Covering Wiltshire
We cover Wiltshire, including Swindon, Salisbury, Trowbridge and Chippenham, and the towns around them.
Homes in the South West
In the South West, matching local stone, render or slate is often the main design question, and conservation areas and listed buildings are common in historic towns.
What goes into 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.
- Design and planning or prior approval application
- Staircase and changes to the ground floor layout
- Full fit-out of the new rooms
How much does an upward extension cost in Wiltshire?
Use these ranges to budget for bungalow and upward extensions; the survey turns them into a fixed price for the agreed specification.
| 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 |
Planning and building rules in Wiltshire
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 can change the price or programme?
- Some bungalow foundations need strengthening before a storey can be added.
- The staircase takes space from the ground floor plan.
How does the project run?
- Send us the details. Give us a postcode, a rough idea of size and some photos, by phone, form or the guide price tool.
- We visit and measure. A surveyor checks the house, the boundaries and the ground, and discusses what is realistic.
- Price and paperwork. The design is priced line by line, and we submit the planning and building control applications.
- We build it. Work follows an agreed programme, with inspections at each stage and a final sign-off.
What people ask before starting
Can I add a first floor to my bungalow?
Often yes, if the walls and foundations can carry the load and planning allows. We check the structure first.
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.
Can you visit a house in Wiltshire 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.
Bungalow and upward extensions near Wiltshire
- Bungalow and upward extensions in Swindon
- Bungalow and upward extensions in Salisbury
- Bungalow and upward extensions in Trowbridge
- Bungalow and upward extensions in Chippenham
- Bungalow and upward extensions in Warminster
- Bungalow and upward extensions in Calne
- Bungalow and upward extensions in Devizes
- Bungalow and upward extensions in Corsham
Learn more about bungalow and upward extensions, or see every project we cover in Wiltshire.

