© Simon Maxwell
Single-storey extensions and some first-floor rooms may have the potential to add a vaulted ceiling if there is a pitched roof loftspace above. The flat ceiling can be removed so that the underside of the rafters becomes the ceiling, creating a dramatic double-height space. Where a room has very tall ceilings there may be scope to add a mezzanine storey and, in some cases, lowering the existing ceiling in a room can create the additional headroom required to make a mezzanine or attic storey in the loft above.
Cost: removing the conventional flat ceiling above a room with a pitched loft space above to create a double-height, vaulted ceiling would cost £2,000 to £3,000. This includes altering wiring for ceiling lighting, adding 140mm-160mm of insulation between and underneath the rafters, plus new plasterboard and skim ceiling to the underside of the rafters. Add £800 to £1,200 if a rooflight is to be added.
Shedding more light
Bring in light from more than one direction. Consider roof lights and high-level windows that overcome any privacy problems on neighbours' boundaries. Replace a whole section of wall with floor-to-ceiling glazing.
Cost: a fixed double-glazed unit measuring 2.6m x 1.5m will cost £600 to £700, and roughly the same again for installation. Glass doors measuring 2.6m high will cost about £4,000 to £6,000 a linear metre.
Use understairs space
Use the space beneath a conventional straight staircase with stud walling for a downstairs cloakroom. Extend existing pipework within the floor or ceiling voids to provide hot and cold plumbing and connect to an existing soil pipe internally, or externally if the staircase is against an external wall. If there is no existing soil pipe within easy reach, a pumped smallbore, flexible soil pipe can be used, with a macerator (saniflo.co.uk).
Cost: forming an understairs cloakroom, including fitting WC (with Saniflo) and basin, plumbing, heated radiator towel rail and lighting, tiling and decorating, costs £3,000 to £4,200, using a small jobbing builder.
Remove the chimneybreast
A redundant chimneybreast, where all connecting fireplaces have been removed, is a waste of space. The whole chimneystack, or alternatively the internal chimneybreast, can be removed and the stack left on the roof, supported by steel brackets.
Cost: removing a chimney will typically cost from £1,500 to £3,000.
Larger properties can be subdivided to create additional rooms. Create an en suite shower room by subdividing part of a bedroom, or enclosing part of a large landing area. A larger bedroom can be subdivided into two smaller children's bedrooms. Non-load bearing stud walls are easily reversible in the future.
Cost: Adding timber-framed partition walls costs £60 a linear metre at a standard ceiling height of 2.4m. Add £150 to £200 for a doorway. Costs exclude adding radiators, power points and light switches.
Upgrade the interiors
Change floor finishes, update doors and windows, lighting and heating, repair and repaint plasterwork and upgrade your kitchen and bathroom. Create the illusion of space with pale colours and mirrors. Take advice from an architect and interior designer.
Get expert advice from Michael Holmes at the National Home Improvement Show (28-30 September). For more information on the show, exhibitors, seminar schedules and tickets visit improveyourhomeshow.co.uk or call the ticket hotline on 0844 581 0802. Tickets are £8 if booked in advance and £12 on door.
THE RULES ARE SIMPLE BUT MUST BE FOLLOWED
Internal alterations to houses do not usually need planning permission unless the building is listed. Most minor alterations to houses — including the conversion of attics, cellars and garages, and adding doors and windows — are classed as permitted development (planningportal.gov.uk).
Flats and maisonettes do not have permitted development rights. Permitted development rights can also be restricted or removed on houses. Check with your local authority before proceeding with any work.
Any work or alterations that affect a neighbouring property, especially flats, terrace houses and semis, will require you to issue a party-wall notice to the owners under the Party Wall Act (England and Wales). For details, visit communities.gov. uk.
DON'T FORGET YOUR LEASE
Alterations to a leasehold property (which means all flats) will require consent from the freeholder.
Almost all new building work, material alterations such as cellar, loft and garage conversions, plus replacement windows, and most new electrical and plumbing work, must comply with the building regulations. The work is notifiable to the local authority, meaning that you must complete the relevant forms and pay a fee.