, but more people are now using it as somewhere for the kids to play or extra living space,” says Steve Carpenter of Dobsons in Hertfordshire.

Planning permission for extensions

Unless you live in a listed building or conservation area, you can normally avoid having to obtain planning permission for an extension, as long as you follow guidelines. These include making sure the extension doesn’t cover more than 50% of the garden and isn’t higher than the existing roof. You should always check with your local planning office to see whether you need to complete an application.

Alternatively, you can hire a professional surveyor, architect or project manager to advise on planning application matters. Architect Claire Haigh, of Claire Haigh Associates in Brighton, says that: “When a client contacts me, I will go and have a look at the property, discuss their requirements and look at whether they need planning permission."

You can also add space with a conservatory or
a loft, basement or garage conversion

If permission is needed than a planning application form and detailed plans will need to be drawn up, the application process takes eight weeks and costs around £150 in England. If approved, you will need to apply for building application approval to ensure your extension is built to current regulation standards.A building inspector will visit the property to ensure that the extension meets required standards and issue a completion certificate when finished.

If your extension involves construction within three meters of another house or carrying out work on shared walls, you will need to gain your neighbours permission under the Party Wall Act 1996. Once the party wall notice has been served (usually about two months before work begins) your neighbour has 14 days to agree to the project, if they don’t, then surveyors need to be brought in to mediate and draw up a solution.

Who you might need to hire for an extension

During the planning application process, hiring a quantity surveyor or architect to help can make things a lot simpler. If you’re building a large extension, you might also want a project manager on site to oversee things, especially if you can’t be on site yourself. Appointing a quantity surveyor could also be beneficial if you are working on a strict budget. “People regret not hiring a quantity surveyor when there is a dispute over why the budget has got out of control,” says William Blake, of William Blake Associates Ltd in East Sussex.

Hiring good builders, designers, decorators, electricians and other contractors will ensure that your extension meets proper legal standards and is safe and comfortable to live in. Hiring contractors who are members of trade associations like the Federation of Master Builders (FMB) will ensure you get the best results, as Brian Berry, from the FMB says: “FMB members on average carry out around 250,000 projects a year and of those, we receive less than 0.02% complaints.”

Costing an extension

The cost of your extension will vary depending on what and how you choose to expand. Conservatories, loft and basement conversions may be cheaper than a built on extension, depending on the structural work involved. You should always get at least three quotes for the project.

AB