Wandsworth Architects & Planning Consultants for House Extensions

Planning permission, architectural design and project management  delivered end-to-end by a multi-award-winning local team.

All-in-One Architects: Design, Planning & Building Regulations Under One Fixed Fee

Planning applications handled for Wandsworth — council decisions arrive in 8 weeks standard.
Article 4 Directions affect many SW18 streets — we check PD rights first.
Full design, planning, and building regulations delivered together under one fixed fee.
Loft conversions available — Velux, dormer, and hip-to-gable options all designed in-house.
In-house structural engineer included — no separate specialist needed for your calculations.
A 98% planning approval rate achieved across 80+ completed Wandsworth projects locally.

Extension Architecture handles planning applications, house extensions, and loft conversions across Wandsworth and the wider Wandsworth area, including SW18, SW11, SW17. Some streets keep Permitted Development rights, but Article 4 applies in many areas. Our in-house structural engineer and RIBA-chartered team manage every stage, from survey to completion. Council decisions take 8 weeks. Get your free quote today.

We only deliver excellence

80⁺

Projects completed in Wandsworth

2220 ⁺

Our total projects completed in London & Surrey

Locations in Wandsworth

Wandsworth • Battersea • Putney • Tooting • Balham • Clapham Junction • Earlsfield • Southfields • Roehampton • East Putney • West Hill • Wandsworth Town • Furzedown

Postcodes Served

SW18, SW17, SW15, SW12, SW11

Our Expertise

Planning Application Drawings
Council-ready drawings, fast

3D Visualisations
See it before building

Retrospective Planning
Fix unpermitted works

Building Regulation Drawings
Safe, compliant drawings

Commercial Development Consultancy
Change of use experts

Interior Design
Finishes inside out

Spatial Planning & Layout
Smarter room layouts

Feasibility Consultancy
Know what’s possible

Recent Architects Wandsworth Extension & Loft Conversion Projects

Wandsworth Planning Consultants: Article 4 Directions & Conservation Areas

Wandsworth is of course a desirable place to be, close to the centre of London with a mix of high streets and local parks around the neighbouring areas. The local authority in Wandsworth is rightfully strict about regulations and conservation areas which protect historically and architecturally significant buildings. Even if your property is not located in these designated areas, it doesn’t stop the local authorities from carefully considering the proposed changes. As experienced architects in Wandsworth, we understand Wandsworth planning regulations and can help navigate your project to achieve its objectives and respect the unique heritage of the area.

Victorian terraces dominate SW18 — ideal for rear and loft projects.
Article 4 Directions cover many streets — early planning advice is recommended.
Strong local demand means well-designed extensions consistently add lasting property value.
Wandsworth Council works to a clear 8-week householder planning decision timeline.

Interior fit-out, Wandsworth

What Our Clients Say About
Extension Architecture

Interior fit-out, Wandsworth

Loft Conversion In Wandsworth

Loft conversions are a popular option for Wandsworth homeowners looking to increase the value of their property by adding an extra bedroom or private living area. Wandsworth builders or homeowners have to go through a number of restrictions, particularly if the property is in a conservation area or a listed building.

Planning permission may be required, if the alteration involves major changes to the roof or involves dormer windows. Additionally, building codes must be followed, ensuring safety and construction integrity. By adhering to the code, builders or homeowners can create stunning rooftop or lofts that blend seamlessly with the existing home and meet Wandsworth’s regulations.

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Before & After: Wandsworth House Extension Projects

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Before

After

Why Choose Our Wandsworth Architects?

Our experienced team of Wandsworth architects will take the lead and create a thoughtful design that maximizes the available space and is tailored to your tastes. We will guide you through the intricacies of the planning process and discuss every aspect of the project in detail. Our architects will carefully survey your property to ensure no detail is overlooked. We will be with you throughout the process, providing clear and comprehensive instructions while walking you through the planning, application and construction process.

One-Stop Solution

Our firm provides a comprehensive range of services under one roof, from planning and architectural design to intricate interior and immersive design, and expertly manages the complexities of the construction process. We have delivered projects of various scales and budgets, from small home extensions to large new builds, for a diverse clientele.

In-house Structural Engineer

We have a structural engineer in-house - something most architecture firms don't offer. It matters because juggling separate specialists costs time and money. With a structural engineer on our team, calculations and drawings stay coordinated under one roof, keeping the design-build process smooth and reducing errors.

Interior Design + Architecture

Our team includes interior designers who work closely with every client to curate spaces tailored to their taste and how they live. This covers the enjoyable but important decisions - wall finishes, colour schemes, soft furnishings and flooring. Having Wandsworth architects and interior designers under one roof means fewer gaps and inconsistencies.

Turn-Key Approach

We provide support throughout the entire building process, embracing a ‘turnkey approach’ to ensure a smooth and efficient project from start to finish. Additionally, we assist in reducing build costs by aiding in the procurement of all internal fit-outs, including sanitaryware, kitchens, and more. It’s a zero hassle solution for clients.

Start Planning Your House Extension in Wandsworth Today

Planning a house extension in Wandsworth? Our architects can help you design a space that suits your home, needs and budget.

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Architectural design consultation and home extension planning services

Years of Experience

17

Any Questions?

Didn’t find your answer? Feel free to reach out

In most cases, yes — though it really comes down to which street you’re on. A lot of Wandsworth is covered by Article 4 Directions, which strip away the normal “permitted development” rights that let you build a small rear extension without asking the council first. So if your road falls under Article 4, even a fairly modest single-storey extension needs full planning permission. We’ll check your address against the Article 4 register before you pay us anything or we start any design work — it’s free and takes the guesswork out early.

It sounds more alarming than it is. An Article 4 Direction just means the council has removed the automatic building rights you’d normally get under “permitted development” on certain streets — so instead of building without asking, you need to submit a full planning application. It doesn’t make approval harder, it just means there’s a formal step you can’t skip. Large parts of SW18 and SW11 fall under Article 4 in Wandsworth. As part of our free feasibility check, we’ll tell you straight away whether your house is affected.

Wandsworth Council aims to decide standard householder applications within 8 weeks of validation. If you’re in a conservation area or your design is more complicated, it can stretch to around 13 weeks. Once you get approval, it’s valid for 3 years, so there’s no rush to start building the next day — you’ve got time to sort finances and a builder. We stay on top of every application ourselves and reply to council questions the same day they come in, so things don’t stall waiting on us.

For a single-storey rear extension, build costs generally start somewhere around £2,000–£2,500 per square metre, though the final number depends on the spec you want, how complex the structural work is, and how easy your site is to access. Loft conversions and double-storey extensions are a different cost picture altogether because of the roof and foundation work involved. We’ll give you a free, honest cost estimate as part of the initial feasibility check — before you’ve committed to paying for any design work.

Yes, we’re both RIBA-chartered and ARB-registered, which are the two main professional accreditations architects in the UK are expected to hold. We’ve been running for 17 years now, with over 2,220 completed projects across London and Surrey, including more than 80 in Wandsworth alone. We also keep a structural engineer in-house — something only around 1 in 20 architecture firms in the UK actually do — so you’re not left coordinating between separate consultants.

The biggest one, by far, is assuming permitted development rights apply to your house without actually checking for an Article 4 Direction — find that out too late and it can set your whole project back by months. Beyond that, people often underestimate structural costs by not bringing an engineer in early enough, or submit drawings that don’t take a conservation area’s specific rules into account. A free feasibility check right at the start avoids all three of these.

Wandsworth Architects & Planning Consultants for House Extensions