DIY with Nick Knowles: Loft conversions

Nick Knowles: What are the basics required for converting a loft?
Jeremy Wedge:
First, you need a minimum headroom of 2.3m – anything lower isn’t suitable – then look at the roof construction.

You also need to consider access. It can be possible to extend the existing staircase up into a loft, however in a bungalow you'll have to consider losing floor space. With recent laws relaxed, planning permission isn't always needed, but it's essential to check beforehand. If you plan to add dormers however, you may need local authority permission.

Nick: What is the best way to apply for planning permission?
Jeremy: You can apply for it yourself or your builder or architect can do
it on your behalf. They'll be familiar with the questions that will be asked as well as knowing what information to supply. It can be hard to get planning permission if local authorities don't have the questions answered in the right manner. Planning guidelines are open to interpretation, so it's best to ask an expert to make the application for you and get it approved first time.

Nick: Is it necessary to hire an architect?
Jeremy: Not always; architects will come into their own if you live in a listed building or if your plans are a little controversial, as they'd be in a better position to negotiate with the planners.

If you're simply converting a roof space, then you don't need an architect. Your builder will be able to advise on basic spatial requirements for things like a staircase.

Nick: Roughly how much will a loft conversion cost?
Jeremy: It depends on the space you're converting, but the average is about £10,000 to £15,000 for a small conversion, rising to between £20,000 and £30,000, depending on the complexity of the job. Remodelling the roof or any structural work like adding dormers will push the cost up considerably.

Nick: Are there any safety requirements to follow?
Jeremy: If you have a two-storey house and you add another level, you need to install a secondary means of escape in case there is a fire on the ground floor. Building regulations require that you plan extras, like fire escapes and self-closing doors. So, while you may pass the planning permission requirements, your plans will have to still pass the building regulations. Bear in mind that some loft conversions may require remodelling of the ground floor for a fire escape.

Nick: How long will a conversion take to complete?
Jeremy: If you have a professional working on it, it could take anything from
four weeks to three months to finish, depending on the job.

Nick: Are skylights better than dormer windows?
Jeremy: Skylights are a better option for letting more light in, while dormers add character to a loft space – it's really a personal choice.

About Jeremy Wedge:
Jeremy Wedge MIstrutE, CEng, is an independent chartered structural engineer and member of www.loft-conversion-uk.com.