In short: An HMO extension adds space to a shared house, usually a ground-floor bedroom with ensuite or a bigger communal kitchen. Across Northamptonshire, the work is planned around England’s HMO rules and the standards the local council publishes.
- Nation
- England
- Pricing region
- East Midlands
- Postcode areas
- NN, PE, OX, LE
- Main towns
- Northampton, Corby, Kettering, Wellingborough, Rushden
What do extensions for extra rooms in Northamptonshire involve?
- Heating, insulation and glazing
- Planning route check and drawings
- Building control completion
- Kitchen or bedroom fit-out
- Fire separation and detection extended to the new space
- Foundations, structure and roof
Which rules apply in Northamptonshire?
- 7 or more sharers is a sui generis large HMO and normally needs planning permission.
- 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.
- A conversion can be a material change of use under the building regulations, so confirm with building control before work starts.
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 Northamptonshire?
| Item | UK typical | Local guide | Per |
|---|---|---|---|
| Single-storey extension, about 15 m² | £35,000 – £60,000 | £33,950 – £58,200 | project |
| Single-storey extension per m² | £1,800 – £4,000 | £1,750 – £3,900 | m² |
Typical time on site: 8–14 weeks. For a figure for your house, try the guide-price tool.
Extensions for extra rooms by town in Northamptonshire
Questions about extensions for extra rooms in Northamptonshire
Do you handle building control?
Yes, from application to completion certificate.
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.
Do you carry out extensions for extra rooms across Northamptonshire?
Yes, across the whole of Northamptonshire, including Northampton, Corby, Kettering.
Who licenses HMOs in Northamptonshire?
HMOs in Northamptonshire are licensed by the local council for the address. Where an area has several councils, each runs its own licensing and planning policies.
Other HMO services in Northamptonshire
- Loft conversions for extra rooms in Northamptonshire
- Communal kitchen refits in Northamptonshire
- Layout changes and room reconfiguration in Northamptonshire
- Large HMO conversions (7+ sharers) in Northamptonshire
- Ensuite installation in Northamptonshire
- House to HMO conversion in Northamptonshire
- Sound insulation in Northamptonshire
- Escape routes, emergency lighting and fire stopping in Northamptonshire