An HMO extension adds space to a shared house, usually a ground-floor bedroom with ensuite or a bigger communal kitchen. For a house in Richmond we start with a measured survey, check the council’s written HMO standards for the number of sharers, and then price each item separately.
- Area
- Greater London, England
- Postcodes
- TW9 and TW10
- Location
- 8 miles south-west of London
- Pricing region
- London
What do extensions for extra rooms in Richmond involve?
- Kitchen or bedroom fit-out
- Fire separation and detection extended to the new space
- Planning route check and drawings
- Building control completion
- Foundations, structure and roof
Which rules apply in Richmond?
Extensions for extra rooms in Richmond must satisfy national law for England, the council’s written HMO standards and, where walls, drainage or fire separation change, the building rules. In short:
- 3–6 unrelated sharers is use class C4; changing from a family house is usually permitted development unless an Article 4 direction applies.
- Building regulations cover structural changes, new partitions, ensuite drainage, fire-resisting construction and notifiable electrical work.
- The Fire Safety Order 2005 applies to the common parts of HMOs, enforced by the fire and rescue authority.
- Council standards often step up at 5 and 6 sharers, for example a separate WC at 5 and a second bathroom from 6.
How much do extensions for extra rooms cost in Richmond?
| Item | UK typical | Local guide | Per |
|---|---|---|---|
| Single-storey extension, about 15 m² | £35,000 – £60,000 | £44,800 – £76,800 | project |
| Single-storey extension per m² | £1,800 – £4,000 | £2,300 – £5,100 | m² |
These are typical ranges including VAT, adjusted for London, where costs run above the UK average. The fixed price for a house in Richmond follows a site visit.
How long does it take?
Most jobs of this kind take 8–14 weeks. If a council deadline applies in Richmond, tell us at the first call so the programme is built around it.
When do Richmond landlords need it?
Typical reasons for this work in Richmond:
- Adding a ground-floor room
- Moving to more sharers with consent
Questions about extensions for extra rooms in Richmond
Will the extension affect neighbours?
Possibly, if it is on or near a boundary. Party wall procedures may apply in England and Wales.
Which postcodes in Richmond do you work in?
All of them, including TW9 and TW10, and the surrounding parts of Greater London.
Where do I check the HMO rules for an address in Richmond?
With the local council for the address. Councils in England can add additional licensing and Article 4 directions on top of the national rules. Check the council’s website for the exact address before you buy or start work.
How much do extensions for extra rooms cost in Richmond?
Our guide ranges for London are in the table on this page, and the guide-price tool gives a figure for your house. A fixed written quote follows a free site visit.
Extensions for extra rooms near Richmond
- Isleworth · 2 mi
- Hounslow · 2 mi
- Barnes · 3 mi
- Chiswick · 3 mi
- Heston · 3 mi
- Acton · 4 mi
- All of Greater London
Other HMO services in Richmond
- Loft conversions for extra rooms in Richmond
- Communal kitchen refits in Richmond
- Layout changes and room reconfiguration in Richmond
- Large HMO conversions (7+ sharers) in Richmond
- Ensuite installation in Richmond
- House to HMO conversion in Richmond
- Fire doors in Richmond
- Rewires and EICR remedials in Richmond