Ventilation for new builds, extensions and lofts in Somerset

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.

If you are anywhere in Somerset, send the postcode and a few photos and we will tell you what we would recommend. Towns we cover include Yeovil, Bridgwater, Portishead, Frome and Burnham-on-Sea.

New builds & extensions in Somerset at a glance

Area: Somerset
Towns listed: 19, largest Bath
Postcode districts: TA24, BS3, BS13, BA4, BA5 and BA4
Price region: South West
Survey: Free survey (UK mainland)

What ventilation for new builds, extensions and lofts involves

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. Fitting ducts at first fix is far cheaper than retrofitting, so it pays to involve us before the ceilings go up.

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 Somerset

Ventilation for new builds, extensions and lofts guide prices in Somerset
Work	Guide price
MVHR in a new build or full renovation (fitted at first fix), 3 to 4 bedrooms (per home)	£5,150–£8,250 inc VAT
Continuous-running extract fan (dMEV) with humidity boost, flow tested (per fan)	£360–£625 inc VAT
Airflow testing and commissioning sheet for extract fans (up to 6 fans) (per home)	£150–£305 inc VAT
MVHR or MEV commissioning test, every terminal measured and recorded (per system)	£255–£410 inc VAT

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

Signs it is time to call us

You are adding a bathroom or kitchen in an extension or loft
You are insulating and re-windowing an existing home
A self-build with an airtightness target

Rules in England

English building work follows Approved Document F (2021 edition) for ventilation rates, installation and commissioning. It sets extract rates for kitchens, bathrooms and utilities and asks for mechanical ventilation to be commissioned and recorded.

How the job runs

Drawings
Design
First fix
Second fix
Commission

Towns we cover in Somerset

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

Is the survey free in Somerset?

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.

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.

Can you just test a system someone else installed?

Yes. We can commission and test systems installed by others, and report any issues we find.

Which rules apply to ventilation in Somerset?

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.

Which towns in Somerset do you cover?

All of Somerset, including Yeovil, Bridgwater, Portishead, Frome and Burnham-on-Sea. If your town is not listed, send the postcode and we will confirm.