Plastering & making good · Gwynedd
Plastering & making good in Gwynedd
Plastering & making good across Gwynedd, designed by a structural engineer and signed off by building control.
- Price fixed in writing once scope is agreed
- Building control arranged
- Temporary works and making good included
- Free survey visit
- Engineer's calculations arranged
- Building control handled
- Fixed written price once scope is agreed
- England, Wales, mainland Scotland & NI
Plastering & making good in Gwynedd: how it works
Plastering and making good is the finishing work after a beam goes in or a wall comes out: boxing the steel, fixing corner beads, patching ceilings and wall ends, infilling the floor where the wall stood and skimming everything smooth. The aim is a room that looks as if the opening was always there, ready for paint.
Homes across Gwynedd range from Victorian terraces to post-war semis and newer estates, and plastering & making good looks different in each. We work in Pwllheli, Dolgellau and Porthmadog and the surrounding villages. We plan the steel, the temporary support and the approvals around the building, then fix the price in writing once the scope is agreed.
Key points for your project
- Fire-rated plasterboard is used for boxing steel that needs fire protection, while standard or moisture-resistant board suits ordinary ceiling and wall repairs. Using the right board in each place avoids rework when building control inspects.
- Making good is easy to underestimate when budgeting. Removing a wall disturbs the ceiling, both wall ends and the floor, and props and needles leave their own marks, so the finishing work usually covers far more than the opening itself.
- Plastering itself is wet rather than dusty, but cutting back old plaster and sanding filler is not. Work areas are sheeted off, floors protected and dust extraction used when cutting, so the mess stays in the room being worked on.
- New plaster is very absorbent, so the first coat of emulsion is normally thinned with water as a mist coat to seal it. Skipping this step is a frequent reason paint flakes off fresh plaster within weeks of decorating.
- Metal angle beads on every outside corner of the boxing give crisp, straight lines and protect the edges from knocks. They are set true to the ceiling and walls, so a slightly out-of-level beam does not show once skimmed.
From survey to sign-off in Gwynedd
Survey in Gwynedd
We visit, look at the wall and what sits above it, measure the opening and note services, access and how the steel can be brought in.
Engineer's design
A structural engineer sizes the beam, padstones and any posts, and sets out the temporary support needed while the wall is out.
Building control
We submit the application or notice to Cyngor Gwynedd under the Building Regulations as they apply in Wales, before work starts.
Install and sign-off
Props go in, the opening is formed, the steel is set and packed, building control inspects it, and we make good.
What does plastering & making good cost in Gwynedd?
As a guide, budget £270–£1,090 including VAT for plastering and making good in Gwynedd, based on published UK cost guides adjusted for prices in Wales (-9%).
| Job | Typical guide range | What it usually covers |
|---|---|---|
| Plastering and making good | £270–£1,090 | Boxing the beam, bead and skim, reveals, floor infill where the wall stood and tidy-up |
| Through-lounge knock-through | £2,300–£5,000 | Wall between front and back reception rooms, steel beam, approvals, plastering and floor infill |
| Chimney breast removal (ground floor) | £1,350–£2,750 | Ground-floor breast removed, steel to support the breast above, building control and making good |
| Fire protection to a steel beam | £140–£550 per beam | Fire-rated board boxing or an intumescent coating system as specified |
Figures include our approximate regional adjustment for prices in Wales (-9%) and are rounded. How these figures are worked out.
Building rules for Gwynedd
In Wales, structural alterations come under the Building Regulations 2010 as they apply in Wales. Cyngor Gwynedd handles building control for Gwynedd. For work started or approved from 1 July 2026, the Welsh system uses an application to building control, dutyholders appointed in writing, a commencement notice before work starts and a compliance statement at the end.
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.
Plastering & making good by town
Questions about plastering & making good in Gwynedd
What happens at the survey visit in Gwynedd?
We look at the wall, the floor and ceiling either side and what sits above, measure the opening you want, and note cables, pipes and access for the steel. It usually takes under an hour and there is no charge.
Can I stay at home while the work is done in Gwynedd?
Usually, yes. The work area is screened and floors are protected. The rooms either side of the opening are out of action for a few days, and there is some noise and dust while the masonry comes out.
Can you repair a lath and plaster ceiling?
Yes. Small areas can be patched with lath and lime-based plaster, or with board cut in and skimmed to match. Where large areas have sagged or pulled away from the laths, overboarding or replacing the ceiling is often the sounder repair. We assess the condition at the survey and price the right approach.
Do you decorate after making good?
Not usually. Making good leaves surfaces skimmed, dry and ready for paint, with trims refitted, and decoration is normally left to you or your decorator so you can choose colours and finishes yourself. Whoever paints should start with a thinned mist coat on the new plaster before the main coats.
Do you replace skirting boards and door frames after a knock-through?
Yes, where the work affects them. Skirting is extended or replaced so it runs through the new opening, and door linings and architraves are refitted or replaced where an opening has changed. Where period mouldings are involved, matching profiles can usually be sourced or made up to suit.
How do you hide a steel beam in the ceiling?
Most beams are boxed with fire-rated plasterboard fixed to a light frame, then finished with corner beads and a skim coat so they read as part of the ceiling. If you want no downstand at all, the beam has to be set into the floor void when it is installed, which is decided at the design stage.
Which towns in Gwynedd do you cover?
We cover towns including Bangor, Caernarfon, Pwllheli and Porthmadog, plus the villages and smaller towns around them.