Class CB – temporary school buildings for RAAC affected schools
If a school is affected RAAC (Reinforced Autoclaved Aerated Concrete), Class CB allows for a temporary buildings to be erected until 24th October 2026. The building must not be within 5 metres of a residential C3 garden, nor be more than two storeys and not higher than 9 metres.
The maximum floor space is limited to 125% of the combined floor space of any RAAC buildings that have been vacated. The building(s) must be removed once the RAAC affected buildings are back in use.
If a school wishes to use Class CB to replace RAAC affected buildings they must notify the local authority with various required items (detailed in the legislation below) and also the local fire and rescue authority.
Where development begins after 25 October 2023, the school must notify the local authority either before or as soon as reasonably practicable after development has begun. Where development begins on or before 25 October 2023, the school must notify the local planning authority as soon as reasonably practicable after that date.
In notifying the local planning authority and fire and rescue authority, the school must provide a written description of the development, a plan showing the development and any buildings on the school’s school land, the start date or expected date for development, the address of the school and the school’s contact address. The school must also provide confirmation that there is a RAAC-affected building on the school’s school land and confirm the total floor space (in square metres) of school buildings that has been vacated due to RAAC and the total floor space (in square metres) of the temporary buildings being provided.
Planning Geek is able to assist with this procedure of required. Please make contact via the contact us form.
Should this be of interest to you then the full legislation for Class CB can be found below. This is a new permitted development right introduced on 25th October 2023 and is the twenty-seventh update to the GPDO which was last consolidated in 2015.
The full statutory instrument can be viewed here if interested.
What is RAAC?
Reinforced Autoclaved Aerated Concrete is a form of lightweight concrete used in construction in many buildings, both public and private sector, between the 1950s and 1990s. But it is thought to be more common is schools, hospitals and public buildings.
RAAC is highly aerated with different material properties to conventional concrete. It is mainly found in roofs, occasionally in floors and walls. Visually, RAAC planks may look the same as pre-cast concrete, and may be hidden above false ceilings. Read a more detailed explanation from The Institution of Structural Engineers.
It has been discovered in courts, theatres, sports halls, public toilets and a range of non-domestic buildings.
Class CB – temporary provision of buildings for a school with a RAAC-affected building
CB. The temporary provision of buildings on school land where the school has a RAACaffected building.
Development not permitted
CB.1. Development is not permitted by Class CB—
(a) if the school land covered by the building provided is, or forms part of—
(i) a site of special scientific interest,
(ii) a safety hazard area,
(iii) a military explosives storage area, or
(iv) a scheduled monument or land within its curtilage;
(b) if any part of any building provided would be within 5 metres of the boundary of the curtilage of land adjacent to the school land, where that adjacent land is used for a purpose within Part C (residential purposes) of Schedule 1 to the Use Classes Order(a);
(c) if any building provided would have more than two storeys;
(d) if the height of any building provided would exceed 9 metres;
(e) after the end of the period of three years beginning on 25th October 2023 and ending at 11.59 p.m. on 24th October 2026.
CB.2. Development is permitted by Class CB subject to the following conditions—
(a) the combined floor space of any buildings provided under Class CB is not more than 125% of the combined floor space of the parts of the RAAC-affected buildings which have been vacated due to the presence of RAAC;
(b) at the relevant time, the school must provide a written notification to the local planning authority which includes all of the following—
(i) the date or expected date of the beginning of development;
(ii) the address of the school;
(iii) the contact address for the school;
(iv) the size of the area, in square metres, of the combined floor space of the parts of the RAAC-affected buildings which have been vacated due to the presence of RAAC;
(v) the size of the area, in square metres, of the combined floor space of any buildings which form part of this development and any buildings provided under previous developments under Class CB (excluding buildings which are no longer provided);
(vi) a written description of the development;
(vii) a plan indicating the school’s school land, and any buildings on that land, and showing the development; (viii) confirmation that there is a RAAC-affected building on the school’s school land;
(c) at the relevant time, the school must also provide to the relevant fire and rescue authority a copy of the notification described in sub-paragraph (b);
(d) the development does not result in an increase to the school’s published admission number;
(e) buildings are placed so as to minimise, so far as practicable, any reduction in the amount of the school land—
(i) used as playing fields;
(ii) used as space available for the parking or turning of vehicles;
(f) any building provided under Class CB is removed from the school’s school land—
(i) as soon as reasonably practicable after such time as each RAAC-affected building on the school’s school land has been remediated or replaced; or
(ii) before the period in CB.1(e) has elapsed,
whichever is the sooner;
(g) following the removal of any building provided under Class CB, as soon as reasonably practicable the school land used in connection with the provision of that building is restored to the condition it was in before the development took place.
Interpretation of Class CB
CB.3. For the purposes of Class CB—
“published admission number” has the meaning given in paragraph M.3 of Part 7 of this Schedule;
“RAAC” means reinforced autoclaved aerated concrete;
“RAAC-affected building” means a building on school land which has been vacated, in whole or in part, pursuant to a decision by the school, in discharge of its health and safety obligations, that the building should be vacated due to the presence of RAAC;
“relevant time” means—
(a) where development begins after 25th October 2023, before development begins or as soon as reasonably practicable after it has begun;
(b) where development begins on or before 25th October 2023, as soon as reasonably practicable after that date;
“school” does not include buildings or land provided at any time under Class C or CA;
“school land” means land available for use by a school for a purpose falling within Class F.1(a) (provision of education) of Schedule 2 to the Use Classes Order.”.
Page Updated: 25th October 2023