An HMO extension adds space to a shared house, usually a ground-floor bedroom with ensuite or a bigger communal kitchen. Landlords in Barnes (SW13) usually come to us with a council letter, a fire risk assessment or a house they have just bought. We price from whichever you have.
- Area
- Greater London, England
- Postcodes
- SW13
- Location
- 6 miles south-west of London
- Pricing region
- London
What do extensions for extra rooms in Barnes involve?
- Heating, insulation and glazing
- Ensuite drainage and extraction
- Kitchen or bedroom fit-out
- Foundations, structure and roof
- Party wall coordination where needed
Which rules apply in Barnes?
Extensions for extra rooms in Barnes 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.
- A conversion can be a material change of use under the building regulations, so confirm with building control before work starts.
- Smoke alarms on every storey with living accommodation and CO alarms by fixed combustion appliances (other than gas cookers) are required by law.
- 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 Barnes?
| 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 Barnes follows a site visit.
How long does it take?
Typical time on site: 8–14 weeks. We agree the programme with you before starting and send photo updates as the work progresses.
When do Barnes landlords need it?
Landlords in Barnes most often ask us for this when:
- A kitchen too small for the number of sharers
- Adding a ground-floor room
Questions about extensions for extra rooms in Barnes
Is a kitchen extension worth it?
Often, when the existing kitchen limits how many people the council will allow. A bigger kitchen can unlock an extra room.
Do you cover all of Barnes?
Yes. We work across Barnes and the SW13 postcode areas, plus the rest of Greater London. Nearby places we also cover include Chiswick, Putney, Fulham.
Does a shared house in Barnes need an HMO licence?
In England, a mandatory licence is needed for 5 or more people from 2 or more households. Smaller HMOs can need a licence where the council runs additional licensing, which is common in towns with many shared houses. Check the council’s website for the address.
How much do extensions for extra rooms cost in Barnes?
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 Barnes
- Chiswick · 1 mi
- Putney · 2 mi
- Fulham · 2 mi
- Shepherds Bush · 2 mi
- Richmond · 3 mi
- Acton · 3 mi
- All of Greater London
Other HMO services in Barnes
- Loft conversions for extra rooms in Barnes
- Communal kitchen refits in Barnes
- Layout changes and room reconfiguration in Barnes
- Large HMO conversions (7+ sharers) in Barnes
- Ensuite installation in Barnes
- House to HMO conversion in Barnes
- Full HMO refurbishment in Barnes
- Licence condition and schedule-of-works in Barnes