Where the council wants a sympathetic look, conservation rooflights fit the brief: slender steel frames with one glazing bar, lying close to the tiles. It reads like the old iron rooflights that lit lofts and stores in town buildings, and a number of them open on a hinge. A tall building like this may gain from two small units instead of one large one, spaced so that air can cross between them.
Outshuts, yards and the back of the building
Almost every old house in a market town has something tacked on behind: a scullery, a washhouse, a later kitchen. These outshuts have low roofs and tiny windows, and the rooms inside are often the darkest in the building. A small rooflight over a lean-to turns such a room around, and if it opens, cooking steam no longer hangs about. Because they sit out of sight, they are among the easiest roofs to improve.
Shopfronts add one more wrinkle. A flat above a shop may have its own roof, a different owner and no right to alter anything, and that changes who can say yes. Flats and maisonettes are outside the usual permitted rights for houses, so a rooflight for an upstairs flat often means asking the freeholder and the council both. Sort that before you fall in love with a design.
It pays to know what is underneath. Timbers in an old roof are never evenly spaced, and a lath-and-plaster ceiling underneath needs care when it is opened. Our visit includes a look at the structure from the loft before we propose a size. Taking out one whole rooflight to fit another brings in Building Control, and the regulations guide shows how.
Ground-floor shop premises with a flat above have a particular problem in summer. The top flat has no cool floor beneath it and a roof taking the full sun, so a bedroom under the slope can reach an uncomfortable level by late afternoon. A well-placed opening window, even a small one, lets the day's heat leave once the sun drops, and the night air does the rest.
The best arrangement in a tall old house is simple. Air should arrive low, from a front sash or the yard, and depart high, through a window the warm air can reach. Fit a unit that opens over the upper stair, leave a ground-floor window ajar, and air starts to travel through every floor.