St Albans home office extensions, designed and built
A home office extension in St Albans starts with the right design and the right approval route. We take care of both, then build it with our own project management.
- Guide price in St AlbansFrom £16,500 inc VAT
- PlanningOften permitted development (3–4 m), or prior approval up to 6–8 m
- Build time8–12 weeks on site
- Postcode districtsAL1, AL2, AL3, AL4

What we take care of
- Window and rooflight placement to avoid screen glare
- Data cabling and plenty of sockets
- Layout for desk, storage and video calls
- Sound insulation to the adjoining rooms
North-facing glass and rooflights give steadier light for screen work. Where the office faces south, we use deeper reveals or external shading to keep glare and heat down.
Guide prices for St Albans
For St Albans we adjust our national guide rates by ×1.06, the factor we use for East of England. Figures include VAT; your written quote after the survey replaces them.
Typical rates in St Albans: £1,960 to £3,600 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 2.5 m × 3.2 m 8 m² | £16,500 – £20,500 | £18,000 – £23,000 | £22,500 – £29,000 |
| 3 m × 3.6 m 11 m² | £21,500 – £26,000 | £25,000 – £31,500 | £31,000 – £40,000 |
| 3 m × 5 m 15 m² | £29,000 – £35,000 | £34,000 – £43,000 | £42,500 – £54,500 |
Want a range for your exact size? The guide-price tool takes about a minute.
Do I need planning permission in St Albans?
In England a single-storey rear extension can usually go up to 3 m beyond the original rear wall of a semi-detached or terraced house, or 4 m on a detached house, without a planning application, provided it is no more than 4 m high, keeps eaves to 3 m within 2 m of a boundary and, with other buildings, covers no more than half the land around the original house. The larger home extension prior approval scheme raises those depths to 6 m and 8 m, with neighbours notified and a 42-day decision.
In a conservation area, national park, National Landscape, the Broads or a World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.
Building regulations approval is separate from planning. In England you can use the council's building control team or a registered building control approver; a full plans application gets the drawings checked before work starts, and the inspector signs the work off with a completion certificate.
If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.
Applications are decided by the local planning authority (your district, borough or unitary council).
Covering St Albans
Our survey diary covers St Albans, including AL1, AL2, AL3, AL4. Neighbouring towns we cover include Harpenden (5 miles), Hatfield (5 miles), Hemel Hempstead (5 miles), Welwyn Garden City (6 miles).
For homes towards Greater London, Barnet is around 9 miles away. Across the East of England many houses sit on generous plots, and single-storey and wraparound extensions are a natural fit.
From first visit to completion
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
First, a site visit: we look at the house, garden, access and drains and listen to what you need.
Design and approvals
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
Fixed written price
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Common questions in St Albans
Who do I contract with for a home office extension in St Albans?
Your contract is with S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for St Albans, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Do you cover all of St Albans?
Yes. We cover St Albans and the surrounding parts of Hertfordshire. Site visits are free and there is no obligation.
How much does a home office extension cost?
Our guide range is about £1,960 to £3,600 per m² including VAT. An 11 m² standard-spec office is typically £25,000 to £31,500 in St Albans.
Is an attached office better than a garden office?
An attached office shares the house heating and broadband, adds floor area to the home, and needs no garden path in the rain. A garden building can be cheaper and quicker but is a separate structure.
Book a free site visit in St Albans
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.