Be a convert

Check your attic is suitable Not every attic is worth converting. If it is too low in the middle or the pitch too steep, you will be unable to create a decent-sized room without lowering the ceilings of the rooms below - which will cost a lot. Building regulations stipulate minimum headroom of 2.3 metres under the apex and 2 metres over the stairs.

Decide if you want to convert the existing space or extend You can convert existing space of up to 50 cubic metres for a detached or semi or 40 for a terraced property, but if you alter the roof line or change the external appearance of your home (by adding a mansard or dormer window, for example), you need planning permission. Building control will also be involved.

Talk to your neighbours Work affecting any wall, floor or ceiling of an adjoining property will require a party-wall agreement

Calculate the costs A basic fit-out, including a bedroom and shower room, should cost £30,000-£40,000. Set aside about 15% more to cover unforeseen expenditure.

Find the right people for the job An architect or loft company will manage the whole process, from planning and design to selecting a builder. The Federation of Master Builders advises obtaining at least three quotes before starting work. And don’t rely on the cheapest - get a potential builder to provide a schedule of work. A basic conversion should take 4-6 weeks.

Think about going green Converting your loft is the perfect opportunity to add solar panels and improve your insulation.

Don’t try a covert conversion Nosy neighbours are sure to notice - and you’ll need a completion certificate for the work from a building-control officer when you sell the house.

Who else do you need to tell? Keep your mortgage lender and insurer informed, as a conversion could affect your premium.

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