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No room to extend sideways? Describe your loft in a few clicks and get a free, no-obligation quote from a loft conversion specialist in Portsmouth.
Height is the first thing a specialist looks at. Measure the house's internal width and the height from the top of the ceiling joists to the underside of the ridge, then use the sliders to see how much floor area is usable.
The drawing takes 25 cm off the height for a new floor and insulation, and treats the roof as a plain pitched one. Chimney breasts, purlins and the roof shape change the real figures, so a specialist measures on site. The person is 1.75 m tall.
The roof shape and the height of the roof space decide which one fits.
Roof windows installed on the current slope. The least costly and least intrusive option, provided there's enough existing height.
Best on: Homes with roof spaces already tall enough that don't require much extra flooring. Check first: Height of the ridge, chimney breasts, and potential stair positioning.A box extension rising from the rear slope, adding space and headroom. Commonly chosen for terraces.
Best on: Terraced and semi-detached homes needing a full-height space at the rear. Check first: If it qualifies as permitted development and how it appears to those next door.The sloped side of a hipped roof is extended into a straight wall, creating space for stairs and a bigger floor.
Best on: End-of-terrace, semi-detached, and detached houses with hipped roofs. Check first: Party wall regulations and the appearance of the side wall from the road.The rear slope is reconstructed to be nearly vertical with a flat top, providing maximum space, often requiring planning permission.
Best on: Terraces where maximising floor area is crucial. Check first: Planning permission and how it looks when viewed from the street.Six steps, in this order. Planning and party wall paperwork can run alongside the drawings.
Check the height, assess the rafters, chimney breasts, and where a staircase might fit.
Architectural plans and structural calculations for the steel beams and new flooring.
Check on planning requirements or obtain a lawful development certificate if classed as permitted development. Serve party wall notices if sharing a wall.
Submit an application or building notice, with inspections during construction.
First the steelwork and flooring, then the roof structure, stairs, insulation, electrics, and plastering. On-site work takes only weeks.
A completion certificate from building control. Keep it safe, as future buyers' solicitors will need it.
A loft conversion touches the structure of the house and the walls you share. These are the answers worth having in writing.
Most of Portsmouth sits on Portsea Island, where Victorian and Edwardian terraces stand close together, especially in Southsea, North End and Fratton. Parts of Southsea are conservation areas. Portsmouth City Council is the planning authority. Type your postcode in the quote form to check yours.
Many loft conversions are done under permitted development: the added roof space must not exceed 40 cubic metres on a terraced house or 50 on a semi-detached or detached house. The roof must not exceed the existing ridge height, and no extensions can protrude beyond the front slope. Flats, conservation areas, and already extended homes have different rules. Contact Portsmouth City Council about your area.
Yes. Any new room in the roof must comply with regulations on structure, stairs, fire safety, insulation, ventilation, and electrics, regardless of whether planning permission is required. The inspector provides final approval.
If you share a wall with a neighbour, as in terraces or semi-detached homes, and the work affects it, like when steel beams are supported by it, you must serve notice under the Party Wall etc. Act. Your builder or architect can manage the notices.
A dormer conversion typically takes a few weeks on site. However, the design, planning, and approvals must be completed beforehand, so start from the initial survey instead of the scaffolding date.
A typical starting point is around 2.2 metres from the top of the ceiling joists to the underside of the ridge. The new floor and insulation will reduce this height, and stairs require headroom too.
The conversion type, structural work, stairs, windows, insulation, electrics, plastering, fees for the architect, engineer, building control, and party wall surveyors, VAT, payment stages, and exclusions.