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.
Passive fire protection webinar
MEP services penetration seals.
Where its at podcast (and video) - The role of the Architectural Technologist as an Expert Witness.
More than 200 remarkable buildings added to SAVE’s Buildings at Risk register.
Government scraps pre-application consultation for Nationally Significant Infrastructure Projects.
Historic England and infrastructure
New projects offer opportunities for the historic environment and local communities.
Construction Management, 2 July
Construction deaths halve in two years.
Green Book changes to drive investment in all parts of UK.
Minimum energy efficiency standards (MEES)
CIAT briefing on response to consultations for privately rented non-domestic properties.
Connect, collaborate, shape the future
Registration now live for UK Construction Week Birmingham.
CIOB announces Saul Humphrey FCIOB as new President for 26/27 term.
A quick, simple, and zero-bills solution to prevent overheating.
The adaptive reuse of large industrial structures.
Promoting the circular economy by extending the life of buildings.

















