Roofers in Backwell

The parish church of St Andrew has been altered and enlarged repeatedly: in the 13th, 15th, 16th and 17th centuries, after its 12th-century beginnings. The church is listed Grade I, the top category, and its tower rises past 100 feet. For anyone who owns a house in its shadow, the church is a useful reference. It shows that old buildings are not fixed objects but a series of repairs and additions, each made for a reason and each leaving a join.

Houses near the church share this pattern at a smaller scale. An older cottage may have a main range, a later rear wing, and a lean-to added when a family grew. Each has its own roof, joined to the next by a valley, a flashing or a shared wall. When water gets in, it nearly always comes in at one of those joins.

We trace a leak from the stain back along the timbers, because water often travels several feet along a rafter or a wall plate before it drips. A brown patch beside a chimney breast may begin at a flashing on the far side of the stack, and a damp corner may come from a valley two metres away. This is slow, careful work, and it is why we survey from both inside the loft and outside on the roof.

If a building is listed, the roof falls within the listing, and the first step for any change is North Somerset Council, the local planning authority. Where a house simply sits in an older part of the village, the question is one of matching: a covering that reads correctly alongside its neighbours and uses the same material and colour as the one it replaces.

Once we know the cause, we tell you what we found, show the photographs, and set out a repair that deals with that cause and no more.

Many households look for extra space inside the home they already have, and the loft is often the easiest place to find it. A loft room involves the roof in three ways: it may need a roof window or rooflight for light and escape, it needs insulation to a modern standard, and it needs a safe way out in a fire.

Building Regulations apply to all three. For escape, a roof window passes as an exit only on a storey whose floor lies at most 4.5 m up, which leaves a loft room over two storeys relying on a protected stair. Insulation falls under Part L of the Regulations, which sets limits for new roof windows and rooflights, and the table below gives the figures that apply to existing dwellings.

Whether a new roof window needs planning permission is a separate question with its own conditions. Planning and fitting are dealt with under skylights and roof windows.

The leak risk with a roof window is almost always in the surround. A flashing kit is designed to shed water round the frame, and it depends on the tiles or slates being cut and dressed neatly to it. A window set into a roof that has since been re-covered, or fitted with the wrong kit for the covering, will leak at the corner first. We check the flashing, the lead at the top and sides, and whether the underlay has been dressed into the gutter channel round the frame.

If you are planning a loft room, ask for the roof to be surveyed before the design is fixed. The state of the rafters, battens and covering determines whether the roof can be opened up, and it is better to learn that before the architect's drawings are done.