BEFORE YOU START

Plan ahead

Twoofthe most important considerations are ‘potential planning restrictions, and the head height you have to work with’, says Harriet Phillips of Lorne Lofts. ‘Building regulations require a minimum head height of 2.2m within the loft space.’

Size matters

For most loft conversions, planning permission is not required – unless it is larger than the size permitted (40 cubic metres for a terraced house)orina conservation area. If you want to use it as a bedroom, you’ll need to comply with building regulations.

Do your homework

Don’t be put off if you live in a conservation area. ‘Loft extensions are still possible, but you need to design within the restrictions for each area and then apply for planning permission,’ says Phillips.

Get certified

Even if you don’t need planning permission, it’s a good idea – though not a legal requirement – to obtain a Certificate of Lawfulness, according to Phillips, as ‘it can be useful documentation when selling a property’.

Tread carefully

Don’t forget to plan the staircase design. ‘It is a fundamental part of the loft. There are many building regulations to adhere to, plus the staircase positioning will often determine the possible layout options in a loft extension,’ Phillips says.

Safety first

Finally, any extension must adhere to UK building fire regulations. This includes one or a combination of the following to be installed: mains-wired smoke detectors throughout the house, a sprinkler system, a mist system and/or fire-rated doors.

When Helena Rivera, director of the architectural practice A Small Studio (asmallstudio. co.uk), was charged with designing a haven for parents of a growing family, she immediately looked to the roof. ‘They needed a refuge where they could escape after a long day’s work,’ she says.

The house was a four-bedroom home in Dulwich, south London, with an ornate period front and an apex-shaped ground- and first-floor extension at the rear. The clients didn’t want a box extension, so Rivera mimicked the lower extension with three apex-shaped dormers ‘that would accentuate the Victorian geometry, but in entirely different materials’.

It wasn’t easy. ‘The dormers, which have full-height glazing, are only 250mm apart, so the construction was challenging,’ says Rivera. But the effect is stunning and encourages a clean, minimal interior. The three black powder-coated windows frame views over London and provide natural definition to the interior spaces – an open-plan bedroom, bathroom and dressing room – without the need for internal walls. The house went from having 20 square metres of unconverted loft space to a habitable area of 52 square metres.

The three dormer windows demarcate the open-plan spaces of bathroom, bedroom and dressing room