Rooflights and skylights in Steyning, flint to Horsham stone

Steyning stands where the River Adur cuts through the South Downs. The ground, the old port and the hills behind all still explain the way the town is laid out.

The town lies in the Horsham district of West Sussex, about four miles north of Shoreham-by-Sea, and the 2022 census counted 5,832 residents. Wooded Downs slopes rise to the south and east. The floodplain of the Adur lies to the east of the town. Steyning was a medieval port before the river silted up in the 14th century, which is a good reminder that the landscape here has changed its mind before.

For a roof, geography matters in two plain ways. Slopes facing the Downs get shade from trees in some seasons and strong light in others, and a rooflight position is chosen with that in mind. Rain on glass is something we plan for wherever the house stands. Our page on where to position a skylight in a room covers the general rules. What follows applies them to the roofs Steyning actually has.

Many surviving timber-framed buildings in Steyning date from a period of about 100 years, and the High Street includes medieval timber-framed buildings, some with jettied frontages. A roof opening in one of them is planned differently from any other.

An old frame is not a modern truss. The rafters may be irregular in section and in spacing, and they may have been altered over the centuries. Cutting one to make room for a rooflight changes how the roof carries load, so the structural question comes before the glazing question. We look at the frame from inside the loft, decide which members can stay and which need a trimmer or a doubled rafter, and draw the opening to fit the timbers. That sequence is why a survey visit comes before a price.

Planning comes into it as well. These buildings are in or near the conservation area, and some may be listed, so the position is checked for the address before anything is drawn. Our page on conservation rooflight installation explains the style of unit that suits a protected roof, which is a flush-fitting roof window with a slim frame and a low profile against the covering.

On the Bramber Road side of the town the housing is late Victorian and Edwardian. The character assessment describes detached and semi-detached houses in brick and flint, with tile hanging and dormers.

These houses have several roof planes, which makes them easy to light from above and slightly harder to get right. A dormer has a flat or shallow roof of its own. A cheek of tile hanging sits beside it. A steeper main pitch rises behind. Each plane suits a different product. A pitched roof window works on the main slope, and a small flat rooflight or roof lantern can suit a flat dormer top or a rear extension roof.

A few points for houses of this type:

• A flat-roofed dormer or rear extension takes a flat roof rooflight set on an upstand, with a fall on the roof of 1:80 or better so water leaves the glass.
• A larger kitchen or dining extension can take a roof lantern, which brings light from several sides.
• A main-slope loft room takes a roof window set between the rafters, with the flashing dressed to the tile.

A rooflight lets in light, and it can let in noise. In Steyning the sounds worth planning for are simple. They are weather and, where a house faces the bypass, traffic.

Rain is the one every rooflight shares. Flat glass and a lantern roof return the sound of a heavy shower as a drum. The answer is in the build. A laminated acoustic inner pane, panes of unequal thickness, a solid spacer bar and continuous gaskets all change what the room hears. The upstand is part of it too, since a hollow upstand can ring. Our page on reducing rain noise under a flat rooflight explains each part of that build.

Traffic on the bypass is a matter of where the house stands. A bedroom on the side facing the road needs more attention than one at the back. We listen at the survey, at the time of day that matters, and describe what we hear in the written spec. Quiet is described by the specification itself: the glass, the seals and the upstand chosen for that room.

The work itself follows an order, and the order is designed to keep the house weathertight at every stage. Steyning's older roofs ask for a little more patience than a modern one.

The survey comes first. We measure the opening, look at the timbers from inside, check the covering, and listen in the room. The written quiet spec is drawn up from that visit. Then the work starts on a day chosen to suit the forecast. The covering is taken up around the opening, the trimmers go in, the upstand or frame is fixed, the flashing is dressed to the roof covering, and the unit is set. Inside, the lining is finished and made good.

On a clay tile or slate roof the covering is put back in its courses. On a stone roof the slabs go back in their set. The aim at the end is an opening that looks as if it was always part of the roof. Our page about our guarantee covers the 10-year workmanship guarantee, which is not insurance-backed, and what it includes.