Once the total chargeable floorspace of a new build is determined, the liability charge is then calculated using Reg.40 and Schedule 1 – It is only at this point that demolished / converted floorspace is deducted from the CIL ‘liable’ floorspace (see ‘are any deductions to the GIA available’ below), leaving the CIL ‘chargeable’ floorspace.
Please see our CIL charging schedule for information on the different charge rates applied.
You can read more on applying the Schedule 1 calculation on the GOV.UK website.
Chargeable floorspace?
The RICS Code of Measuring Practice definition of Gross Internal Area is used in all instances
Chargeable floor space includes:
- areas occupied by internal walls and partitions
- areas with a headroom of less than 1.5m
- columns, piers, chimney breasts, stairwells, lift-wells, other internal projections, vertical ducts, and the like
- atria and entrance halls with clear height above, measured at base level only
- pavement vaults
- garages
- conservatories (BCIS)
- internal open sided balconies, walkways, and the like
- structural, raked or stepped floors are treated as a level floor measured horizontally
- horizontal floors with permanent access below structural, raked or stepped floors
- corridors of a permanent essential nature (eg fire corridors, smoke lobbies, etc)
- areas in the roof space intended for use with permanent access (BCIS)
- mezzanine areas intended for use with permanent access
- lift rooms, plant rooms, fuel stores, tank rooms which are housed in a covered structure of a permanent nature, whether or not above main roof level
- service accommodation such as toilets, toilet lobbies, bathrooms, showers, changing rooms, cleaners’ rooms and the like
- projection rooms
- voids over stairwells and lift shafts on upper floors
- loading bays.
Chargeable floor space excludes:
- perimeter wall thickness and external projections
- external open-sided balconies, covered ways and fire escapes
- canopies
- voids over or under structural, raked or stepped floors
- greenhouses, garden stores, fuel stores and the like in residential property
- open ground floors and the like (BCIS) i.e. terraces and parking spaces (not housed).
Deductions to the GIA
The gross internal area (GIA) of existing buildings within the chargeable development that are going to be either converted or demolished may be deducted from the total CIL liable GIA if:
- it is not greenhouses, garden stores, fuel stores and the like in residential property; and
- the building is permanent and substantial; and
- the building going to be demolished has been in continuous lawful use (meaning its lawful purpose) for 6 months or more in the last 3 years on the date of approval of the permission; or
- the existing building will continue to be used for its lawful purpose without a change of use.
Please note: Floorspace due to be demolished/converted must be standing, and contained within the red edge of the development, on the day that planning permission is approved.
Proposed converted/demolished floorspace will not be considered as eligible for deduction unless substantial evidence is submitted confirming its in-use status.
If the site has a mixture of use classes contained within its proposed development, any eligible demolished floorspace will be deducted from any new floorspace via apportionment.
What does in-use mean?
A building must be in-use for its lawful purpose - it is not sufficient that the building has a lawful use to which it could be put.
This follows the High Court judgement of, R (Hourhope Ltd) v Shropshire Council [2015] EWHC 818 Admin, which said that the building must actually be used for its lawful purpose not just that the building has a lawful use which could be carried on.
As an example, stables must be in-use as a building in which livestock (especially horses) are kept, not put to use as general storage.