Extending a Listed Building: What's Possible and What's Not?

An approved Glazed Link and Dual Barns to a Grade II Listed Dwelling in South Oxfrodshire, currently under construction.

With Grade Listed Buildings, one of the questions I'm asked most often, usually within the first five minutes of a phone call, is some version of: ‘Can we even touch it?’… Owning a listed building comes with a particular kind of anxiety. People love the character of their home, but they're often convinced that any change… a new window, an extra bedroom, a kitchen extension… is somehow off-limits. It rarely is. It just has to be done properly, with the right architect and the right approach to Listed Building Consent.

A recent project in South Oxfordshire is a good example. Our clients had bought a Grade II listed farmhouse with a cramped, single-storey 1970s kitchen extension tacked onto the rear… itself not original, and not particularly sympathetic to the house. They wanted more space, more light, and a kitchen that actually worked for a family of five, but they were nervous about starting a fight with the conservation officer before they'd even had their morning coffee.

What Is Listed Building Consent?

Listed Building Consent (LBC) isn't really about whether you're allowed to extend a listed building. It's about whether the proposed work would harm the "special architectural or historic interest" of the property. In practice, that means the conservation officer is looking closely at:

• Which parts of the building are original and which have been altered over the years (a 1970s extension carries far less weight than the Georgian front elevation it's attached to).

• Whether new work is clearly subordinate to the historic fabric, in scale, position, and materials.

• Whether the change is reversible. Extensions and alterations that could, in theory, be removed in future without damaging historic fabric are looked on far more favourably than ones that aren't.

• Internal features as much as external ones… fireplaces, staircases, panelling, and joinery can all carry listing significance, even in rooms that look unremarkable at first glance.

Case Study: Extending a Listed Farmhouse in South Oxfordshire

Because the existing rear extension had no historic value, removing it was straightforward to justify. The harder conversation was about what replaced it. We designed a new single-storey kitchen and garden room in brick and oak-framed glazing, deliberately set back from the corners of the original house and finished in a contrasting but complementary palette, so that from the garden it reads clearly as a modern addition rather than a pastiche extension pretending to be old.

We also did the legwork before submitting: an early conversation with the conservation officer, a heritage statement explaining the significance of each part of the building and why our approach respected it, and photographs showing exactly what was original and what wasn't. Consent was granted without amendments, which is rarer than you'd think.

Common Mistakes Homeowners Make With Listed Building Extensions

• Assuming the whole building is equally protected. It isn't… significance varies room by room, sometimes wall by wall.

• Thinking "matching" is always the safest design approach. Conservation officers often prefer an honest, well-detailed contrast over a poor copy of historic detailing.

• Leaving the heritage statement as an afterthought. A clear, well-argued statement is often what turns a borderline application into an approved one.

• Forgetting that internal alterations need consent too, not just the visible exterior changes.

FAQs: Extending a Listed Building

Do I need planning permission as well as Listed Building Consent? Often, yes. Most extensions to listed buildings need both Listed Building Consent and full planning permission, since they're assessed against different policy tests.

Can I make internal changes without consent? No. Internal alterations to a listed building… removing a wall, replacing a staircase, even some redecoration in significant rooms… can require Listed Building Consent even if nothing changes on the outside.

How long does Listed Building Consent take? Most local authorities aim to determine applications within 8 weeks, though more sensitive heritage cases can take longer, especially where Historic England is consulted.

Key Takeaways

Listed buildings aren't meant to be frozen in time, and most conservation officers know that better than anyone. The goal isn't to avoid change, it's to make sure any change earns its place. With the right argument and the right detailing, that farmhouse kitchen is now exactly what our clients wanted: bright, modern, and built around a family's daily life, sitting comfortably alongside two hundred years of history next door.

Thinking about extending a listed building in Berkshire, Buckinghamshire, Hampshire, South Oxfordshire, Surrey, or West London? Get in touch to talk through what's possible.

Becoming a RIBA Chartered Practice and What It Means for Our Clients

BLOG POST THREE: Becoming a RIBA Chartered Practice and What It Means for Our Clients

I’m pleased to announce that Pont + Wils Architects is now a RIBA Chartered Practice, marking a milestone after five years of delivering architectural projects across Berkshire, Buckinghamshire, Hampshire, South Oxfordshire, Surrey, and West London. This achievement is more than a recognition of our work; it offers tangible benefits for homeowners and developers seeking a trusted architect for their projects.

Becoming a RIBA Chartered Practice requires meeting the highest standards of professionalism, client care, and competence. It involves ongoing professional development, rigorous quality management, ethical practice, and clear communication. For clients, this guarantees that projects; from the first concept sketch to completion; are handled by qualified, accountable professionals.

In addition, I am registered with the Architects Registration Board (ARB), the statutory regulator for architects in the UK. Only ARB-registered architects can legally use the title “architect,” ensuring that clients engage a professional who has the necessary qualifications, professional standards, and insurance.

Working with a RIBA Chartered Practice and ARB-registered architect provides clear advantages:

• Commitment to quality: Projects are designed and delivered to nationally recognised standards.

• Professional accountability: Clear codes of conduct ensure reliable advice, documentation, and decision-making.

• Up-to-date expertise: Continuous professional development keeps our knowledge of planning, sustainability, and building regulations current.

• Better project outcomes: From planning policy to consultant coordination, an architect can prevent costly mistakes and optimise design potential.

• Client protection and transparency: RIBA and ARB frameworks ensure clear appointments, realistic expectations, and transparent fees.

Choosing a RIBA Chartered Practice is about more than a badge—it’s about placing your project in skilled, professional hands, ensuring a smoother, more enjoyable, and successful architectural process.

This milestone reflects the values that have guided Pont + Wils Architects from the start: thoughtful design, careful communication, and a commitment to work that endures.

Pictured above is the old RIBA Chartered Practice Logo in Red and below is the new RIBA Chartered Practice Logo in Black and White.

Navigating Outbuilding Permitted Development: A Recent Project Case Study

BLOG POST TWO - Navigating Outbuilding Permitted Development: A Recent Project Case Study

At Pont + Wils Architects, we often help homeowners in Surrey and the Home Counties create functional garden outbuildings, from home offices and studios to gyms and guest rooms. A recent project in Elmbridge demonstrates how careful permitted development (PD) planning can deliver practical outbuildings while ensuring full compliance with UK planning rules.

Our client wanted a substantial garden outbuilding with a shower room, but no kitchenette. This distinction was key, as the absence of a kitchen meant the structure would not be considered a separate dwelling, keeping it firmly within permitted development rights.

To maximise usable interior space, the outbuilding was positioned over 2 metres from the side boundary, allowing us to design it at full height under PD rules. This approach avoids height restrictions that apply to structures closer to neighbouring boundaries.

During construction, Elmbridge Borough Council were tipped off about the building. I visited the site to meet with the enforcement officer, reviewing the outbuilding against permitted development regulations and our client’s Certificate of Lawful Development for the proposed use. The officer confirmed that the building met all criteria, demonstrating how clear communication with the local authority can prevent enforcement issues.

Permitted Development Rules for Garden Outbuildings

Homeowners should be aware of the following key PD rules in England:

• Single-storey only, with a maximum height of 4 metres for dual-pitched roofs or 3 metres for other roof types.

• Maximum eaves height of 2.5 metres if within 2 metres of a boundary.

• No kitchen allowed, ensuring the building is not treated as a separate dwelling.

• Total footprint must not exceed 50% of the garden (excluding the original house).

By carefully following these guidelines, we delivered a lawful garden outbuilding with a shower room that maximised usability without triggering a full planning application.

This Elmbridge project highlights the importance of permitted development compliance, boundary-aware design, and proactive engagement with the local planning authority. It’s a clear example of how homeowners can achieve functional, stylish, and fully lawful garden outbuildings in Surrey with the right architectural guidance.

Entering Our Fifth Year in Architecture Practice

BLOG POST ONE - Entering Our Fifth Year in Architecture Practice

Starting this journal feels a little like opening a new sketchbook: full of possibility, intention and quiet excitement. Over the past five years of architectural practice, so much of my work has happened behind the scenes, evolving through countless sketches, 3D models, site visits and planning conversations long before a project ever reaches construction. This journal is my way of bringing some of that journey into the open.

At Pont + Wils Architects, our projects across Berkshire, Buckinghamshire, Hampshire, South Oxfordshire, Surrey and West London have continued to grow in scale and variety. From working carefully with listed buildings to designing contemporary extensions, replacement dwellings and small multi-unit schemes, each project carries its own narrative. These are exactly the kinds of architectural services that many homeowners and developers search for, and my aim is for this journal to become a helpful and authentic resource.

Rather than focusing solely on polished finished images, I want to share more of the thinking behind our work. This will hopefully include:

• how and why certain design decisions are made on certain projects,

• insights from planning applications and listed building consent processes,

• reflections on materials, sustainability and detailing,

• examples of design approaches for extensions and new build homes,

• and the occasional story from site meetings, surveys or early client conversations.

Architecture is about far more than drawings. It is about understanding people, responding to context and creating places that feel considered and enduring. My hope is that this journal will offer future clients, homeowners and curious readers a clearer sense of how we approach design and what it is like to work with an architect.

So here is the first entry. A simple beginning that sets the tone for a collection of thoughts, lessons and experiences gathered over five years of practice.

More to come soon.