Check your loft/attic is suitable
Not every loft 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 be an expensive process. In order to comply with building regulations, the loft has to be a minimum of 2.3m or 7’6″ at it’s highest point (i.e. the apex of the roof). These measurements are taken from the top surface of the ceiling boards below, to the felt at the very apex of the roof. With that in mind, we can make the most of even the smallest lofts with the imaginative use of dormer windows and staircase positioning.
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-detached property and 40 cubic metres for a terraced property without the need for planning permission. However, if you change the roofline or alter the external appearance of your home (by adding a mansard or dormer window, for example), you will need planning permission. Building Control will also be involved.
Talk to your neighbours.
Work effecting any wall, floor or ceiling of an adjoining property will require a party-wall agreement.
Find the right people for the job.
An architect or loft company (such as ourselves) 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 to 6 weeks.
Calculate the costs.
This is an open ended question however, as a rough guide a basic Dormer conversion can start at £18000 and a Velux conversion as little as £14000 but prices will vary according to size and design. However, it is always a good idea to set aside about 15% extra to cover unforeseen expenditure.
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!
Nosey 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. You will also need to keep your mortgage lender and insurer informed, as a conversion could affect your premium. Not telling them might even invalidate your insurance policy.