A study with a view of the sky
Answer a few questions about the job. It's free and there is no obligation.
Need one more room but not a new address? Answer a few questions about your loft and get a free, no-obligation quote from a loft conversion specialist in Northampton.
Many loft conversions don't require a planning application, but some do. Select what applies to your house to find the likely route, then confirm with the council.
Type of house
Volume allowance for the added roof space: 50 cubic metres.
General guidance for houses in England. Rules change and depend on your property, so check with West Northamptonshire Council. This is not legal or planning advice.
The shape of the roof decides the options. This shows what is common on each type of house, as a guide and not a promise.
Swipe sideways to see all four conversion types.
| House | Rooflights | Rear dormer | Hip-to-gable | Mansard |
|---|---|---|---|---|
| Mid-terrace | Often | Often | Rarely | Sometimes |
| End of terrace | Often | Often | Sometimes | Sometimes |
| Semi-detached | Often | Often | Often | Sometimes |
| Detached | Often | Often | Sometimes | Rarely |
| Flat or maisonette | Permitted development rights do not cover flats, so a conversion needs planning permission and the freeholder's agreement. | |||
Roof windows fitted into the current slope. The most affordable and least intrusive, provided there's adequate height already.
A box extension that rises from the rear slope, adding floor space and headroom. Commonly chosen for terraces.
The sloping side of a hipped roof is modified into a vertical wall, creating space for a staircase and larger floor area.
The rear slope is rebuilt almost vertically with a flat top, providing maximum space, and usually requires planning permission.
Six steps, in this order. Planning and party wall paperwork can run alongside the drawings.
A loft conversion touches the structure of the house and the walls you share. These are the answers worth having in writing.
Northampton grew as a boot and shoe town, and rows of Victorian and Edwardian terraces still run through the streets around the centre, with interwar and postwar estates further out. Planning is handled by West Northamptonshire Council. Type your postcode in the quote form to check yours.
Many lofts are done under permitted development: the roof space added must not exceed 40 cubic metres for a terraced house or 50 for a semi-detached or detached one, the roof cannot be higher than the existing one, and nothing can extend beyond the front slope. Different rules apply to flats, conservation areas, and previously extended houses. Contact West Northamptonshire Council for details about your street.
Yes. Any new room in the roof must comply with rules on structure, stairs, fire escape, insulation, ventilation, and electrics, regardless of planning permission. The inspector signs it off upon completion.
If you share a wall with a neighbour, as in a terrace or semi, and the work affects it, such as when steel beams rest on it, the Party Wall etc. Act requires you to serve notice first. Your builder or architect can handle these notices.
On site, a dormer conversion usually takes a few weeks. However, the design, drawings, and approvals come first and add time, so start planning from the initial survey rather than the day the scaffolding goes up.
A typical starting point is around 2.2 metres from the top of the ceiling joists to the underside of the ridge beam. Some height is lost to the new floor and insulation, and the stairs need headroom too.
The type of conversion, structural work, stairs, windows, insulation, electrics, plastering, fees for the architect, engineer, building control, and party wall surveyors, VAT, payment stages, and exclusions.