Steel BeamInstallers
Ground-floor chimney breast removed with a short steel beam carrying the breast above

Chimney breast removal · Gwynedd

Chimney breast removal in Gwynedd

Calculations, approvals, propping, steel and making good for chimney breast removal across Gwynedd.

  • Free survey visit in Gwynedd
  • Engineer's calculations arranged
  • Building control handled for you

Free survey in Gwynedd

Tell us about your chimney breast removal project in Gwynedd.

Please enter your name.
Please enter a UK phone number.
Please enter a valid email.
Please enter a UK postcode.
Please tell us a little about the job.
  • Free survey visit
  • Engineer's calculations arranged
  • Building control handled
  • Fixed written price once scope is agreed
  • England, Wales, mainland Scotland & NI

About our chimney breast removal service in Gwynedd

Chimney breast removal is taking out the projecting brickwork that houses the flues from fireplaces, usually to gain floor space or straighten a wall. If any of the breast or stack above stays in place, it must be carried on steel or another support the engineer designs and building control accepts, so it is never left unsupported.

Chimney breast removal is one of the most common structural jobs in homes across Gwynedd. Coverage takes in Caernarfon, Porthmadog and Pwllheli and everywhere in between. Every job starts with a survey visit, then calculations from a structural engineer, so the steel suits the house in front of us rather than a rule of thumb.

Worth knowing before you start

  • Some owners remove breasts in the loft to make space for a conversion while keeping the stack on the roof. That leaves the stack carried at loft level on steel or another support, which the engineer must design and building control must approve before work starts.
  • A chimney breast removed without proper support or approval is a frequent issue raised in surveys when a house is sold. Keeping the calculations, completion certificate and any party wall documents shows a buyer that what remains was properly supported.
  • A chimney closed off at both ends can trap moisture and cause damp patches on the walls. Where part of a flue remains, a vent at room level and a ventilated cap on the pot keep air moving through it.
  • Once the breast is gone, the wall behind it is often rough, sooty or uneven. It is cleaned back, dubbed out where needed and plastered flat, and the floor where the hearth sat is filled level to meet the surrounding boards or screed.
  • The price depends on how many floors the breast spans, whether the stack is kept or removed, the support method the engineer specifies, roof and scaffold work, and how much rubble needs taking away. Each is listed separately in the quote.

How the job runs in Gwynedd

  1. Free visit

    A short visit to Gwynedd to see the job, agree what you want and check the bearings, floors and services that affect the design.

  2. Calculations

    The engineer's calculations and a simple drawing are prepared for your opening and shared with you before anything is ordered.

  3. Building control

    We submit the application or notice to Cyngor Gwynedd under the Building Regulations as they apply in Wales, before work starts.

  4. Steel in, made good

    On site we prop, open up, fit and pack the steel, then fire protect, box in and plaster once the inspection is done.

How much should I budget in Gwynedd?

As a guide, budget £1,350–£2,750 including VAT for chimney breast removal (ground floor) in Gwynedd, based on published UK cost guides adjusted for prices in Wales (-9%).

JobTypical guide rangeWhat it usually covers
Chimney breast removal (ground floor)£1,350–£2,750Ground-floor breast removed, steel to support the breast above, building control and making good
Party wall surveyor (agreed surveyor, per neighbour)£820–£1,820 per neighbourSchedule of condition and award where a neighbour dissents; serving notice alone, where the neighbour consents, costs far less (England and Wales only)
Loft conversion steels£2,300–£5,450Supply and fit of floor and ridge steels on padstones, including lifting into the roof space
Load-bearing wall removal with steel beam£1,800–£4,550Typical internal wall up to about 4 m: calculations, building control, propping, steel, padstones, fitting, fire protection and making good

Figures include our approximate regional adjustment for prices in Wales (-9%) and are rounded. How these figures are worked out.

Building rules for Gwynedd

Welsh building regulations treat beams and new openings as controlled building work. We apply to Cyngor Gwynedd on your behalf before anything is removed, give the commencement notice the 2026 Welsh rules require, and the steel is checked before it is boxed in.

The Party Wall etc. Act 1996 applies in Wales as well as England, so a beam bearing into a shared wall needs a party structure notice at least two months before work starts. We arrange notices through a party wall surveyor.

Building rules in Wales

Chimney breast removal by town

Local questions answered

Who approves chimney breast removal in Gwynedd?

Structural work in Gwynedd needs a building control application to Cyngor Gwynedd under the Welsh regulations, with a commencement notice before work starts. We prepare and submit it with the structural engineer's calculations and arrange the inspections, so the completion paperwork follows the job.

Can you work on older or listed homes in Gwynedd?

Yes. Older homes often have lime mortar, timber lintels or shallow footings, which the engineer allows for. Listed buildings need listed building consent for internal structural changes as well as building regulations approval, and that must be in place first.

How long does chimney breast removal take?

A ground-floor breast with a steel beam supporting the masonry above usually takes two to four working days, including propping, fitting the steel, removing the brickwork and basic making good. Full removal from ground floor to roof takes longer because of scaffolding, roofing work and weather, and plaster needs time to dry afterwards.

Can I remove a chimney breast on the ground floor only?

Yes, but whatever stays above must be properly supported. The structural engineer designs that support, usually a steel beam bearing onto walls that can take the load, and building control must approve it before work starts. Leaving an upper breast or stack without adequate support is dangerous and is a problem surveyors look for.

Can I remove a chimney breast downstairs and keep the fireplace upstairs?

Usually, as long as the upstairs breast and its flue stay intact and are carried on a support the engineer designs for that load. Building control must approve the arrangement. If the upstairs fireplace has a gas fire, any work on it or its supply must be carried out by a Gas Safe registered engineer.

What is included in a chimney breast removal quote?

The itemised written quote covers the survey, engineer's calculations, building control, any party wall notices, temporary support, the steel or other support specified, removal and waste, venting or capping, and plastering and floor making good. Scaffolding and roof work appear as separate lines where the stack is involved, and the price is fixed in writing once the scope is agreed.

Planning to take a wall out?

Book a free survey visit. You get an itemised written quote covering calculations, building control, steel and making good.