Airflow testing and commissioning in Hertfordshire

Airflow testing measures how much air each fan or valve actually moves, using a calibrated flow hood, and records it against the required rates. It is how you prove a ventilation system works, and for new homes it is part of the building regulations.

We carry out airflow testing and commissioning across Hertfordshire, including Hemel Hempstead, Stevenage, St Albans, Welwyn Garden City and Cheshunt. Prices use East of England rates. Servicing, testing and repair visits are charged, and we tell you the cost before booking.

Airflow testing in Hertfordshire at a glance

Area: Hertfordshire
Towns listed: 32, largest Watford
Postcode districts: WD2, WD24, AL3, AL4, WD1 and WD19
Price region: East of England
Survey: Charged visit, price agreed first

What airflow testing and commissioning involves

Approved Document F expects mechanical ventilation in new dwellings to be tested with a flow device that has been calibrated within the last 12 months, and the results recorded on a commissioning sheet. The person commissioning should be registered with a competent person scheme for ventilation or show evidence of competence; we tell you who will sign your sheet when we quote. Testing is also useful outside new builds: it shows landlords and homeowners whether existing fans meet the rates, and it is the first step in rebalancing an MVHR system that no longer feels right.

Extract fan tests

Each fan measured and compared with the Part F rate for the room.

MEV and dMEV commissioning

Trickle and boost rates measured and set.

MVHR commissioning

Supply and extract at every valve measured and balanced.

Guide prices in Hertfordshire

Airflow testing and commissioning guide prices in Hertfordshire
Work	Guide price
Airflow testing and commissioning sheet for extract fans (up to 6 fans) (per home)	£150–£310 inc VAT
MVHR or MEV commissioning test, every terminal measured and recorded (per system)	£255–£415 inc VAT
Rebalance and recommission an existing MVHR system (per system)	£255–£465 inc VAT

Guide prices using East of England rates. Prices include VAT at 20%. A guide price is not a quote: we confirm a fixed price in writing first.

Common reasons people call

You are selling a new build and the paperwork is missing
Fans seem weak and you want evidence
After MVHR or MEV installation by another company

Rules in England

English building work follows Approved Document F (2021 edition) for ventilation rates, installation and commissioning. For homes, it sets minimum extract rates such as 15 litres a second for a bathroom and 30 or 60 for a kitchen, and expects mechanical systems to be airflow-tested.

How the job runs

Book
Measure
Adjust
Record
Advise

Towns we cover in Hertfordshire

Questions about airflow testing and commissioning in Hertfordshire

Are prices different in Hertfordshire?

Our guide prices are adjusted by region. In Hertfordshire we use East of England rates, so airflow testing and commissioning sheet for extract fans (up to 6 fans) is typically £150 to £310 inc VAT per home.

What happens if a fan fails the test?

We explain the likely cause, such as an undersized fan or a crushed duct, and quote to fix it. Many failures are cheap to put right.

Is testing a legal requirement?

For new dwellings in England, mechanical ventilation must be commissioned and the results given to building control. For existing homes it is good practice and useful evidence.

Is the survey free in Hertfordshire?

This is a charged visit because it is servicing, testing or repair work. We tell you the cost before booking. Surveys for new installations on the UK mainland are free.

Which rules apply to ventilation in Hertfordshire?

In England, ventilation in new and altered homes is covered by Approved Document F of the Building Regulations. Landlords also have duties under the Housing Health and Safety Rating System, and workplaces must be ventilated under the Workplace (Health, Safety and Welfare) Regulations 1992.