Installed capacity of a fixed building service per unit area
Installed capacity refers to the maximum output that a system, typically related to energy generation or consumption, can produce under optimal conditions. This is commonly used in reference to renewable energy installations (such as solar panels or heat pumps), combined heat and power (CHP) systems, or battery storage capacity within a building.
Approved document L, Conservation of Fuel and Power, Volume 2: Buildings other than dwellings, 2021 edition incorporating 2023 amendments, defines the installed capacity of a fixed building service per unit area as: ‘The design output of the distribution system output devices (the terminal units) serving the space in question, divided by the total useful floor area of that space.’
See also: Installed capacity.
[edit] Related articles on Designing Buildings
- Approved document L.
- Approved documents.
- Building regulations.
- Energy.
- Fuel.
- Heating.
- Hot water.
- Installed capacity.
- Power.
Featured articles
Check out some of the best features and news from Designing Buildings as well as key stories from around the web.
New measures to stop people being ripped off
Government to protect families from cowboy builders and aggressive bailiffs.
New Futurebuild showcase brings an innovation-first approach.
National Planning Policy Framework
Understanding the 2026 changes.
ECA's public affairs priorities
Member consultation opens to shape priorities for 2027 to 2030.
Dutyholder responsibilities from 1 July 2026.
Where performance meets practice
The Building Envelope Stage at UKCW Birmingham.
CIAT publishes briefing on planning reforms.
Leaders in Learning for Practice Network
Call for conservation leaders in learning to register interest in new network.
The importance of early engagement
Construction lessons from the Trillium HealthWorks Experience Centre.
Mayors are to be given planning call in powers
Mayors across England will be able to make the most important planning decisions.
The Master Builder: William Butterfield and his times. Book review.
Why construction can't afford to ignore the skills gap.