Lofty aspirations? Beware the pitfalls of extending into the attic!

Robert Hamilton explains the ins and outs of Permitted Development regulations

"My friend’s builder says he can make me a room up in the loft space with no need for planning permission because it is Permitted Development. Is that true?"

Permitted development is becoming something of a thorny topic. All too frequently I survey a property where the proud owner has extended up into the roof space and happily says ‘well, it is Permitted Development’ and I have to break some bad news. Whilst you have a nice big attic and think it would be really useful to make another bedroom up there, perhaps with an en-suite and a couple of Velux windows, just steady on there!  

Unfortunately, often this term just isn’t correctly understood. Yes, you can create up to an additional 50m³ of space (40m³ in a terrace) and whilst there are various restrictions about size and position most small projects are permissible. However, and this is a big however, whatever you do must still comply with other regulations. 

Your first consideration is to check whether you are in a Conservation Area and / or whether your property is Listed.  

There are now about 10,000 Conservation Areas in the UK. ‘Their purpose is to protect and enhance areas of special architectural or historic interest and place additional development control on new works, as well as seeking to minimise the loss of the existing built and natural environment’. Cotswold District has the highest number - 144 - of any district council in the UK.

Even if you are in a Conservation Area or Listed this is not to say that a contemporary style is vetoed - just look at the new Gloucester Services on the M5, which has been recognised as the best of modern eco-friendly design by gaining awards from the RIBA (Royal Institute of British Architects) and the CPRE (Campaign to Protect Rural England) amongst a host of others. 

However, with a small project it is sensible to keep your expectations similarly small or you can set up a whole host of problems that render that simple little idea a massive burden. And if you think you can ‘get off’ with a fine or even ‘get away with it’, don’t even contemplate doing so. Should you wish to sell the house you will find your illegal work will cause a big problem for the potential purchaser…who may rapidly become an ex-purchaser!

Then there are Building Regulations and Fire Regulations - compulsory technical requirements that all building works must meet. All alterations fall into this category, with or without separate planning permission.

Before you start work you must establish whether the floor joists or roof trusses support what you intend to do. Many modern (and not so modern) constructions have quite lightweight timbers in the attic that are not load-bearing. It is quite upsetting to create a lovely room only to find half the furniture trying to exit through the floor! 

You must also check whether you can create the minimum headroom of two metres in the centre of a flight of stairs, with an opening window of at least 0.33m² to allow for escape in the event of fire. All electrical installations must be carried out by a qualified, certified electrician and of course minimum standards apply for thermal insulation of walls, floors and roof (although with modern materials this is much less onerous than it would once have been).

Under Fire Regulations you must also have minimum 30 minutes’ fire resistance for all floors, doors and stairs to the attic conversion.

So remember the golden rules! Even if you fall outside the Conservation Area and your property is not listed you must not make other fabrics, services and fittings less compliant than they were before or worse, dangerous. Sadly, most problems that I see are simply not making sure the structure can bear extra weight or paying inadequate attention to fireproofing. The first is plain stupid and the latter, well… unforgiveable.

Central Surveying has offices in the Cotswolds and Knightsbridge, specialising in independent professional surveying and property consultancy services for commercial and residential clients in the Cotswolds, South West and London. Robert Hamilton works from Naunton in the heart of the North Cotswolds. To contact Robert, telephone 01285 640 840 or visit