Do I Need an Architect for a Refurbishment? London Guide 2026

You need an architect when your refurbishment involves significant design: extensions, reconfiguring the layout, planning applications or work to a listed building. For a like-for-like refurbishment, redecoration, a new kitchen or bathroom in the same footprint, or replacing services, a competent contractor and, where structure is altered, a structural engineer are usually all you need. The deciding question is not the size of the budget but whether you are changing the shape and use of the space. This guide sets out exactly which route fits which project, and what each one costs.

When do you actually need an architect?

An architect earns their fee when a project needs design thinking, not just construction. There are four situations where we would always recommend one. First, extensions and any change to the building's footprint or roofline. Designing a rear or side-return extension, a loft conversion with dormers, or anything that alters the external envelope benefits from an architect's spatial design and their handling of the planning system. Second, layout reconfiguration. If you are moving multiple walls, relocating kitchens and bathrooms, changing how rooms flow into one another or reorganising a whole floor, an architect's drawings turn a vague idea into a coordinated, buildable plan. Third, planning applications. Where consent is required, professionally prepared drawings and a designer who understands local policy materially improve your chances and save time. Fourth, listed buildings and conservation areas. These carry strict controls, and an architect or heritage specialist who can navigate listed building consent is close to essential; getting it wrong here is a criminal offence, not just a planning refusal.

When a good contractor and engineer are enough

Many London refurbishments do not need an architect at all, and paying for one would add cost without adding value. If you are refurbishing like-for-like, keeping the existing layout and replacing tired elements, an experienced contractor can plan and deliver the whole job. This covers full redecoration, new flooring throughout, rewiring and replumbing, replastering and a new heating system. Kitchens and bathrooms in the same position are firmly in this category. A kitchen designer or the supplier handles the layout within the room, and the contractor coordinates the trades; an architect adds nothing to a same-footprint kitchen. Where the only structural change is straightforward, removing a single non-load-bearing wall, or knocking through with a beam designed by a structural engineer, you do not need an architect to manage it. The contractor builds to the engineer's calculations and the building control inspector signs it off. The dividing line is simple: if you are changing the look and the services but not the shape or use of the space, a good contractor is the right lead, not an architect.

Project type	Architect needed?
Redecoration and new flooring	No
New kitchen or bathroom, same footprint	No
Full rewire, replumb, replaster	No
Removing one wall with a structural engineer's beam	No (engineer, not architect)
Reconfiguring the layout of a floor	Usually yes
Rear or side-return extension	Yes
Loft conversion with dormers	Yes
Planning application required	Yes
Listed building or conservation area works	Yes (or heritage specialist)

The role of a structural engineer

The professional most refurbishments actually need is not an architect but a structural engineer, and the two roles are often confused. An architect designs space, how it looks, how it functions and how it sits within planning policy. A structural engineer makes that space stand up. Whenever you remove or alter anything that carries load, you need engineer's calculations: the size and grade of a steel beam (RSJ) for a knock-through, the padstones or spreader plates it bears on, the support for a removed chimney breast, or the lintel over a new opening. For a simple like-for-like refurbishment with one structural opening, you can often go straight to a structural engineer and skip the architect entirely. The engineer produces calculations and a simple drawing, the contractor builds to them, and building control inspects and signs off. Engineer's fees for a single beam are modest, typically £400–£900 for calculations on a straightforward opening, far less than full architectural design. Knowing which professional you need stops you overpaying for design you will not use.

Building control applies either way

Whichever route you take, building control is a separate, non-negotiable step for structural and notifiable work, and it is easy to overlook. Building control checks that the work complies with the Building Regulations, structural safety, fire safety, insulation, drainage, ventilation and electrical safety. It applies whether an architect designed the scheme or a contractor and engineer planned it between them. Removing a load-bearing wall, altering the structure, forming new openings, certain electrical work and new drainage all need building control sign-off. You access it through either your local authority building control or a private approved inspector, on a full plans or a building notice basis. The contractor typically coordinates inspections at the key stages, foundations, beams and structural openings, drainage, and completion, and you receive a completion certificate at the end. That certificate matters well beyond the build. It is the document a buyer's solicitor asks for when you sell, and unsigned structural work, like a missing party wall award, can stall a sale. Cosmetic refurbishment, redecoration, like-for-like kitchens and bathrooms, flooring, generally does not need building control, which is another reason a same-footprint refurb is so much simpler to deliver.

How design-and-build works

Design-and-build is the route that suits most homeowners who want a single point of responsibility, and it is how we prefer to work on refurbishment projects. Under this model, one contractor takes responsibility for both the design coordination and the construction. Where design input is needed, the contractor brings in the structural engineer (and, for more complex schemes, an architect) and coordinates them, so you are not managing three separate professionals who each blame the others when something does not line up. The advantage is accountability. With separate appointments, the classic problem is the gap between the architect's drawing and what is buildable on site, where responsibility falls through the cracks. Design-and-build closes that gap because the people drawing it and the people building it answer to the same contract. It also tends to be faster and more cost-certain, because buildability is considered from the first sketch rather than discovered on site. For straightforward refurbishments and modest structural work, design-and-build with a competent contractor and a structural engineer is usually the most efficient route. For ambitious architectural schemes, a separately appointed architect leading the design still has its place, the right structure depends on how much design the project genuinely demands.

What each route costs

Cost is where the architect question becomes concrete, and the figures vary widely with the route you choose. A full architectural service, from initial design through planning and detailed drawings to overseeing construction, typically costs 7–15% of the construction budget. On a £150,000 refurbishment that is £10,500–£22,500. For an extension or a complex reconfiguration, that fee buys design quality and planning expertise that genuinely pays for itself. A structural engineer for a single opening costs far less, roughly £400–£900 for calculations on a straightforward beam, with more complex multi-beam schemes running £900–£2,500. For a like-for-like refurbishment with one knock-through, this may be the only design fee you incur. Building control fees are separate and modest by comparison, commonly £400–£1,000 for domestic work depending on scope and authority. Party wall surveyor fees, where shared walls are affected, add £700–£1,500 per neighbour. The right route is the cheapest one that still delivers your project safely and compliantly: an architect for design-led work, an engineer and a good contractor for everything else.

Service	Typical cost
Full architectural service	7–15% of construction budget
Structural engineer (single opening)	£400 – £900
Structural engineer (multi-beam scheme)	£900 – £2,500
Building control (domestic)	£400 – £1,000
Party wall surveyor (per neighbour)	£700 – £1,500

Frequently Asked Questions

Do I need an architect to remove a wall and open up a kitchen?

Usually no. To remove a single load-bearing wall and install a beam, you need a structural engineer for the calculations and a competent contractor to build to them, with building control signing off the structural work. An architect only becomes necessary if you are also reconfiguring the wider layout, extending, or making a planning application as part of the same project.

What is the difference between an architect and a structural engineer?

An architect designs space, how it looks, functions and fits within planning policy, and prepares the drawings for planning and construction. A structural engineer ensures that space is structurally safe, calculating beams, lintels and supports for any work that affects load. Many refurbishments need only an engineer; the architect is for design-led work such as extensions, reconfigurations and planning applications.

How much does an architect cost for a London refurbishment?

A full architectural service typically costs 7–15% of the construction budget, so £10,500–£22,500 on a £150,000 project. Limited-scope appointments, drawings for planning only, for example, cost less. By comparison, a structural engineer for a single opening is roughly £400–£900, which is why a like-for-like refurbishment with one knock-through often needs no architect at all.

Do I need building control if I don't use an architect?

Yes. Building control is independent of whether an architect is involved. Any structural alteration, new opening, certain electrical work and new drainage need building control sign-off regardless of who designed the scheme. Your contractor typically arranges inspections at key stages and obtains the completion certificate, which a buyer's solicitor will ask for when you eventually sell.

Can a builder do a refurbishment without an architect?

For a like-for-like refurbishment, redecoration, same-footprint kitchens and bathrooms, rewiring, replastering and straightforward structural openings, a competent contractor (with a structural engineer where load is affected) can deliver the whole project without an architect. Design-and-build with a single accountable contractor is often the most efficient route. An architect is needed once you move into extensions, layout redesign, planning applications or listed buildings.

Do I Need an Architect for a Refurbishment in London?