Basement & cellar steels · Antrim and Newtownabbey
Basement & cellar steels in Antrim and Newtownabbey
Basement & cellar steels across Antrim and Newtownabbey, designed by a structural engineer and signed off by building control.
- Survey, design and installation in one
- Covering BT29, BT36, BT37, BT39
- Inspected before it is covered
- Free survey visit
- Engineer's calculations arranged
- Building control handled
- Fixed written price once scope is agreed
- England, Wales, mainland Scotland & NI
What basement & cellar steels involve in Antrim and Newtownabbey
Basement and cellar steels are the beams and columns that hold up the house above when walls are removed, openings are formed or new space is dug out below ground level. They carry the ground floor and walls down to new foundations, and are installed in a sequence set out by a structural engineer, alongside underpinning, excavation and waterproofing.
We carry out basement & cellar steels throughout Antrim and Newtownabbey, for homeowners, landlords and builders who need the structural part done properly. Towns we cover include Newtownabbey and Antrim, among other places in the area. You get an itemised written quote that shows the calculations, approvals, steel, labour and finishing as separate lines.
Worth knowing before you start
- Victorian and Edwardian cellars often have shallow brick walls, vaulted coal stores extending under the front garden or pavement, and little or no damp protection. The engineer checks whether vaults and walls can stay and what new support they need.
- Temporary works for basements are more involved than for a single opening. The design covers propping the house above, supporting the sides of the excavation, and keeping loads off freshly cast concrete until it has gained strength.
- Basements can stay damp even with waterproofing in place, so steel used below ground is protected against corrosion as the engineer specifies. That might mean an upgraded paint system or galvanising, particularly where steel sits close to external walls.
- Basement steel frames often rely on columns because there is nowhere else to land the load. Each column sits on its own foundation or a thickened part of the slab, and its position needs agreeing early so it does not end up in the middle of a room.
- Converting a cellar into a habitable room is building work needing building regulations approval, covering structure, fire escape, ventilation and damp protection. Digging out a new basement may also need planning permission, depending on the council and the scale of the work.
How the job runs in Antrim and Newtownabbey
Survey in Antrim and Newtownabbey
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 Antrim and Newtownabbey 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.
What do basement & cellar steels cost in Antrim and Newtownabbey?
As a guide, budget £2,150–£5,600 including VAT for basement or cellar steelwork in Antrim and Newtownabbey, based on published UK cost guides adjusted for prices in Northern Ireland (-14%).
| Job | Typical guide range | What it usually covers |
|---|---|---|
| Basement or cellar steelwork | £2,150–£5,600 | Beams and columns with pad foundations under the floor above (excavation and waterproofing extra) |
| Fire protection to a steel beam | £130–£520 per beam | Fire-rated board boxing or an intumescent coating system as specified |
| Steel column or post | £430–£1,290 per column | Column supplied and fitted with base and cap plates on a pad foundation |
| Structural calculations for a beam | £220–£640 | Site measure or photos, beam and padstone design and calculations for building control |
Figures include our approximate regional adjustment for prices in Northern Ireland (-14%) and are rounded. How these figures are worked out.
Approvals in Antrim and Newtownabbey
Building control in Antrim and Newtownabbey is run by Antrim and Newtownabbey 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.
Basement & cellar steels by town
Basement & cellar steels in Antrim and Newtownabbey: your questions
How soon can basement & cellar steels start in Antrim and Newtownabbey?
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.
How much do basement & cellar steels cost in Antrim and Newtownabbey?
As a guide, budget £2,150–£5,600 including VAT for basement or cellar steelwork in Antrim and Newtownabbey, based on published UK cost guides adjusted for prices in Northern Ireland (-14%). 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.
Will columns be needed in my basement?
Quite often. Below ground there may be no suitable wall to support the end of a beam, so a column carries the load down to a foundation. The position can usually be agreed with you at design stage so the column sits within a wall line, a kitchen island or a storage area.
How is steel protected from damp in a basement?
Steel below ground is protected against corrosion as the engineer specifies, which may mean a heavier-duty paint system or galvanising. It is also kept on the dry side of the waterproofing where possible, and fixings through the waterproofing are detailed so they do not let water in.
Can I stay at home while basement steels are installed?
Many people do, particularly for cellar conversions where the dig is limited. Expect noise, dust and deliveries during the heavier stages, and some rooms above may be out of use while props are in place. For large excavations, moving out for part of the programme can be more comfortable.
Do you do the underpinning for a basement?
Underpinning is specialist work, and we coordinate the steelwork with the underpinning contractor rather than carrying it out ourselves. The engineer designs the steel and the underpinning sequence together, so beams, columns and new foundations fit the order in which the walls are deepened.
Do I need a party wall agreement for basement & cellar steels in Antrim and Newtownabbey?
There is no Party Wall Act in Northern Ireland. Your title deeds and the general law apply instead, so agree the work with your neighbour in writing before it starts.