Extension & loft conversion (Sevenoaks, Kent)
The structural calculations behind this project, prepared by our engineers for building control.
Project Overview
Location
Sevenoaks, Kent
Project Type
Extension & loft conversion
Structural Services
Detailed Calculations
Compliance
Building Regulations
Extension & Loft Conversion – Sevenoaks, Kent
This Sevenoaks home has been expertly transformed with a rear extension and loft conversion, creating additional living space, enhanced functionality, and increased property value. The homeowners wanted to expand their ground floor for a larger kitchen and living area, while also maximising their loft space to add an extra bedroom and en-suite.
To ensure structural integrity, stability, and full compliance with Building Control, PorthouseDean provided expert structural calculations, supporting the structural framework, steel beam reinforcements, and load-bearing wall modifications for a safe and efficient build.
Maximising Space & Light with Smart Structural Design
This project included:
✅ A rear extension – Expanding the ground floor with an open-plan kitchen and living area
✅ A loft conversion – Creating additional bedroom space with a dormer extension
✅ Structural steelwork & RSJs – Supporting wide openings for a modern, open-plan feel
✅ Large bi-fold doors & skylights – Enhancing natural light and garden connectivity
What we did
Our contributions included:
✔ Structural calculations for the extension & loft conversion – Ensuring safety and compliance
✔ RSJ beam & steel design – Supporting large-span openings and load distribution
✔ Load-bearing wall assessments – Safely modifying existing structures
✔ Roof and floor reinforcements – Strengthening the loft for long-term durability
With expert structural engineering, this Sevenoaks home now benefits from a bright, modern, and highly functional extension and loft conversion, perfect for family living and entertaining.
Thinking About a Home Extension or Loft Conversion? Let’s Make It Happen!
At PorthouseDean, we provide expert structural calculations for home extensions, loft conversions, RSJs, and open-plan renovations.
📍 Providing structural engineering across Sevenoaks, Tonbridge, and Kent.
Why Extend Your Home?
More Space, More Possibilities
Create an open-plan kitchen, a family hub, or a bright entertaining space.
A Date You Can Plan Around
You choose the delivery date, and the price follows the date.
More Natural Light
A wider opening to the garden needs a beam sized for the load above it. The calculations set that size.
Personalised Design
Every house is built differently. The calculations work from your drawings and the structure you already have.
How PorthouseDean Supports Your Project
Every project is different, but the need for precise, reliable structural calculations remains the same. Our engineers work with:
Homeowners
Ensuring designs are safe, cost-effective, and practical.
Architects
Providing calculations that allow for creative yet compliant designs.
Builders
Making sure construction runs smoothly with clear, reliable specifications.
Planning Your Own Project?
More than 9,000 projects since 2012 have run through the same process. You get a fixed price before you commit, and you choose the delivery date.
📩 Get a QuoteStructural Engineering Services We Offer
Structural Calculations for Loft Conversions
Calculations for the floor, beams and roof changes a loft conversion needs.
Structural Calculations for Wall Knock-Throughs
Beam and support calculations for taking out a wall.
Structural Calculations for Extensions & New Builds
Calculations for foundations, walls, beams and roofs on extensions and new builds.
Structural Calculations for Bi-Fold Doors & RSJs
Beam and padstone sizes for wide openings and bi-fold doors.
Structural Drawings & Building Control Calculations
Complete documentation to help you achieve smooth Building Control approvals.