CIL liability is based on the “chargeable area” which is calculated using the formulas set out in Regulation 40 of the CIL Regulations (2010). These require the measurement of the Gross Internal Area (GIA) floorspace of the proposed development and the GIA floorspace of any existing ‘in-use’ buildings to be demolished.
An 'in-use' building is, in a nutshell, one in ‘lawful use’ for at least 6 months of the last 3 years.
GIA is, in simplified terms, the internal floor area of the walls at each floor and includes*:
The following are excluded from CIL liable floorspace*:
An 'in-use' building is, in a nutshell, one in ‘lawful use’ for at least 6 months of the last 3 years.
GIA is, in simplified terms, the internal floor area of the walls at each floor and includes*:
- Areas occupied by internal walls and partitions;
- Columns, piers, chimney breasts, stairwells, lift-wells, other internal projections, vertical ducts;
- Atria and entrance halls, with clear height above, measured at base level only;
- Internal open-sided balconies, walkways;
- Structural, raked or stepped floors are to be treated as a level floor measured horizontally;
- Corridors of a permanent essential nature (e.g. fire corridors, smoke lobbies);
- Mezzanine floor areas with permanent access;
- Plant rooms, fuel & tank rooms, which are housed in a covered structure or a permanent nature, whether or not above the main roof level;
- Service accommodation such as toilets, bathrooms, changing rooms, cleaner’s rooms;
- Voids over stairwells and lifts;
- Areas with a headroom of less than 1.5m;
- Pavement vaults;
- Loading bays and garages;
- Structures, such as car ports with a solid roof even with one or more open sides;
- Porches even though the front or side(s) may be open;
- Conservatories;
- Basements, underground and covered car parking areas.
The following are excluded from CIL liable floorspace*:
- Perimeter wall thicknesses 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 (sheds), fuel stores and the like, in residential properties;
- A pergola with no roofing material;
- Free-standing solar panels.
*Note that each Council may differ in what is included and excluded in CIL liable floorspace and therefore it is advisable to check with them prior to planning any works. Alterntaively, seek professional assistance and make sure that your contract with your planning consultant includes completion of the right forms correctly at the right point in time. Please get in touch for more detail.