Fire protection for steel beams · Caerphilly
Fire protection for steel beams in Caerphilly
Fire protection for steel beams across Caerphilly, designed by a structural engineer and signed off by building control.
- Free survey visit in Caerphilly
- Engineer's calculations arranged
- Building control handled for you
- Free survey visit
- Engineer's calculations arranged
- Building control handled
- Fixed written price once scope is agreed
- England, Wales, mainland Scotland & NI
Fire protection for steel beams in Caerphilly: how it works
Fire protection for steel beams is the layer of fire-rated board or intumescent coating applied to structural steel so it keeps its strength long enough in a fire for people to get out. Steel softens as it heats, so building regulations set a period of fire resistance for beams and columns, and the protection is chosen and applied to meet that period.
Homes across Caerphilly range from Victorian terraces to post-war semis and newer estates, and fire protection for steel beams looks different in each. That includes Risca, Gelligaer and Blackwood, plus smaller towns and villages nearby. We plan the steel, the temporary support and the approvals around the building, then fix the price in writing once the scope is agreed.
Things to plan for
- Damaged boxing or chipped intumescent paint should be repaired properly, not patched with ordinary filler. Small chips in a coating can usually be touched up with the same system, while a dented or holed box may need that board section replaced.
- Boxing a single beam usually takes around a day, plus skimming and drying. Intumescent coatings need each coat to dry before the next goes on, so they can take several days depending on the thickness required and the room temperature.
- A common fault is applying intumescent paint over the wrong primer, or over one of unknown type. The products must be compatible, so where steel was primed long ago the primer is identified or the surface is cleaned back before coating.
- Building control treats fire protection as part of the structural approval, not an optional extra. If unprotected steel is found at inspection, the completion certificate is normally held back until the protection is in place and has been checked.
- Boxing is generally the lower-cost route for steel that will be hidden. Intumescent coatings cost more because of the product and the number of coats, and the price rises with the fire period and the size of the section.
How the job runs in Caerphilly
Free visit
A short visit to Caerphilly to see the job, agree what you want and check the bearings, floors and services that affect the design.
Calculations
The engineer's calculations and a simple drawing are prepared for your opening and shared with you before anything is ordered.
Building control
We submit the application or notice to Caerphilly County Borough Council under the Building Regulations as they apply in Wales, before work starts.
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 Caerphilly?
As a guide, budget £140–£550 per beam including VAT for fire protection to a steel beam in Caerphilly, based on published UK cost guides adjusted for prices in Wales (-9%).
| Job | Typical guide range | What it usually covers |
|---|---|---|
| Fire protection to a steel beam | £140–£550 per beam | Fire-rated board boxing or an intumescent coating system as specified |
| Steel column or post | £460–£1,360 per column | Column supplied and fitted with base and cap plates on a pad foundation |
| RSJ supply and fit (single beam) | £730–£2,280 per beam | Beam supplied, delivered, lifted and packed on padstones, with propping (calculations and approval priced separately) |
| Structural calculations for a beam | £230–£680 | Site measure or photos, beam and padstone design and calculations for building control |
Figures include our approximate regional adjustment for prices in Wales (-9%) and are rounded. How these figures are worked out.
Building rules for Caerphilly
Welsh building regulations treat beams and new openings as controlled building work. We apply to Caerphilly County Borough Council 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.
Questions about fire protection for steel beams in Caerphilly
What happens at the survey visit in Caerphilly?
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.
How much does fire protection for steel beams cost in Caerphilly?
As a guide, budget £140–£550 per beam including VAT for fire protection to a steel beam in Caerphilly, based on published UK cost guides adjusted for prices in Wales (-9%). The exact figure depends on the span, what the wall carries, access and the finish, and is fixed in writing once the scope is agreed.
Is boxing in a steel beam cheaper than intumescent paint?
Usually, yes. Boxing with fire-rated plasterboard tends to cost less for steel that will be hidden. Intumescent coatings generally cost more because of the product and the number of coats needed, but they let the beam stay visible. Where either method would work, both can be priced on the itemised quote so you can compare.
Can I box in a steel beam with normal plasterboard?
Not where fire protection is required. Standard plasterboard is not designed to protect steel for a set period in a fire. Fire-rated plasterboard is used instead, fixed in the number of layers and with the fixings the system specifies, so the boxing performs as intended and passes when building control checks it.
How thick does intumescent paint need to be on a steel beam?
There is no single figure. The thickness depends on the steel section, how many sides are exposed and the fire period required, and the coating manufacturer's data sets the dry film thickness for each case. The applied thickness is measured with a gauge once the coats have dried and recorded for building control.
How long does intumescent paint take to apply?
Several days in most cases. Each coat has to dry before the next is applied, and the number of coats depends on the thickness needed. Cold or damp rooms slow drying, so the space is kept warm and ventilated, and the top coat goes on once the full build has been measured.
Who approves fire protection for steel beams in Caerphilly?
Structural work in Caerphilly needs a building control application to Caerphilly County Borough Council 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.