Ventilation for new builds, extensions and lofts in Hampshire

New homes, extensions and loft conversions need ventilation that meets the building regulations and is tested before sign-off. We design the system, install it at the right stage of the build, measure the airflows and provide the commissioning information building control asks for.

We carry out ventilation for new builds, extensions and lofts across Hampshire, including Southampton, Portsmouth, Basingstoke, Gosport and Waterlooville. Prices use South East rates. We survey first, free of charge for new installations on the mainland, then send a fixed written quote.

New builds & extensions in Hampshire at a glance

Area: Hampshire
Towns listed: 34, largest Southampton
Postcode districts: PO2, PO3, SO18, SO30, SO14 and SO15
Price region: South East
Survey: Free survey (UK mainland)

How we do it

For new dwellings in England, Approved Document F sets whole-home ventilation rates and requires mechanical systems to be commissioned and the results given to building control. Extensions and loft conversions have their own triggers: a new wet room needs extract, a new habitable room needs background ventilation or a connection to the ducted system, and energy-efficiency work can mean the existing home needs more ventilation too. We work for self-builders, small developers, builders and architects.

Commissioning only

Testing and paperwork for systems installed by others.

MVHR for new builds

Design, first fix, second fix and commissioning for whole-home heat recovery.

MEV or dMEV

Continuous extract systems where MVHR is not specified.

Guide prices in Hampshire

Ventilation for new builds, extensions and lofts guide prices in Hampshire
Work	Guide price
MVHR in a new build or full renovation (fitted at first fix), 3 to 4 bedrooms (per home)	£5,450–£8,750 inc VAT
Continuous-running extract fan (dMEV) with humidity boost, flow tested (per fan)	£380–£650 inc VAT
Airflow testing and commissioning sheet for extract fans (up to 6 fans) (per home)	£160–£325 inc VAT
MVHR or MEV commissioning test, every terminal measured and recorded (per system)	£270–£435 inc VAT

South East rates shown. Prices include VAT at 20%. The fixed price is confirmed in writing after we have seen the job.

When to get it looked at

Building control has asked for a ventilation strategy or commissioning sheet
Your SAP assessor has assumed a particular ventilation system
You are adding a bathroom or kitchen in an extension or loft

Rules in England

In England, ventilation is covered by Part F of the Building Regulations and its guidance, Approved Document F (2021 edition). 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

Drawings
Design
First fix
Second fix
Commission

Towns we cover in Hampshire

Questions about ventilation for new builds, extensions and lofts in Hampshire

Which towns in Hampshire do you cover?

All of Hampshire, including Southampton, Portsmouth, Basingstoke, Gosport and Waterlooville. If your town is not listed, send the postcode and we will confirm.

Who signs off the ventilation commissioning?

The installer measures the airflows and completes a commissioning sheet, which goes to building control; for new dwellings in England that is expected within five days of completion of the commissioning.

How much does MVHR cost in a new build?

For a 3 to 4 bedroom new build, MVHR fitted at first fix usually costs £4,950 to £7,950 including VAT. VAT on new-build work can differ, so we confirm the treatment on your quote.

Are prices different in Hampshire?

Our guide prices are adjusted by region. In Hampshire we use South East rates, so MVHR in a new build or full renovation (fitted at first fix), 3 to 4 bedrooms is typically £5,450 to £8,750 inc VAT per home.

Is the survey free in Hampshire?

For new installations on the UK mainland, yes. The survey is free and the quote that follows is fixed and in writing. Servicing, testing and repair visits are charged, and we confirm the cost before booking.