Floor area
According to the International Property Measurement Standards (IPMS): Residential Buildings, published by the International Property Measurement Standards Coalition (IPMSC) in September 2016, the floor area of a building is: 'The area of a normally horizontal, permanent, load-bearing structure for each level of a building.'
The Building Regulations define floor area as: '...the aggregate area of every floor in a building or extension, calculated by reference to the finished internal faces of the walls enclosing the area, or if at any point there is no such wall, by reference to the outermost edge of the floor.'
The glossary of statistical terms, published by the Organisation for Economic Co-operation and Development (OECD), states: ‘The floor area of buildings is the sum of the area of each floor of the building measured to the outer surface of the outer walls including the area of lobbies, cellars, elevator shafts and in multi-dwelling buildings all the common spaces. Areas of balconies are excluded.’
Resource Efficiency and Climate Change, Material Efficiency Strategies for a Low-Carbon Future, published by the UN Environment Programme in 2020, defines per capita floor area (m2/cap) as: ‘The average residential floor area available per person.’
See also:
- Total useful floor area.
- Gross floor area.
- Net internal area.
- Gross internal area.
- Treated floor area.
- Floor area ratio.
- Effective Floor Area.
- Floor area of the room.
[edit] Related articles on Designing Buildings
Featured articles and news
A case study and a warning to would-be developers
Creating four dwellings... after half a century of doing this job, why, oh why, is it so difficult?
Reform of the fire engineering profession
Fire Engineers Advisory Panel: Authoritative Statement, reactions and next steps.
Restoration and renewal of the Palace of Westminster
A complex project of cultural significance from full decant to EMI, opportunities and a potential a way forward.
Apprenticeships and the responsibility we share
Perspectives from the CIOB President as National Apprentice Week comes to a close.
The first line of defence against rain, wind and snow.
Building Safety recap January, 2026
What we missed at the end of last year, and at the start of this...
National Apprenticeship Week 2026, 9-15 Feb
Shining a light on the positive impacts for businesses, their apprentices and the wider economy alike.
Applications and benefits of acoustic flooring
From commercial to retail.
From solid to sprung and ribbed to raised.
Strengthening industry collaboration in Hong Kong
Hong Kong Institute of Construction and The Chartered Institute of Building sign Memorandum of Understanding.
A detailed description from the experts at Cornish Lime.
IHBC planning for growth with corporate plan development
Grow with the Institute by volunteering and CP25 consultation.
Connecting ambition and action for designers and specifiers.
Electrical skills gap deepens as apprenticeship starts fall despite surging demand says ECA.
Built environment bodies deepen joint action on EDI
B.E.Inclusive initiative agree next phase of joint equity, diversity and inclusion (EDI) action plan.
Recognising culture as key to sustainable economic growth
Creative UK Provocation paper: Culture as Growth Infrastructure.





















