Loft Conversion Cost Calculator

How Much does it Cost to Convert Your Loft?

In considering on whether to convert a loft into living accommodation there are two important factors that must be examined. First, the height of the loft from floor to ridge must be at least 2.1 metres (about 7 feet) otherwise it is unlikely that permission will be granted to go ahead. Second, the question of access must be carefully considered. There must be space on the floor below to install a staircase wide enough to allow furniture to be moved into the loft.

Planning permission is not usually required but this should be checked with the local planning office. Building regulation approval is essential so an architect or a package firm of loft converters will need to be appointed. A loft conversion can add up to 20% to the value of a house and can be completed in a relatively quick time say four to six week depending upon on the size. Note that the figures produced by the calculator exclude VAT, planning and legal costs but include a simple staircase for access.

The loft conversion calculator requires you to know the floor area of the loft, the number of roof windows or dormers required, the number of storeys the existing house has, whether you require a bathroom adding and some idea of the level of finish required on the loft extension project.

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Loft Conversion Calculation Notes

The online loft conversion cost calculator above generates approximate costs of different windows choices and various sizes of loft conversions. It also weights the price based upon the geographic location the conversion is being carried out

The data is based upon input from a quantity surveyor on real loft conversions ranging in size from 20m2 to 30m2. Loft conversion projects outside of these sizes are likely to be less accurate as the data has been extrapolated.

BUT these loft conversion costs exclude:

It cannot be stressed enough the figures displayed are approximate and quotations from reputable contractors should be obtained if a decision is taken to go ahead with the building work. - Disclaimer

We hope you find this calculator on how much it costs to convert a loft helpful.