New build house structural design
A new build house is designed from the ground up, so every load path is yours to set rather than inherit. We provide the foundation, frame and floor design that proves the house stands up and satisfies Building Control, for self-builders, architects and developers across the UK.
Do I need a structural engineer to build a new house?
Yes. A new build needs designed foundations, a designed superstructure and lateral stability, all of which Building Control assesses against Approved Document A. We prepare the full calculation and drawing package for the Building Regulations submission.
Designing the house from the ground up
Unlike an extension, a new build has no existing structure to work around, which means the whole load path is decided at design stage. Roof loads gather onto the wall plate, travel down through the external and internal loadbearing walls or a timber frame, pass through the ground floor structure and land on the foundations. We set out that path early so the walls that need to carry weight are in the right place and the openings you want do not leave a beam stranded with nowhere to bear.
We size every principal member: the ridge and hip arrangement, purlins where the roof spans call for them, floor joists or engineered I-joists at the correct centres, lintels and beams over large openings and bi-fold runs, and the steelwork picking up any upper storey that sits over open-plan space below. The output is a coordinated calculation package and drawings your builder can price and your Building Control body will accept without a run of queries.
Foundations for a virgin plot
On a new plot the foundation is set by the ground, not the floor plan, and it is usually the single biggest structural cost. We assess the soil type, water table, slope, any nearby trees and the results of a site investigation where one exists, then design a strip, trench-fill, raft or piled solution to suit. Shrinkable clay near mature trees can push a trench-fill foundation well beyond a metre deep, while soft or made ground may make a raft or short-bored piles the cheaper answer overall.
We also design the ground floor to match: a beam and block floor spanning onto the foundations, a suspended in-situ slab, or a ground-bearing slab where the fill and subgrade allow it. Getting the foundation and floor decision right at the start avoids the expensive redesign that happens when trial holes come back worse than hoped.
Coordinating with the architect and Building Control
We work from the architect's plans and elevations and coordinate the structure with the design intent before anything is set on site. Open-plan living, large glazed openings and slender feature staircases all have structural consequences, and it is far cheaper to resolve them on paper than to discover them once the walls are up. Where the architecture is ambitious we tell you what the structure needs and offer alternatives that keep the look.
The calculations are prepared to the Eurocodes, BS EN 1990 through 1999, the relevant UK National Annex and Approved Document A, so they demonstrate compliance for the full plans Building Regulations submission. We deliver calculations and reports to clients anywhere in the UK, and arrange any site visit by region.
What we check.
The points our calculations resolve for a project like this.
- Complete load path from roof to foundations set at design stage
- Foundation type chosen from soil, trees, slope and site investigation
- Ground floor design to suit the foundation and fill
- Steel and timber sizing for open-plan spans and large glazed openings
- Lateral stability and wind bracing for the whole house
- Coordination with the architect's layout and elevations
From enquiry to sign-off.
Enquiry
Send drawings or describe the problem. We confirm the scope, the deliverables and a target timescale.
Information
We agree the survey, drawings or data we need and any site access required.
Engineering
Design, calculation or assessment to the relevant Eurocodes and UK National Annex.
Issue
A clear, defensible report or set of calculations, with assumptions and limitations stated.
Common questions
Do I need a structural engineer to build a new house?
Yes. A new build needs designed foundations, a designed superstructure and lateral stability, all of which Building Control assesses against Approved Document A. We prepare the full calculation and drawing package for the Building Regulations submission.
How much does structural design for a new build house cost?
For a typical one-off house our fee starts for the foundation and superstructure calculations and drawings, agreed as a fixed price once we have seen the plans. The scale and complexity of the house set the final figure.
When should I bring the engineer in?
As early as possible, ideally alongside the architect. Deciding the load path and stability before the layout is fixed avoids compromises later, such as a loadbearing wall landing where you wanted open-plan space.
Do I need a ground investigation first?
It helps a great deal. Trial holes or a soil report let us design the foundation to the real ground rather than a cautious assumption, which usually saves money on the foundation itself.
Can you design a timber frame or a masonry house?
Both. We design traditional masonry cavity walls, timber frame and hybrid structures, and coordinate with a frame supplier's design where you use a kit.
Related in new build & development structural engineering.
Tell us what you are building.
Send the drawings or describe the project. We confirm scope, deliverables and a realistic timescale.
Start a project