Common developments and their CIL

As noted in the previous section, ultimate responsibility for determining exact CIL liability lies with Council (and can be complex for certain developments).

However, If you consider that your development is likely to be CIL liable, then you should submit CIL forms 1 and 2 along with your planning application.

Before you submit the form or make final decisions on your development you might like to know more about the CIL charge and whether you willlneed to pay anything. As such, we have put together a list of some common developments to help you get an idea of whether a particular development may be liable.

Generally speaking, a development is potentially liable for CIL if it meets the following: 

• it results in a net increase in GIA of 100m2 or more (any use)
• it results in the creation of a new residential unit with net additional floor space/GIA (however small)

Note: GIA stands for “Gross Internal Area”

Deduction for existing in use buildings

However, you will be able to deduct the demolished floor space will be deducted from the new floor space, providing it has been in lawful use for 6months in the previous 3years prior to the date of the planning permission. So, if you demolish an existing 2storey dwelling (GIA of 150m2) to construct a 3 storey building comprising 5 flats (GIA of 550m2), then the liable floorspace would be: 550m2 - 150m2 = 400m2

Domestic Extensions/Annexes

Generally, most extensions do not increase the GIA of a building by more than 100m2, and as such, are not liable for CIL. However, If an extension does exceed this threshold, then it is likely that this would qualify for a residential/extension CIL exemption.

Replacement dwellings

These developments are technically liable for CIL due to the fact that they create a new residential unit. However, if you are planning on living in the new dwelling as your new primary home, then you may qualify for a self build exemption.

Extensions and conversion of a dwellinghouse into flats.

As new residential units are being created, this is CIL liable. However, subject to the existing dwellinghouse having been “in use” (see above), only the additional floorspace (GIA) created by the extensions would be chargeable. So, if you have an existing occupied house with a GIA of 200m2, and you permission is for part single, part first floor extensions totalling 45m2 to facilitate the conversion of the property to 2 flats, then your liable floorspace would be 45m2.

S73 (Minor Material amendment) applications

If you have received planning permission for amendments to the scheme which change the permitted amount of GIA/floorspace, then the new application may become liable for CIL to a greater or lesser degree. Under a Section 73 application, any additional floor space created through the new permission will be liable for CIL (likewise, any floor space lost would no longer be liable). A new/additional Liability Notice for this revised amount will be issued in these circumstances.

CIL break down by site type

Current site: Cleared building site

• Proposed development: New residential dwelling with GIA of 150m2
• CIL liable? Yes
• Chargeable area: 150 square metres

Current site: Single dwelling in lawful use

• Proposed development: (Domestic) Single Storey extension (GIA = 30 square metres)
• CIL liable? No
• Chargeable area: None, the extension is less than 100 square metres and does not result in the formation of a new dwelling

Current site: Extended Retail with Residential on upper floors

• Proposed development: Extensions on ground and upper floors to provide 110m2 of additional retail floorspace and two additional residential units on the upper floors (95m2)
• CIL liable? Yes
• Chargeable area: 110m2 charged at the Retail rate and 95m2 charged at Residential CIL rate.

Current site: Cleared building site

• Proposed development: Residential block of flats (3,000 square metres) providing 33% per cent social housing (1000 square metres)
• CIL liable? Yes
• Chargeable area: 2000 square metres liable. 1000 square metres would qualify for social housing relief subject to successful application. You must apply for the affordable housing relief and get confirmation of the relief prior to commencement.

Current site: Single dwelling in lawful use being demolished

• Proposed development: 130 square metres new development, 80 square metres being demolished
• CIL liable? Yes
• Chargeable area: 50 square metres would be CIL liable. To qualify for this deduction the area to be demolished must still exist when the development is first permitted, and have been in lawful use for a continuous period of six months within the period of three years ending on the day planning permission first permits the chargeable development.

Current site: Single dwelling not in lawful use but being demolished

• Proposed development: 130 square metres new development, 80 square metres being demolished.
• CIL liable? Yes
• Chargeable area: 130 square metres would be CIL liable. If the area to be demolished has not been in lawful use for a continuous period of three years ending on the day planning permission first permits the chargeable development, then the area to be demolished cannot be deducted when calculating CIL.

Current site: Vacant (Long term) Retail unit.

• Proposed development: 98 square metres change of use to residential
• CIL liable? Very Likely
• Chargeable area: 98m2. If the retail unit has been vacant for a long time, ie it has not been in use for at least six continuous months in the previous three years prior to the date of the planning permission, then the existing floor space cannot be discounted, and as a new residential unit is being created, this is liable.

Current site: Occupied Retail unit

• Proposed development: 98 square metres change of use to residential
• CIL liable? No
• Chargeable area: 0m2. As the retail unit has been in continuous lawful use for at least six months in the last three years and the building will be retained when the development is completed, the

Current site: Cleared building site

• Proposed development: Varying application under Section 73 to enlarge GIA of existing new flatted development by 20 square metres
• CIL liable? Yes
• Chargeable area: 20 square metres additional CIL liability generated.

Current site: 4,000 square metres of office in lawful use

• Proposed development: 4,000 square metres change of use/conversion from office to residential
• CIL liable? No
• Chargeable area: Not liable as the development does not create new floor space and has been in lawful use for a continuous period of six months in the last three years ending on the day planning permission first permits the chargeable development.

Current site: 2,000 square metres of office space in lawful use

• Proposed development: Demolition of existing office building (GIA of 2000m2). Erection of replacement mixed used building providing 30 new residential units (GIA of 3000m2) and 1000m2 of retail space.
• CIL liable? Yes
• Chargeable area: Assuming that the existing office space is in lawful use and can be deducted from the development then the demolished floor space discount would be proportionately discounted across the development. In this example 75 per cent of the discount applies to the residential development and 25 per cent on the retail development. Therefore of the 2,000 square metres deduction, 1500 square metres is deducted from the new residential floor space and 500 square metres from the retail development. Any qualifying relief (eg for any affordable housing units) could also be applied for and further discounted from the total.