Single Storey Extension Design Services
Ground Floor Space, Done Right. Sussex & Surrey.
Why Sussex Homeowners Trust ArchEvolve With Single Storey Extensions
- 15 years of experience
- 350 planning approvals secured
- 500 projects completed
- Revit 3D modelling as standard
- MCIAT-chartered accreditation
Posted on Google Jonathan GilbertTrustindex verifies that the original source of the review is Google. I would highly recommend Alex and his company. He has amazing suggestions as well as taking into account our preferences and ideas too. He is easily accessible and has been so helpful in answering all our many questions! Looking forward to seeing our vision come to life!Posted on Google James RileyTrustindex verifies that the original source of the review is Google. Alex was really helpful throughout the whole process. This was our first ever project like this and he was on hand to answer MANY questions!Posted on Google Nick RutterTrustindex verifies that the original source of the review is Google. Alex was so helpful from start to finish, great communication throughout. Would strongly recommend and will definitely use their services again in the future!Posted on Google arron tullyTrustindex verifies that the original source of the review is Google. Alex at Arch Evolve assisted with obtaining planning permission for a couple of extensions that we were intending on doing. Very professional and offered allot of very helpful advice. Very Happy Thank you.Posted on Google Marcus EatonTrustindex verifies that the original source of the review is Google. I have worked with Alex on many projects over the years and he has always been brilliant! Looking forward to working together again soon. Very professional and smooth process throughout the whole process.Posted on Google Charlotte MorleyTrustindex verifies that the original source of the review is Google. Archevolve has completed a number of plans for us due to changing my mind regularly. They have been consistently patient & listened to my requirements at all time. Alex has then been on hand for our builders if required. Fantastic company & highly recommendedPosted on Google Peter ProtoTrustindex verifies that the original source of the review is Google. Used Alex for our large project, loft conversion, side garage and rear extension. Unbelievable service from start to finish. We are over the moon with the finish. Thank you so much!!Posted on Google Tony MaioTrustindex verifies that the original source of the review is Google. Great service, they had an excellent understanding of my requirements. They applied great attention to detail, with a fast and very efficient service together very reasonable costs. I highly recommend this firm.
Single Storey Extensions Alongside Related Services
Single Storey Extensions: Getting Permitted Development Right
Common challenges
- Confusion over permitted development size limits
- Designs that create a dark, boxed-in kitchen or living space
- Roof and drainage details missed until construction
- Neighbour consultation scheme requirements overlooked
- Poor integration between old and new roof lines
- Quotes that do not include Building Regulations
How ArchEvolve solves them
- Permitted development assessed accurately before design starts
- Rooflights and glazing positioned for maximum natural light
- Roof and drainage detailing resolved at concept stage
- Neighbour consultation handled as part of the planning process
- Fixed-scope fees covering design through to Building Regulations
- Fixed-scope fees covering design through to Building Regulations
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 Single Storey Extensions in Sussex and Surrey
3D Visualisations Included
Every single 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 single storey extension timeline on track.
Local Planning Knowledge
ArchEvolve has submitted single 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 single storey extension project personally. No handoffs, no junior staff taking over mid-project.
Single Storey Extension Design Across Sussex and Surrey
Many single storey rear extensions fall under permitted development rights, subject to size limits that vary for detached, semi-detached and terraced properties. Side extensions and extensions on designated land, such as conservation areas, usually need full planning permission. ArchEvolve confirms your specific position at the free initial consultation.
Limits depend on your property type and whether a neighbour consultation scheme applies for larger single storey rear extensions. Our guide to how far you can extend without planning permission sets out the current thresholds in detail.
Costs depend on floor area, specification and groundworks. See our house extension cost guide for typical ranges, or get in touch for a fixed-scope design fee quote.
If the extension meets permitted development criteria, a full planning application is not required, although a Lawful Development Certificate is recommended to confirm this in writing. ArchEvolve prepares this alongside the design where appropriate.
The service covers feasibility and permitted development assessment, 3D concept design, planning or Lawful Development Certificate application, full Building Regulations drawings, and construction drawings for your builder.
This is one of the most common reasons for objections and refusals. ArchEvolve designs single storey extensions with roof pitch, window placement and boundary distances considered from the outset to minimise the risk of neighbour objections affecting your timeline.
ArchEvolve covers West Sussex, East Sussex and Surrey, including Worthing, Horsham, Chichester, Crawley, Guildford and Brighton, with a free initial consultation offered to all homeowners in the region.
Frequently Asked Questions
Start Your Single Storey Extension Design Today