For landlords, developers and anyone managing a building project, Part F of the Building Regulations sets the ventilation standards a property has to meet – and misunderstanding what it covers or when testing is required is one of the more common ways compliance gets missed until it’s too late to fix easily.
In this blog, you’ll learn:
- What the Part F Building Regulations actually cover
- Whether your project needs Part F ventilation testing
- Why Part F exists and what it’s protecting against
What Are the Part F Building Regulations?
Part F of the Building Regulations 2010 governs ventilation, air quality and condensation prevention in new-build properties. Ventilation, in this context, means replacing indoor air with fresh outside air – on purpose, rather than relying on incidental air leakage to do it.
Part F is actually split into two separate Approved Documents, each covering a different type of building:
- Approved Document F, Volume 1: Dwellings – covers domestic properties. Ventilation must circulate throughout the entire building; extract ventilation is required in humid or polluted areas (over an oven, for example) and purge ventilation allows intermittent rapid ventilation in habitable rooms, typically through windows or external doors.
- Approved Document F, Volume 2: Buildings other than dwellings – covers non-domestic properties. The priority here is continuous circulation of clean air, generally achieved through accessible, maintainable air conditioning systems that minimise the risk of airborne illness spreading.
Which volume applies depends entirely on the building type, not the project size or complexity – a small residential extension still falls under Volume 1, while a small commercial unit falls under Volume 2.
Do I Need Part F Ventilation Testing?
Fixed mechanical ventilation systems must be commissioned and tested to demonstrate compliance. This requirement doesn’t apply to buildings or spaces people don’t normally enter, spaces used solely for storage, or garages attached to a single dwelling – these don’t need ventilation testing.
Case Study: A Design-Stage Approach to Part L, F & O Compliance
On a nine-home development for Woodstock Homes, testing and commissioning ventilation systems alongside air tightness testing across all nine plots achieved full compliance with Parts L, F and O – with zero retests required.
Why Does Part F Matter?
Ventilation supplies the fresh air occupants need to breathe, dilutes pollutants and odours, and controls excess humidity. Without a system in place to remove excess water vapour, a building can develop condensation, dampness and the black mould that follows – which is exactly the outcome Part F exists to prevent.
Related Reading
- Ventilation Building Regulations: A Guide to Part F Compliance for New Builds – for how Part F applies in practice on a new build, including when mechanical ventilation is needed
- Ventilation for Airtight Homes: Why Sealing Up Isn’t Enough – for how Part F ventilation requirements interact with Part L air tightness
- Part F Ventilation Testing: How to Pass First Time – for what the test itself involves and how to avoid failing it
What’s next?
Understanding what Part F requires is the first step. Whether you’re planning a new development or need to confirm testing requirements for an existing project, getting advice early avoids compliance issues surfacing at the worst possible stage.
Every new build with a fixed mechanical ventilation system needs Part F testing to demonstrate compliance – get in touch to confirm what that means for your project or to get testing scheduled.
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