Structural engineering for two-storey extensions in County Armagh

County Armagh at a glance

Nation: Northern Ireland
Price region: Northern Ireland
Postcode areas: BT
Towns covered: 8 listed below, plus surrounding villages
Site visits: Free, no obligation

What a structural design involves

This service suits every two-storey extension, because each one needs foundations sized for two storeys and usually steel beams where walls are removed. You get a structural engineer's calculations and drawings for beams, padstones, lintels, foundations and connections, coordinated with the architectural drawings, submitted for building control and followed through on site by our build teams.

County Armagh towns we list: Craigavon (BT64), Portadown (BT62), Armagh (BT61), Moira (BT67), Keady (BT60) and Tandragee (BT63). Every other address in County Armagh is covered as well.

Fees

A structural engineer (calculations and beam design) is a guide of £750–£2,200, priced in writing once the design is known.

Rules in Northern Ireland

In Northern Ireland, structural design is checked by the council's building control service under the Building Regulations (Northern Ireland) and the relevant Technical Booklet. The engineer's calculations are submitted with the full plans, and building control inspects foundations, steelwork and other key stages during the build.

Approval in Northern Ireland: Planning application for works to a house: £347. Councils aim to decide local applications within an average of 15 weeks; many take longer.

Building control: Building control approval from the local council under the Building Regulations (Northern Ireland), using the Technical Booklets.

There is no Party Wall Act in Northern Ireland. Shared walls and boundaries are a matter of title and common law, so we agree access and record conditions with neighbours before work starts.

Getting the design right

Beams and padstones

Steel beams carry the first floor and roof over openings, and they sit on padstones that spread the load into the walls. The engineer sizes each beam and checks the walls can take the point loads, which affects ceiling heights and where posts can go.

Building on existing structure

When building over a garage or a single-storey extension, the engineer checks the existing footings, walls and lintels. Many were sized for one storey only and need underpinning, strengthening or replacement to carry the new floor.

How we work in County Armagh

Visit and first ideas
One of our team visits your house in County Armagh, checks the walls, roof and drains, and sketches out options with you.
Plans, then approval
Measured survey, design, then the right approval route for your house. We explain each step before we take it.
Structure and building control
A structural engineer sizes the foundations and steels, and we get building regulations approval before work starts.
Build
Foundations, walls, floor, roof, windows, then first and second fix. We break through into the house as late as we can.

Towns we cover in County Armagh

Structural engineering for two-storey extensions in County Armagh: questions

What are trial holes and why do I need them?

Trial holes are small excavations dug next to the house or garage to see the depth and condition of the existing foundations and the soil. They tell the engineer whether existing footings can be reused and how deep the new ones need to go, which avoids surprises during the build.

How deep do foundations need to be for a two-storey extension?

There is no single depth. It depends on the soil, nearby trees, drains and the loads. On firm ground foundations may be around a metre deep, while clay near trees can need much deeper trench fill or piles. Trial holes and the engineer's design set the depth, and building control inspects the trenches.

Can a steel beam be hidden in the ceiling?

Often, yes. A beam can sit within the floor depth so the ceiling is flat, but that may mean a deeper steel section or a different floor structure. Otherwise it shows as a downstand below the ceiling. We discuss the options with you and the engineer before the design is fixed.

Neighbouring areas

All extension services in County Armagh · About structural engineering for two-storey extensions