Covering Hemel Hempstead
Hemel Hempstead is about 5 miles west of St Albans. We also cover Berkhamsted (5 miles to the west), St Albans and Harpenden.
Homes in the East of England
Across the East of England, newer estates often have integral garages and room for rear extensions, while older towns have Victorian terraces and conservation areas that shape what can be built.
What is an upward extension?
An upward extension adds a new storey on top of an existing house, most often turning a bungalow into a two-storey or chalet-style home. It can double the floor area without using any of the garden.
- Roof removal and temporary weather protection
- New first-floor structure, walls and roof
- Full fit-out of the new rooms
What will an upward extension cost?
Typical ranges for bungalow and upward extensions. Ground conditions, access and specification move the final figure, which we fix in writing before work starts.
| Bungalow and upward extensions | Guide price incl. VAT |
|---|---|
| Chalet conversion with dormers (total) | £45,000 to £85,000 |
| New first floor, standard specification | £2,200 to £2,800 per m² |
| New first floor, good specification | £2,800 to £3,300 per m² |
| New first floor, high specification | £3,300 to £3,800 per m² |
What approvals does an upward extension need in England?
In England we deal with the council’s planning team for permission or a lawful development certificate, with building control (the council or a registered building control approver) for inspections, and with neighbours under the Party Wall etc. Act 1996 where it applies.
In England, Class AA permitted development allows an extra storey on many detached and semi-detached houses built between July 1948 and October 2018, subject to a prior approval application covering design, neighbours’ amenity and other matters.
What should I think about before starting?
- The house is exposed while the roof is off, so the sequence is planned tightly.
- Neighbours’ light and privacy are the main planning tests.
From first call to completion
- Start with a conversation. A short call or the online form is enough for us to understand what you want to build.
- Survey at your house. We look at the existing structure, services and access, and agree what the design needs to achieve.
- Drawings, approvals, written quote. We prepare the design, apply for the approvals it needs, and give you a fixed price in writing.
- Build and hand over. Our teams build to the programme, building control inspects, and you get the completion paperwork at the end.
What people ask before starting
How much does it cost to add a storey?
Around £2,200 to £3,800 per square metre of new floor including VAT, or £45,000 to £85,000 for a chalet conversion with dormers.
Is an upward extension permitted development?
In England, Class AA allows it on many post-1948 houses through a prior approval application. Elsewhere planning permission is needed.
Who deals with the council for a project in Hemel Hempstead?
We do. We prepare the drawings, submit planning or permitted development paperwork if needed, and arrange building control inspections.
Bungalow and upward extensions near Hemel Hempstead
- Bungalow and upward extensions in Berkhamsted
- Bungalow and upward extensions in St Albans
- Bungalow and upward extensions in Harpenden
- Bungalow and upward extensions in Watford
Learn more about bungalow and upward extensions, or see every project we cover in Hemel Hempstead.

