Salisbury
A city of listed fronts and plain terraces: which kind of roof is yours?
Timber, brick and tile in the old centre, Victorian streets either side of the railway, and newer houses on the edges
Salisbury is a city, and its roofs do not behave like a town's. Across the city you can pass a medieval timber-framed building, a Georgian brick front, a Victorian terrace in slate and a twentieth-century semi in machine-made tile. What looks right on one of those can look wrong or work badly on the next, so a job here starts with a conversation about the building, not a product. The questions are the same everywhere we work: what is the roof covering, who is building or re-roofing it, and when will the roof be ready to receive glass.
In a city with this much protected building, the work may well be planned by someone other than the homeowner: an architect, a building designer or a conservation consultant. When that happens we take the drawing from them and return the exact opening and kerb sizes for the unit chosen, so the drawing and the glass agree before anything is ordered.
Inside the Close and the old chequers
The oldest part of Salisbury is laid out in a grid of blocks known as chequers, and around the cathedral sits the Close, a walled precinct of houses under close protection. Many buildings in and around this core are listed, and the area falls within the city's conservation areas. Roofs here are clay tile or natural slate, steep, with chimneys close to any opening you might want to make.
In this setting the likely answer is a conservation rooflight, a slim-framed unit that lies close to the tiles and carries a single central bar, in black or dark grey, so that from the street it reads like the roof lights older buildings once had. It is a different product from a standard roof window, and the page on conservation rooflights against roof windows sets out the differences in frame depth and glazing.
A listed building needs separate consent for alterations that affect its character, and a rooflight can do so. The process is run by the council and informed by national guidance, which Historic England publishes. Our part is practical: we measure the roof, supply the dimensions and a section drawing of the unit for the application, and tell your builder or conservation architect how the opening is to be framed. The listed building consent page explains what the application usually needs.
Terraces at Fisherton and Bemerton
West of the centre, across the railway line and out along the roads towards Bemerton, the housing is mainly Victorian and Edwardian brick terraces and semis under slate or small clay tile. Here the loft is a likely project: a bedroom and a shower room in the roof, lit from two roof windows set in the back slope. Some of the terraces have a rear outrigger, a lower wing at the back, whose own roof is often flat or shallow and suits a flat rooflight over a kitchen or a bathroom.
Slate roofs need a flashing kit to suit the covering and a roofer who is comfortable lifting slates without cracking the ones next to them. We name the kit in the quote, tell the roofer how many courses to take off and ask for the new battens to be fixed at the heights the frame needs. If the existing window is an old unit that has failed, replacing an old roof window is a smaller job than a new opening, because the rafters are already trimmed.
On a two-storey terrace, a loft room is a third storey. The 4.5m ground-height limit on escape windows rules a roof window out as the way out of that room, and a protected stair from the new room down to the front door is needed instead. This is a point for your designer and building control, and we raise it at survey so it does not catch the project at the inspection stage. The roof window escape page goes through it.
Harnham, Laverstock and the edges
South of the Avon in Harnham, and to the east and north-east in Laverstock and the newer areas around Bishopdown, the roofs change again. There are inter-war and post-war semis and detached houses in concrete tile, bungalows with hipped roofs, and larger gardens that have been given kitchen extensions with flat or low-pitched roofs. This is where a roof lantern or a large flat rooflight fits best: over a dining area extended into the garden, bringing daylight into the middle of a deep plan.
Picking a lantern over a flat rooflight, or the reverse, is mostly about the ceiling height inside and how the roof is built. The lantern or flat rooflight comparison covers it, and lantern sizes explains the dimensions we work with. In every case the kerb belongs to the roofer, and we supply its size.
Flat roofs behind period fronts
Some Salisbury houses keep an unchanged street front and have been extended at the back. The rear roof is flat, covered in single-ply, felt or GRP, and hidden from the street, which usually makes it the easiest place to put a rooflight. It is also where the timing matters most. The membrane has to go up the kerb before the glass arrives, the electrician has to run a cable for any rooflight that opens at first fix, and the plasterer needs the unit in before the reveals can be finished. Who builds the kerb sets out how those jobs are divided.
If the flat roof is already finished, a rooflight can still go in, but it means cutting into a roof that is complete and making good the covering around it. Adding a rooflight after the roof is done describes the process. Where you have a choice, the simpler route is to settle the rooflight before the roofer starts.
Glass and heat loss on a city roof
Whatever the street looks like, the thermal rules for an existing house are the same. Part L sets the heat-loss ceiling for new glazing in an existing house: a roof window has to reach the standard window figure (1.4 W/m²K, or a Band B energy rating), while flat rooflights and lanterns are allowed 2.2 W/m²K. The glazing named in our quote is chosen to meet the figure for the type of unit, so your building control body is looking at a product that already complies, not one that has to be argued for.
In older houses the loft is often where the heat goes, and a new opening is a chance to renew the insulation around it at the same time. The roofer or insulation fitter can work to the splay of the new reveal, and the plasterer closes it after. Doing this as one piece of work saves a second visit and leaves no cold gap between the frame and the plasterboard.
Reading the planning position in a cathedral city
Salisbury's planning authority is Wiltshire Council. Rooflights on ordinary houses can often fall within permitted development, and the rooflight planning guide holds the full conditions. In a place with this many conservation areas and listed buildings, though, the national rules are only the first check. Listed buildings sit outside permitted development altogether, and on an ordinary house a condition attached to an old permission, or an Article 4 direction covering the street, can remove it. We do not guess at either. The address is checked against the council's records and we report back, while the decision itself belongs to the council. If a street turns out to be covered, we would rather learn that before ordering than after. The council's planning pages are at wiltshire.gov.uk.
Fitting it round a Salisbury programme
On a project with an architect and a main contractor, the rooflight is usually one line on a long schedule, and the risk is that it gets ordered late. Our approach is to work back from the date your roofer expects to finish the deck or the slope, place the order against that date, and send you and your builder the confirmed delivery once the maker has acknowledged it. Once the unit is chosen, the delivery time the manufacturer gives is written into the quote.
Our drive to the city is 23.3 road miles, one of our longer runs, so we try to combine a survey with other calls in the area. Tell us when your builder will next be on site and we will aim to coincide, and bring any earlier drawings, listed-building paperwork or photographs of the roof, since each saves a second trip. The survey is free, and the quote that follows names the glass, the lead time and the points we need settled on your side. Salisbury jobs are booked as a single trip where we can, so one visit covers the roof, the space underneath it and where a delivery van can stop.
From Southampton, Salisbury is a 23.3 road mile drive to the north-west, by way of the A36 and on into Wiltshire
