Putting rooflights or skylights in farmhouses and bungalows on Lowton's flat ground

Lowton is a village-sized place sitting in a gap between several larger neighbours, and its houses show what each of them left behind. The oldest buildings are the brick farmhouses and cottages along the lanes, some of them listed, with thick walls, deep eaves and sometimes a pitched roof laid in slate or old clay tile over a lean-to at the back. The farming that gave them their purpose has largely gone, and several outbuildings have been turned into houses.

Coal mining shaped the area around Golborne and Leigh, and the terraced streets built for that workforce reach into the edges of Lowton. They are short brick rows with slate roofs and a flat or lean-to roof over a rear kitchen. Beyond those, the larger part of the village is semi-detached housing from the inter-war and post-war decades, with a smaller number of detached houses and a good many bungalows. The newest layer is estate housing, often with a deep plan and a roof covered in concrete tile.

Lowton Common, Lowton St Mary's and Lane Head each have a slightly different feel on the ground, but for a rooflight the question is rarely the name of the district. It is the roof covering, the pitch and the room beneath. A farmhouse loft with big old timbers asks for a very different approach to a bungalow loft with factory-made trusses, because trusses cannot be cut as freely as hand-sawn rafters, and the opening has to be planned around them.

Many semis in the village have also grown sideways and backwards. Garages become living rooms, kitchens push out into the garden under a new flat roof, and the rooms that result sit far from the old windows, which makes them the darkest in the house. Over such an extension a flat rooflight or small lantern lights the part of the plan that needs it. The roof is already flat and its joists are easy to read, so this is the simplest job we do in the village.

That is the practical difference between the old stock and the new. A roof built from trusses leaves little room for a trimmer in the wrong place, so we measure it first and choose the unit to fit the gaps. A farmhouse can accept a larger opening, but only once a structural check has confirmed what the timbers can carry.

Bungalows are worth a word of their own. Lowton has many from the 1960s and 70s, with a shallow pitch and a hipped end, and the loft above is often boarded already. The ridge height decides how much room can be made up there, and a roof window in the back slope is usually what brings it to life, lighting the boarded space directly from the back slope, with no new wall needed.

Lowton lies within the Wigan borough, so planning decisions are made by Wigan Council, whose website is wigan.gov.uk. For a house here, the permitted development limits on a skylight will normally settle the matter with no application. Flats and maisonettes, houses under an Article 4 direction and listed buildings sit outside that.

Listing is the one to watch. Along the lanes, plenty of farmhouses, cottages and barns could carry a listing. However small the opening, a listed building needs consent before any rooflight goes in; how consent works for a listed rooflight explains the process. We do not guess which houses carry a listing; the council or Historic England can tell you, and a quick check before the survey saves everyone time.

We tell Wigan Council's building control service about each Lowton job before the cutting starts. The Building Regulations guide covers what the inspector looks for on a new rooflight.

The roof of a converted bungalow may also solve the escape question for the room. Because a bungalow loft sits within 4.5m of the ground, a roof window that meets the Approved Document B sizes can be the way out. Full figures are in the escape-window sizes for a loft room.