Architectural Services — Design & Planning Drawings for Your Project

For most home extensions, loft conversions and internal remodels you do not need an ARB-registered architect — a qualified architectural designer or technologist can produce the same planning and building-regulations drawings to the same standards and typically saves 20–40%. "Architect" is a legally protected title, so only ARB-registered professionals may use it, but the title isn't required to design an extension. A full architect adds most value on complex, contemporary, listed or high-value projects. We match you with both and are transparent about each professional's qualifications so you can choose on merit.

In 2026, planning drawings typically cost £1,200–£2,500, full plans (planning plus building-regs drawings) £2,500–£5,000, and a full architectural service £4,000–£12,000+ — often quoted as 7–15% of the build cost. Structural calculations, a measured survey, the planning application fee (around £258 for a householder application in England) and any party-wall agreement are charged separately. Using an architectural designer or technologist rather than a full architect usually cuts design fees by 20–40%. See our architect cost guide for a full breakdown.

An architect is ARB-registered (and often RIBA Chartered) after 7+ years of training — the protected title — and leads on design and complex projects. An architectural technologist is a CIAT member specialising in the technical design, detailing and Building Regulations side of a project. An architectural designer is an experienced designer or draughtsperson; "designer" is not a protected title, so check their portfolio and experience. All three can produce compliant drawings and planning submissions — the right choice depends on your project's complexity and your budget.

No — there's no legal requirement to use an architect for a house extension. For a standard single- or double-storey extension, a qualified architectural designer or technologist can prepare your planning and building-regulations drawings and manage the application, usually for 20–40% less than a full architect. An architect is worth considering if you want a bold contemporary design, the site is difficult, or the property is listed or in a conservation area. Tell us about your project and we'll match you with the right professionals to compare.

Planning drawings show what you want to build — scaled existing and proposed plans, elevations and a site/location plan — enough for the council to assess the application. Building-regulations drawings show how it will be built to comply with the Building Regulations: structure, insulation, drainage, fire safety, ventilation and construction details for your builder and Building Control. Many homeowners commission both as a "full plans" package, but you can buy planning drawings first and add building-regs drawings once planning is approved.

Concept design and a measured survey typically take 2–4 weeks. Preparing planning drawings adds another 2–4 weeks, after which the local authority has a statutory 8 weeks to decide a householder application (often quicker). Building-regulations drawings can be produced in parallel or once planning is granted. Allow roughly 3–6 months from first appointing a designer to having approvals and detailed drawings ready for your builder to price and start.

Not always. Many single-storey extensions, loft conversions and garage conversions fall under Permitted Development and don't need a planning application — though you may want a Lawful Development Certificate to confirm it. Larger extensions, double-storey work, dormers that raise the ridge, new builds and changes of use usually need a householder or full planning application. Listed buildings need Listed Building Consent, and conservation areas and Article 4 zones remove some PD rights. Your designer or architect will advise on the correct route and handle the submission.

The householder planning application fee in England is around £258 in 2026, paid directly to your local authority. A full planning application for a new dwelling, or applications for flats and larger schemes, costs more. This council fee is separate from your design fees, and other costs — a measured survey, structural calculations and any party-wall agreement — are also charged separately. Your designer or architect will tell you which fees apply to your specific project.

Usually not. Architectural fees typically cover the design and drawings, while a measured survey of your property, structural engineer's calculations (needed for beams, steels and openings), the planning fee and any party-wall surveyor's costs are charged separately. A designer or architect can arrange these for you or you can appoint them yourself. Always ask each professional exactly what their quote includes so you can compare like with like — this is one area where quotes often differ.

No. BestBuilders is a free comparison platform — we don't design your project ourselves. We vet architects and architectural designers and connect you with up to three local professionals suited to your project and budget. You compare their quotes, choose who to appoint and contract with them directly. We make the introduction; the design work is delivered by the professional you choose. Using the service is free with no obligation to proceed.

Yes. A full architectural service runs from concept design through planning and building regs to tender drawings (to get accurate builder quotes), contract administration and site inspections to completion. This is typically quoted as 7–15% of the build cost. If you'd rather keep costs down, you can commission just the design and drawings and manage the build yourself, or use a designer for the drawings and appoint your builder separately. Tell us how much help you want and we'll match you accordingly.

Just fill in the quick form on this page — tell us your project type, the stage of service you need and your postcode. It takes about 60 seconds. We'll match you with up to three vetted local architects and architectural designers and you'll usually receive your first quotes within 24 hours. Comparing quotes is free with no obligation to proceed. You can also find local architects and designers directly.