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 Mitcham 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
- CR4, SM4 and SW19
- Location
- 8 miles south of London
- Pricing region
- London
What do extensions for extra rooms in Mitcham involve?
- Building control completion
- Ensuite drainage and extraction
- Foundations, structure and roof
- Fire separation and detection extended to the new space
- Heating, insulation and glazing
Which rules apply in Mitcham?
Extensions for extra rooms in Mitcham 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.
- Fire precautions follow a risk assessment; the LACORS Housing – Fire Safety guide (2008) is guidance, not law, but many councils base their standards on it.
- National rules ask for an adequate number of bathrooms, WCs and basins and suitably located kitchens; numeric ratios are set by each council.
How much do extensions for extra rooms cost in Mitcham?
| 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 Mitcham 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 Mitcham landlords need it?
We usually get the call when:
- Moving to more sharers with consent
- Adding a ground-floor room
Questions about extensions for extra rooms in Mitcham
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 Mitcham do you work in?
All of them, including CR4, SM4 and SW19, and the surrounding parts of Greater London.
Does a shared house in Mitcham 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 Mitcham?
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 Mitcham
- Morden · 1 mi
- Wimbledon · 2 mi
- Streatham · 2 mi
- Carshalton · 2 mi
- Wallington · 3 mi
- Croydon · 3 mi
- All of Greater London