Free area
Domestic Ventilation Compliance Guide, 2010 Edition (with 2011 amendments), published by the Department for Communities and Local Government in July 2011, suggests that the term ‘free area’ refers to: ‘…the geometric open area of a ventilator of terminal.’
Approved Document O: Overheating, published by HM Government in 2021, defines free area as: ‘The geometric open area of a ventilation opening. This area assumes a clear sharp-edged orifice that would have a coefficient of discharge (Cd) of 0.62.’
Approved document F: Volume 1: Dwellings, 2021 edition, defines free area as: ‘The geometric open area of a ventilator.’
see also Equivalent area and Discharge coefficients, free, effective and equivalent areas
[edit] Related articles on Designing Buildings
- Air change rates.
- Approved Document F.
- Background ventilator.
- Cross ventilation.
- Discharge coefficients, free, effective and equivalent areas.
- Displacement ventilation.
- Equivalent area.
- Heat recovery ventilation.
- Mechanical ventilation.
- Natural ventilation.
- Stack effect.
- Thermal comfort.
- Underfloor air distribution.
- Ventilation.
- Whole building ventilation.
Featured articles
Check out some of the best features and news from Designing Buildings as well as key stories from around the web.
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.
CIAT responds to Climate Change Committee report
An urgent wake-up call for both government and the built environment.
Construction Management, 24 June
FMB pilot aims to build pipeline of site-ready tradespeople.
A quick introduction.
CLC publishes Mental Health Joint Code of Practice.
A quick introduction to its uses and risks.
Construction Management, 17 June
Government rolls out digital planning tool to all local authorities.
Your views needed - a strategy for the professions, trades and occupations.