In short: An HMO extension adds space to a shared house, usually a ground-floor bedroom with ensuite or a bigger communal kitchen. We carry this out across Pembrokeshire, priced against the HMO rules for Wales and the council’s own standards.
- Nation
- Wales
- Pricing region
- Wales
- Postcode areas
- SA
- Main towns
- Haverfordwest, Milford Haven
What do extensions for extra rooms in Pembrokeshire involve?
- Fire separation and detection extended to the new space
- Building control completion
- Heating, insulation and glazing
- Ensuite drainage and extraction
- Foundations, structure and roof
- Planning route check and drawings
Which rules apply in Pembrokeshire?
- More than 6 sharers is a sui generis HMO and needs planning permission; councils such as Cardiff apply concentration limits.
- Building regulations cover structural work, partitions, drainage, fire-resisting construction and electrics; confirm with building control whether the conversion is a material change of use.
- Fitness for human habitation rules require mains-powered, interlinked smoke alarms on every storey and CO alarms where there is a gas, oil or solid-fuel appliance.
- Kitchen and bathroom ratios are set in each council’s HMO standards.
- Council HMO standards and the fire risk assessment set detection, fire doors and escape routes.
Welsh councils set their own HMO standards and may run additional licensing. In Wales, changing a house to a C4 HMO always needs planning permission, so check planning first.
How much do extensions for extra rooms cost in Pembrokeshire?
| Item | UK typical | Local guide | Per |
|---|---|---|---|
| Single-storey extension, about 15 m² | £35,000 – £60,000 | £32,900 – £56,400 | project |
| Single-storey extension per m² | £1,800 – £4,000 | £1,700 – £3,750 | 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 Pembrokeshire
Questions about extensions for extra rooms in Pembrokeshire
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.
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 carry out extensions for extra rooms across Pembrokeshire?
Yes, across the whole of Pembrokeshire, including Haverfordwest, Milford Haven.
Who licenses HMOs in Pembrokeshire?
Pembrokeshire council licenses HMOs in its area. Landlords must also register with Rent Smart Wales.
Other HMO services in Pembrokeshire
- Loft conversions for extra rooms in Pembrokeshire
- Communal kitchen refits in Pembrokeshire
- Layout changes and room reconfiguration in Pembrokeshire
- Large HMO conversions (7+ sharers) in Pembrokeshire
- Ensuite installation in Pembrokeshire
- House to HMO conversion in Pembrokeshire
- Student HMO refurbishment in Pembrokeshire
- Rewires and EICR remedials in Pembrokeshire