Thermal element
Thermal element is defined in regulation 2(3) and 2(4) of the Building Regulations as follows.
2(3) In these Regulations “thermal element” means a wall, floor or roof (but does not include windows, doors, roof windows or roof-lights) which separates a thermally conditioned part of the building (“the conditioned space”) from—
- a. the external environment (including the ground); or
- b. in the case of floors and walls, another part of the building which is— i. unconditioned; ii. an extension falling within class 7 of Schedule 2; or iii. where this paragraph applies, conditioned to a different temperature,
and includes all parts of the element between the surface bounding the conditioned space and the external environment or other part of the building as the case may be.
2(4) Paragraph 2(3)(b)(iii) only applies to a building which is not a dwelling, where the other part of the building is used for a purpose which is not similar or identical to the purpose for which the conditioned space is used.
NB Manual to the Building Regulations, A code of practice for use in England, published by the Ministry of Housing, Communities and Local Government (MHCLG) in July 2020, defines a thermal element as: ‘a material that contributes to the thermal performance of a building’s thermal envelope, such as any element of a wall, floor or roof but not a door or window. Thermal element is defined in Regulation 2(3) of the Building Regulations.’
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