
Professional House Extension Solutions for Forest Hill Residents
Planning a house extension in Forest Hill? Our expert architectural team specializes in creating beautiful, functional extensions that enhance your home's value and living space. Located within the Enfield catchment area, Forest Hill offers excellent opportunities for residential development, and our local expertise ensures your project benefits from professional design solutions tailored to the area's unique characteristics.

A recent extension project in the Lewisham area
Our Forest Hill expertise is built on years of successful project delivery across the Enfield catchment area. We understand the local context, from conservation considerations to development opportunities, helping you make informed decisions about your house extension project. Our established relationships with local authorities and contractors ensure smooth project progression from initial design through to completion.
Navigating planning requirements in Forest Hill requires local expertise and up-to-date knowledge of Enfield Council's policies. Our architects understand the specific requirements for extensions in the area and can guide you through the planning application process, ensuring your proposal has the best chance of approval. We provide advice on design considerations, sustainability requirements, and community consultation processes.
Forest Hill has a diverse housing stock and we have experience extending all property types in the area. Our architects adapt designs to suit the character and structure of each home, whether that means matching original brickwork on a period property or creating a contemporary contrast on a more modern home.
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Covering SE23 & surrounding postcodes
Guide prices for house extensions in the Lewisham area. Every project is different — we provide a detailed, itemised quote after a free site visit.
| Extension Type | Typical Cost |
|---|---|
| Single Storey Rear Extension | £35k – £70k |
| Double Storey Extension | £55k – £120k |
| Side Return Extension | £25k – £50k |
| Wrap-Around Extension | £60k – £130k |
| Loft Conversion (Dormer) | £40k – £65k |
| Kitchen Extension | £30k – £60k |
| Basement Conversion | £80k – £200k |
| Garage Conversion | £15k – £30k |
Prices are guide figures for 2026 based on projects in the Greater London area. PD = Permitted Development (no formal planning application needed in most cases). Actual costs depend on specification, site conditions, and scope.

Professional single storey extension design and planning for ground floor expansions
Typical: 6-12 weeks
Two-storey home extension design maximizing space and value
Typical: 8-16 weeks
Garden-facing extensions creating seamless indoor-outdoor living
Typical: 6-10 weeks
Narrow extensions utilizing side garden space efficiently
Typical: 6-12 weeks
Specialized kitchen and dining space extensions for modern living
Typical: 8-14 weeks
Converting attic space into valuable living areas
Typical: 6-10 weeks
Underground extensions creating additional living space
Typical: 12-20 weeks
Expert guidance through planning applications and permitted development
Typical: 8-16 weeks
Comprehensive extensions combining rear and side elements for maximum space
Typical: 10-18 weeks
Comprehensive whole-house renovation and modernization services
Typical: 12-24 weeks
Expert structural engineering services including underpinning and load-bearing work
Typical: 8-16 weeks
Converting garages into functional living spaces for bedrooms, offices, and studios
Typical: 4-8 weeksFrom the first phone call to moving into your new space — here is what to expect at every stage.
We visit your Forest Hill property, discuss your vision, assess feasibility, and give you honest guidance on costs and planning routes.
Our architects create detailed plans, 3D visuals, and construction drawings tailored to your Forest Hill home and how you want to live in it.
We prepare and submit your planning application, liaise with the local authority covering Forest Hill, and handle building regulations documentation.
Our vetted builders bring the design to life. We oversee the build, conduct regular site visits, and manage quality at every stage.
Final inspections, building control sign-off, snagging checks, and handover — your new Forest Hill space is ready to enjoy.
Specializing in residential extensions across Forest Hill, we provide tailored design solutions for every type of project. Our services include architectural design, planning applications, building regulations compliance, and construction drawings. We work closely with homeowners to create extensions that enhance their living space while maintaining the character and value of their property.
Our Forest Hill planning permission services include pre-application advice, full planning applications, and advice on permitted development rights. We work closely with Enfield Council to ensure your application meets all requirements and has the best chance of approval. Our goal is to secure planning permission efficiently while ensuring your project meets all regulatory requirements.

Extension completed in the Lewisham area
Building control compliance is essential for all construction projects in Forest Hill. Our team provides comprehensive building control drawings and applications, ensuring your project meets all structural, fire safety, and accessibility requirements. We work closely with building control officers to ensure smooth approval processes and compliance with current building regulations.
With years of experience working across the Enfield area, our Forest Hill team combines creative design skills with practical project management, ensuring your project is delivered on time and within budget. We understand the unique challenges and opportunities presented by extensions in the area and can provide expert advice on the most appropriate design approach for your specific requirements.

Everything you need to know about loft conversions in London in 2026. Dormer, hip-to-gable, mansard and L-shaped options explained with costs, timelines and planning permission guidance.

Plan your dream kitchen extension in London. Explore side-return, rear and wrap-around options with 2026 costs, planning tips and design inspiration for every budget.

Updated 2026 price guide for house extensions across London. Costs for single storey, double storey, loft conversions and more — broken down by area and project type.
Ready to start your house extension project in Forest Hill? Contact our expert team today for a free consultation and detailed project assessment. We offer competitive rates, professional service, and local expertise that ensures your project's success. Our Forest Hill extension services are designed to meet your specific needs, whether you're planning a rear extension, loft conversion, or complete home transformation.
Discover our comprehensive range of house extension solutions in London and surrounding areas
Professional single storey extension design and planning for ground floor expansions
Two-storey home extension design maximizing space and value
Garden-facing extensions creating seamless indoor-outdoor living
Narrow extensions utilizing side garden space efficiently
Specialized kitchen and dining space extensions for modern living
Converting attic space into valuable living areas
Call now to speak with our expert team. Get instant responses and professional guidance for your extension project.