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 Blackheath 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
- SE3 and SE13
- Location
- 6 miles south-east of London
- Pricing region
- London
What do extensions for extra rooms in Blackheath involve?
- Ensuite drainage and extraction
- Heating, insulation and glazing
- Foundations, structure and roof
- Planning route check and drawings
- Fire separation and detection extended to the new space
Which rules apply in Blackheath?
Extensions for extra rooms in Blackheath 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.
- 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 Blackheath?
| 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 Blackheath 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 Blackheath landlords need it?
Typical reasons for this work in Blackheath:
- Moving to more sharers with consent
- A kitchen too small for the number of sharers
Questions about extensions for extra rooms in Blackheath
Can I extend an HMO under permitted development?
Some extensions to houses are permitted development, but rules differ for HMOs and by nation and council. We check the address before design.
How far do you travel from Blackheath?
We cover the whole of Greater London and work UK-wide. For Blackheath the nearest towns on our list are Greenwich (1 miles), Catford (2 miles), Eltham (2 miles).
Does a shared house in Blackheath 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 Blackheath?
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 Blackheath
- Greenwich · 1 mi
- Catford · 2 mi
- Eltham · 2 mi
- Canary Wharf · 3 mi
- Peckham · 3 mi
- Canning Town · 3 mi
- All of Greater London
Other HMO services in Blackheath
- Loft conversions for extra rooms in Blackheath
- Communal kitchen refits in Blackheath
- Layout changes and room reconfiguration in Blackheath
- Large HMO conversions (7+ sharers) in Blackheath
- Ensuite installation in Blackheath
- House to HMO conversion in Blackheath
- Bedroom upgrades and room refits in Blackheath
- EPC and energy upgrades in Blackheath