
Rear extension steels · Carrickfergus
Rear extension steels in Carrickfergus
Rear extension steels for homes in BT38, designed by a structural engineer.
- 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
What rear extension steels involve in Carrickfergus
Planning rear extension steels in Carrickfergus? Our team covers BT38 and the streets around them. Our coverage runs across Mid and East Antrim, so nearby villages are included too. You get one written quote for the calculations, approvals, propping, steel and making good.
We work alongside your builder or as the steel package within the wider build. We arrange the engineer's design, coordinate building control, prop and open the rear wall at the right stage of the programme, and fit and pack the steels so the extension can be finished around them.
Things to plan for
- Soil stacks, waste pipes, boiler flues and gas meters are often fixed to the back wall. These are moved before the wall opens, and any work on gas pipework must by law be carried out by a Gas Safe registered engineer.
- During the opening, props stand both inside the house and within the extension footprint. Where props bear on a newly laid slab, the propping plan checks that the slab can take those point loads, using spreaders where needed.
- A single beam works where solid masonry is left at both ends of the opening. Where the opening runs nearly the full width or the corners are weak, the engineer may use columns or a goalpost frame, which is two posts and a beam bolted together.
- The building control completion certificate for the extension covers the steelwork to the old rear wall. Keep it with the engineer's calculations and drawings, as a buyer's solicitor will expect to see the structural paperwork for the extension.
- In older houses the rear wall may be solid brick in lime mortar, with timber lintels and shallow footings beneath. The engineer may ask for trial holes to see what the wall stands on before deciding where the steel will bear.
From survey to sign-off in Carrickfergus
Survey in Carrickfergus
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
A full plans application or building notice goes to Mid and East Antrim Borough Council under the Building Regulations (Northern Ireland) 2012 before work begins.
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.
Guide prices for rear extension steels in Carrickfergus
As a guide, budget £2,150–£6,000 including VAT for opening into a rear extension in Carrickfergus, based on published UK cost guides adjusted for prices in Northern Ireland (-14%).
| Job | Typical guide range | What it usually covers |
|---|---|---|
| Opening into a rear extension | £2,150–£6,000 | Original rear wall removed with a beam or goalpost, approvals and propping, coordinated with the extension build |
| Structural calculations for a beam | £220–£640 | Site measure or photos, beam and padstone design and calculations for building control |
| Side return extension steelwork | £3,000–£7,300 | Beams and posts along the old side wall line, propping and approvals (extension build extra) |
| Rear wall opening for bi-fold or sliding doors | £2,150–£6,000 | External wall opened up to about 5 m with steel, propping, cavity tray and making good (doors supplied separately) |
Figures include our approximate regional adjustment for prices in Northern Ireland (-14%) and are rounded. How these figures are worked out.
Building rules for Carrickfergus
Building control in Carrickfergus is run by Mid and East Antrim Borough Council. Beams and new openings are controlled work under the Northern Ireland regulations, so we apply before anything is removed and the steel is inspected before it is covered.
The Party Wall etc. Act does not extend to Northern Ireland. Shared walls are dealt with under your title and the general law, so we recommend agreeing access and the work with your neighbour before it starts.
Rear extension steels near Carrickfergus
- Newtownabbey 5.6 mi
- Larne 9.3 mi
- Castlereagh 10.3 mi
- Lisburn 16.2 mi
- Antrim 16.2 mi
- Ballymena 21.3 mi
Rear extension steels in Carrickfergus: your questions
What happens at the survey visit in Carrickfergus?
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 soon can rear extension steels start in Carrickfergus?
Start dates depend on the engineer's calculations, the building control approval and any agreement needed with neighbours. We give you a realistic timetable after the survey and keep you updated as each approval comes through.
What is a goalpost frame in an extension?
A goalpost frame is two steel columns with a beam across the top, bolted together and standing on their own foundations. It is used where the opening is so wide that little masonry is left to bear on, or where the existing corners cannot take the load. The engineer decides whether one is needed.
Do I need a steel beam for my rear extension?
If the original back wall is being opened up into the extension, almost certainly yes. That wall normally carries the first floor and the wall above, so a beam, columns or a goalpost frame takes over the job. A structural engineer confirms exactly what is needed once the opening width and loads are known.
Who designs the steels for a rear extension?
A structural engineer. Your architect's drawings show the layout, but the engineer calculates the beams, columns, connections and foundations. We arrange those calculations, or work from an engineer's design you already have, and make sure the details suit the builder's programme.
Do you also work near Carrickfergus?
Yes. We also cover nearby towns including Newtownabbey, Larne, Castlereagh and Lisburn.