Structural Engineering Services in Staines & Surrey

Expert Calculations, Surveys, and Structural Designs — Delivered with Chartered Experience and Local Knowledge

At Jonathan Darnell Engineering Ltd, we provide specialist structural engineering services for homeowners, developers, and contractors throughout Staines-upon-Thames and Surrey. With over 40 years of industry experience, our work ensures safety, compliance, and buildability — from concept to construction.

We specialise in structural design and calculations for house extensions, loft conversions, wall removals, foundations, commercial builds, and more. All services include expert consultation, regulation-compliant documentation, and personal support from a chartered engineer.

Structural drawings

Structural Calculations & Design

Accurate, Regulation-Ready Calculations for Any Build

We provide structural calculations for steel beams (RSJs), timber joists, concrete slabs, and other key elements required by Building Control. Whether you’re removing a wall or constructing a new home, our calculations ensure strength, stability, and compliance.

Fast Turnaround • Building Control Approved • Delivered in 3–7 Days

Loft conversion with dormer

Structural Surveys & Reports

Clear Advice for Property Buyers, Owners & Builders

We inspect and report on visible cracks, movement, subsidence, and other issues affecting structural safety. Our reports are suitable for mortgage approval, insurance, or project planning.

Detailed Reports • Site Visits Available • Trusted Local Insight

Close architectural floor plans desk with hands holding pen ruler.

Loft Conversion Engineering

Turn Roof Space into Living Space — With Confidence

We provide structural support and layouts for dormer, Velux, and hip-to-gable loft conversions. Our service includes all required calculations, ridge beams, joists, and load transfer checks.

Compliant, Safe Loft Conversions for Every Property Type

Steel beam

Foundations & Retaining Wall Design

Groundwork That Holds Strong

We design safe, compliant substructures for new builds, extensions, and retaining systems. Every design accounts for load paths, soil types, and structural requirements.

Engineered to Last • Fully Calculated • Site-Specific Solutions

Let’s Get Your Structure Right — First Time

Contact Jonathan Darnell today for structural calculations, inspections, or design support.

Scroll to Top