Double-Storey Extensions in Surrey & Elmbridge
- 30 years experience
- 10-year structural guarantee
- Fixed fee quotation
- 5% Scheduling discount
- 500+ Successful projects
Add space on two floors with a carefully planned double-storey extension that improves both everyday living and long-term family flexibility.
Double-storey extension builders for growing family homes
A double-storey extension can add valuable accommodation on both the ground and first floor. It can create a larger kitchen or living space downstairs while adding bedrooms, bathrooms, a dressing area or a better first-floor layout above.
HWP Design & Build delivers double-storey extensions across Elmbridge, East Molesey, Esher, Weybridge, Cobham and nearby Surrey towns. We coordinate design, planning, structure, foundations, roof integration, drainage, services, Building Regulations, internal refurbishment and finishing.
Two-storey extensions need especially careful planning because they affect scale, neighbours, overlooking, rooflines, foundations and the way both floors connect with the existing home.
Clear scope, fixed-price clarity and local accountability
HWP Design & Build is the trading name of SMA Design & Build Ltd. We combine over 30 years of hands-on industry experience with practical design thinking, insured delivery, tidy site management, quality finishing and aftercare support.
Learn more about our process, accreditations, insurance and guarantees, aftercare and customer reviews.
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Double-Storey Extensions in Surrey & Elmbridge:
HWP Design & Build provides double-storey extension design and construction across Surrey, Elmbridge and nearby South West London. We assess planning risk, foundations, structural load paths, roof integration, drainage, windows, first-floor layout, Building Regulations, access and finish specification before preparing a fixed-price quotation.
What type of double-storey extension is right for your home?
The right option depends on whether the priority is more living space, more bedrooms, a better first-floor layout or a whole-home upgrade.
| Option | Best suited to | Typical benefit |
|---|---|---|
| Two-storey side extension | Homes with suitable side space and scope to improve both floors. | Can add ground-floor space plus a bedroom, bathroom or home office above. |
| Two-storey rear extension | Homes where the rear elevation can be extended proportionately. | Improves garden-facing living space and first-floor accommodation. |
| Double-storey kitchen and bedroom extension | Growing families needing practical space downstairs and more rooms upstairs. | Balances daily living space with long-term family flexibility. |
| Double-storey extension with refurbishment | Homes where existing rooms also need reworking. | Creates a more consistent whole-home layout and finish. |
| Planning-led double-storey extension | Sites with neighbour, conservation or scale sensitivity. | Develops a proportionate proposal around local planning expectations. |
Planning permission, permitted development and local design context
Double-storey extensions often need planning permission, especially where they affect side elevations, neighbouring amenity, overlooking, roof form or the scale of the original house. Some may fall under permitted development only where strict limits and conditions are met, so early planning review is important.
We can review whether your project is likely to need planning permission, whether a lawful development certificate is sensible, and how the design should respond to local expectations in Elmbridge, Surrey and nearby South West London.
- Permitted development checks for size, height, depth, boundary position and materials.
- Householder planning applications where the proposal exceeds permitted development limits.
- Conservation area, neighbour, daylight, overlooking and street-scene sensitivity reviews.
- Coordination between drawings, structural information, specification and build scope.
How much does a double-storey extension cost in Surrey?
Double-storey extension cost depends on footprint, foundations, structure, roof integration, scaffolding, windows, bathrooms, services, internal refurbishment, planning requirements and finish specification. We avoid misleading headline prices because each property, scope and specification is different.
Once we understand the property and project brief, we prepare a clearer quotation based on real site conditions, drawings, specification, approvals and finish expectations.
| Cost factor | Why it affects the quotation |
|---|---|
| Foundations and structure | Two floors add more load, so foundation depth, steelwork and structural design are critical. |
| Roof and external matching | Roof integration, brickwork, tiles, windows and external detailing affect both cost and appearance. |
| First-floor layout | Bedrooms, bathrooms, landings and stair relationships need careful design. |
| Services and drainage | Bathrooms, heating, electrics and plumbing routes across both floors influence cost. |
| Scaffolding and access | Two-storey work requires more access planning, weather protection and site logistics. |
| Internal making good | Connecting old and new rooms across two floors can add significant refurbishment scope. |
For broader budget planning, read our Surrey house extension cost guide or our Elmbridge house extension costs, planning and timeline guide.
Our double-storey extension process
We use a clear process so design, approvals, pricing and construction remain joined up from the start.
What happens after you request a double-storey extension quotation?
We review your enquiry, arrange a suitable time to discuss the property, then assess layout, access, structure, planning route, Building Regulations, likely disruption and the level of finish required before preparing a clear scope.
Start your extension enquiryLocal extension considerations in Elmbridge and Surrey
Extension projects around East Molesey, Esher, Thames Ditton, Kingston, Surbiton, Walton-on-Thames, Weybridge and Cobham often involve established housing stock, neighbouring boundaries, drainage routes, mature trees, conservation sensitivity and restricted access. We review these points early so the design, quotation and programme reflect the real property.
| Area | Common consideration | How we approach it |
|---|---|---|
| East Molesey / West Molesey | Family homes, rear gardens, shared boundaries and KT8 planning context. | Early checks around access, drainage, party wall position, garden connection and buildability. |
| Hampton Court / Thames Ditton | Character homes, river-adjacent settings, conservation sensitivity and proportionate extensions. | Designs are tested for scale, materials, roof form, local character and site logistics. |
| Esher / Claygate | Larger family homes, specification-led projects and premium finish expectations. | Clear feasibility, design coordination and specification-led pricing before construction. |
| Kingston / Surbiton | Victorian, Edwardian and terrace-style homes with layout and party wall constraints. | Practical design around structure, services, neighbours, drainage and sequencing. |
| Walton-on-Thames / Weybridge / Cobham | Detached and semi-detached homes with scope for larger extensions and whole-home upgrades. | We coordinate design, specification, structural requirements and build programme as one managed route. |
Double-Storey Extensions in Surrey & Elmbridge across Elmbridge, Surrey and South West London
We are based near the Surrey and London border and regularly support homeowners planning extensions, loft conversions, refurbishments and full home improvements across the local area.
Key locations include East Molesey, West Molesey, Hampton Court, Thames Ditton, Esher, Claygate, Walton-on-Thames, Weybridge, Cobham, Kingston upon Thames, Surbiton, Teddington, Twickenham, Richmond and Wimbledon and nearby South West London.
Recent house extension project inspiration
Explore recent projects to see how different extension types, planning constraints, structural requirements and internal layouts can be approached.
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Useful house extension guides
Related house extension services
Planning a house extension? These related services help with approvals, structure, project coordination and wider home improvement work.
Double-Storey Extension FAQs for Surrey & Elmbridge Homeowners
Often yes, but it depends on the property, position, scale and design. We assess the planning route early and can coordinate applications where required.
It is usually more involved than a single-storey extension, but careful phasing, weather protection, access planning and communication help keep disruption manageable.
Yes. We aim for a cohesive external finish by considering brickwork, roof tiles, windows, proportions, eaves, ridge lines and detailing.
Not always. Many clients stay in the home, but this depends on the extent of structural work, service interruptions and affected rooms.
We define the drawings, structure, specification, approvals and site constraints before pricing, so the quotation is based on a clearer scope.
Yes, where the property and budget support it. We can advise on sequencing, structure, planning and Building Regulations so the works are coordinated.
Two-storey extensions for living space, bedrooms and bathrooms.
Ready to price your double-storey extension?
Whether you want more ground-floor living space, extra bedrooms, a new bathroom or a full two-floor transformation, we can assess your property, explain the planning route and provide fixed-price clarity before work begins.
Double-Storey Extensions in Surrey & Elmbridge across East Molesey, Elmbridge, Surrey and nearby South West London.