Loft and garage conversions

A loft conversion buys you a bedroom without losing any garden, and on most Mid Sussex housing stock it is the cheapest square metre you will ever add. The question is always whether your roof will take one, and that is settled with a tape measure before anything else gets discussed.

Will your loft convert?

Measure from the top of the ceiling joist to the underside of the ridge. You want around 2.2 metres. Get that and the rest is detail. Fall short and you are looking at a dormer, a roof change, or lowering the ceilings below, all of which are possible and all of which cost more.

Roof construction matters as much as height. Older houses tend to have cut roofs, built up on site from rafters and purlins, and those convert readily. Houses built from roughly the mid-1960s onwards often have trussed rafters, with W-shaped webs filling the loft. Those can still be converted, but the trusses are structural and cannot simply be cut out, so the floor and roof have to be supported another way first. It is a bigger job, not an impossible one.

The types

Rooflight conversion. No change to the roof shape, just insulation, a new floor, stairs and rooflights. The cheapest option, and it needs the head height to already be there.

Dormer. A box built out from the rear roof slope, creating full head height across a good part of the room. The most common conversion we build, and usually permitted development at the rear.

Hip to gable. Where a hipped roof end is built up square, then usually combined with a rear dormer. Common on semi-detached and end-terrace houses.

Regulations, and the two that catch people out

Most rear dormers fall under permitted development, subject to volume limits and to nothing being built above the existing ridge line. Front-facing dormers usually need an application, as does anything in a conservation area.

Two requirements surprise people more than any others. The staircase needs Building Regulations-compliant head height, and finding somewhere to land it without ruining the floor below is often the hardest part of the design. Fire escape and protection also apply: a loft makes a house three storeys, which means a protected stair route, fire doors on the rooms opening onto it, and mains-wired interlinked alarms.

A loft conversion needs Building Regulations sign-off whether or not it needs planning. Without the completion certificate the room cannot legally be called a bedroom, and your solicitor will ask for it when you sell.

What we do

Survey and measure, structural and architectural drawings, the applications, then the build: steels, floor, dormer or roof alteration, staircase, insulation, glazing, electrics, plumbing, plastering and decoration. Certificates and guarantees handed over in one file at the end.