Double Storey Extension Design Services
More Floor Area, One Planning Application. Sussex & Surrey.
Why Sussex Homeowners Trust ArchEvolve With Double Storey Extensions
- 15 years of experience
- 350 planning approvals secured
- 500 projects completed
- Revit 3D modelling as standard
- MCIAT-chartered accreditation
Double Storey Extensions Alongside Related Services
Double Storey Extensions: Where Structure Meets Planning
Common challenges
- Massing that overwhelms the existing property or streetscape
- Overlooking objections from first floor windows
- Structural loading issues discovered after planning approval
- Roof tie-in details that create leaks or cold bridging
- Party wall complications with attached and semi-detached properties
- Designers without in-house Building Regulations capability
How ArchEvolve solves them
- Massing and roof form designed to match the existing property
- Window positioning assessed against neighbour overlooking distances
- Structural coordination with an engineer built into the design stage
- Roof and junction detailing resolved before planning submission
- Full Building Regulations package produced in-house
- Full Building Regulations package produced in-house
How an ArchEvolve Project Works
Initial Consultation
Feasibility Assessment
Concept Design
Planning Application
Building Regulations
Construction Drawings
Construction Support
years of experience
Planning approvals
projects completed
largest construction project developed
Proudly Serving Homeowners Across Sussex and Surrey
A Different Standard of Design for Double Storey Extensions in Sussex and Surrey
3D Visualisations Included
Every double storey extension project is modelled in Revit and rendered in Enscape. You see accurate light, materials and spatial quality before a planning application goes in.
Faster Planning Submissions
Drawings produced in a coordinated 3D environment are more complete and less prone to officer queries, which keeps your double storey extension timeline on track.
Local Planning Knowledge
ArchEvolve has submitted double storey extension applications across West Sussex, East Sussex and Surrey planning authorities. Your submission is prepared for the specific council from day one.
End-to-End Service
From feasibility through to construction drawings, Alex Page manages every stage of your double storey extension project personally. No handoffs, no junior staff taking over mid-project.
Double Storey Extension Design Across Sussex and Surrey
Yes, in almost all cases. Double storey extensions fall outside permitted development rights more often than single storey projects, particularly where they affect roof form, overlooking or the character of the property. ArchEvolve confirms your specific requirements at the free initial consultation.
Costs are higher than single storey projects due to structural work, scaffolding and roof alterations. See our house extension cost guide for typical ranges across extension types.
This is the most common reason double storey applications face objections. ArchEvolve positions first floor windows and assesses overlooking distances at concept design stage, before the application is submitted, to reduce the risk of delay.
ArchEvolve coordinates directly with a structural engineer during design so loading, foundations and roof tie-ins are resolved before Building Regulations drawings are produced, rather than discovered during construction.
Planning determination typically takes 8 to 13 weeks depending on your council, with structural coordination and Building Regulations running alongside. Our guide to planning a home extension covers the wider timeline.
Yes, although party wall matters and structural tie-ins with the neighbouring property need careful handling. ArchEvolve has designed double storey extensions across all property types throughout Sussex and Surrey.
ArchEvolve covers West Sussex, East Sussex and Surrey, including Worthing, Horsham, Chichester, Crawley, Guildford and Brighton, with a free initial consultation offered throughout the region.
Frequently Asked Questions
Start Your Double Storey Extension Design Today
