Covering Harpenden
We work in Harpenden (AL5) and the places around it, including St Albans, Luton and Hemel Hempstead.
Homes in the East of England
The East of England has a large stock of post-war and modern estate housing alongside period homes in market towns, which makes garage conversions, single-storey extensions and loft conversions popular.
What is included in a garden annexe in Harpenden?
A garden annexe is a separate single-storey building in the grounds of a house with its own bedroom, bathroom and kitchenette, used by family members as part of the main household. Unlike a garden office, an annexe that people sleep in normally needs planning permission and full building regulations approval.
- Foundations and drainage connections
- Kitchenette and shower room
- Heating, hot water and electrics
How much should I budget for a garden annexe?
Indicative costs for garden annexes. London and the South East usually sit towards the top of each range.
| Garden annexes | Guide price incl. VAT |
|---|---|
| Standard specification | £2,400 to £2,900 per m² |
| Good specification | £2,900 to £3,400 per m² |
| High specification | £3,400 to £3,900 per m² |
Planning and building rules in Harpenden
English projects need planning clearance from the local council, building regulations sign-off from building control, and party wall notices where the work is on or near a shared boundary. We prepare and manage all three.
A self-contained annexe used for sleeping and living normally needs planning permission in England.
What can change the price or programme?
- The annexe normally has to remain part of the main household, not let as a separate home.
- A level threshold and wider doors make the annexe suitable for later life.
What happens after I enquire?
- Start with a conversation. A short call or the online form is enough for us to understand what you want to build.
- Free site visit. We measure up, look at access, drains and the structure, and talk through options and budget.
- Drawings, approvals, written quote. We prepare the design, apply for the approvals it needs, and give you a fixed price in writing.
- We build it. Work follows an agreed programme, with inspections at each stage and a final sign-off.
What people ask before starting
Do I need planning permission for a garden annexe?
Usually yes, because people will sleep in it. Outbuilding permitted development does not cover living accommodation.
How long does an annexe take to build?
About 14 to 24 weeks on site after approvals.
Can you visit a house in Harpenden to quote?
Yes. After a short call we arrange a site visit to measure up and agree what the design needs to do, then send a written price.
Also covering
- Garden annexes in St Albans
- Garden annexes in Luton
- Garden annexes in Hemel Hempstead
- Garden annexes in Welwyn Garden City
Learn more about garden annexes, or see every project we cover in Harpenden.