Why do you need vent testing?
Approved Document F requires extraction ventilation in houses and flats to demonstrate they are achieving the air flow rates required to maintain air quality. The requirements apply to kitchens, bathrooms, toilets and utility rooms in new dwellings and, as of June 2022, conversions and extensions as well.
What we offer
Air flow rate measurement of domestic extract ventilation i.e. intermittent (System 1) and Continuous (System 3) extractor fans and cooker hoods for Approved Document F compliance.
What is vent testing?
Air flow is typically measured using a vane anemometer connected to a hood that is fitted over the vent to channel the air flow. Results are available immediately. Where the air flow measured is a little under that required by Building Regulations some leeway is allowed in some circumstances to allow for the limitations of the test method, in these cases a define benchmark value is considered to be acceptable.
The requirements for different vents varies depending upon their location and type:
Intermittent Extraction (i.e. vents that are only switched on when required):
| Room Type | Air flow rate (l/s) |
|---|---|
| Kitchen | 30 |
| Utility room | 30 |
| Bathroom/En-suite | 15 |
| Toilet | 6 |
Continuous Extraction (i.e vents that run all the time at a low ‘trickle’ but can be ‘boosted’ when required)
| Room Type | Air flow rate (l/s) |
|---|---|
| Kitchen | 13 |
| Utility room | 8 |
| Bathroom/En-suite | 8 |
| Toilet | 6 |
Common problems include:
- Under specification of the fan – most often in utility rooms where bathroom vents are fitted
- Twists, kinks or tight turns in the flexible hosing
- Extended runs of flexible hosing
- Narrowing of the opening e.g. by the hosing being concertinaed
- Obstruction of the hosing or external grille
ACCREDITATIONS
