Portchester
Salt air, a Roman fort and a lot of semis: what suits a Portchester roof?
A harbourside village with a castle at one end and long runs of interwar and post-war housing behind, where the weather off the water matters as much as the planning map
Portchester is known for its castle. The Roman walls of the fort, the Norman keep and the church inside the walls stand on the shore of Portsmouth Harbour, and the old village grew along the lane that leads to them. The rest of Portchester is a different place: streets of interwar semis and bungalows, estates from later decades, shops along West Street and houses climbing towards Portsdown Hill. The result is a village with two kinds of roof, one old and tight and one suburban and varied.
Both want daylight, and both offer a chance to get it from above. What differs is how we go about it. Old cottage roofs need a light touch and a check on designations. Newer roofs need care over pitch, structure and the weather. In each case your builder receives the sizes on paper ahead of any work, and ordering happens to suit the build.
Cottages and houses near the castle
Close to the castle and along the old streets are cottages and older houses with clay tile or slate roofs, small in plan and steep in pitch. A bedroom or study under the roof here is often lit by a single small window or none. A conservation rooflight, with its slim frame and low profile, sits down in the covering and keeps the roof looking as it should from the lane. Where a house is outside any designation and the roof is not visible from the street, a standard roof window can also be chosen.
Part of the old village is conservation land, and the castle itself is a scheduled monument looked after by English Heritage. We do not assume what applies to a named house. We look up the address, see whether a designation or a listing covers it, and report. The castle's setting is an obvious reason why a front slope facing it deserves more thought than a rear one, and the local planning authority decides.
The old roofs are often quirky underneath. Rafters may be thin and irregular, and chimney breasts or party walls can sit exactly where a window ought to go. A survey from inside the roof space shows what the timbers will allow, and your builder gets a clear note of which rafters are to be trimmed.
Interwar semis and short terraces
Behind the old core, the interwar semis and short terraces form much of the village. They usually have hipped or gabled tiled roofs, with rafters laid out regularly, and loft conversions are common. The standard pattern is a rear dormer with windows on the front slope, and the front windows need to look as though they belong to the house. We set them in line with the windows below, at a spacing that matches the bays, and choose a size that suits the proportions of the roof.
Where the loft is not being converted, a smaller job still makes a difference. A landing under the roof with no window can feel like a corridor in the dark. A sun tunnel, which takes daylight from a small dome down a reflective tube and out through a diffuser in the ceiling, lights it without altering the structure. It suits halls, landings, cloakrooms and bathrooms that have no outside wall.
Bungalows and the post-war estates
The estates of later decades include a great many bungalows and chalet bungalows with concrete tiles at shallow pitches. A window for a roof of that pitch has to be rated for it, because each maker states a lowest pitch for every model and flashing kit. We measure on site. If a pitch is on the low side, the options narrow and the quote says why, which is better than finding out when the tiles are off.
In a chalet bungalow, adding windows to a bedroom in the roof can transform it. The aim is to light the whole floor and to put the sill at a height that allows a view from a chair or a bed. A window that opens gives a way to move warm air out of a room that sits directly under the tiles, which helps in summer.
Extensions, flat roofs and garages
Plenty of Portchester houses have grown backwards, and plenty of garages have been converted or lengthened. Both lead to flat roofs, and flat roofs lead to rooflights. A kitchen that has been pushed out into the garden often has a dark middle. A flat rooflight or a pair brings light across the floor. For a bigger extension, a roof lantern adds height and a feeling of space, though it needs a taller kerb and more headroom.
On these roofs a carpenter or roofer builds the kerb, working from the sizes we supply. As a rule of thumb the finished upstand reaches 150mm or a little more above the new roof covering, following the maker's instructions. The membrane, felt, EPDM or GRP, goes up the kerb before the glass is lowered into place. If a roof has a plastic dome that has yellowed or cracked, the best time to swap it is when the roof is recovered, because the covering is open already.
A flat roof with a new rooflight should also have the right fall. Water that stands near the kerb is bad for the covering, so the roofer and the carpenter need to agree the falls with the opening in mind.
Views, glare and privacy under a roof window
Houses on the slopes towards Portsdown Hill sometimes have long views south over the rooftops towards the water, and a roof window in the right place can bring some of that into a loft bedroom. A window that faces the view needs thought about glare and privacy together. Fitted with a blind that runs on side tracks, it can be dimmed at midday or blacked out at night. A blackout blind is easiest to order with the window, so we raise it at the survey.
On the street side, windows in the front slope of a semi look straight at the opposite roofs, not at people, and the pitch usually keeps the sill above eye level for passers-by. Even so, in a bathroom we suggest obscured or frosted glazing as a matter of course.
When the old unit has to come out
Some Portchester houses have rooflights from earlier extensions that are now past their best. A cloudy sealed unit, a cracked dome, a frame whose finish has gone dull in the salt: each makes a case for replacement. Taking the old unit out also shows the state of the kerb and the covering around it, which is the point at which any further work is best planned and not discovered later. We say in the quote who is expected to make good around the new unit and when.
If the whole frame and glass is being replaced, the work is notifiable to Building Control, and the notification is ours to arrange. A like-for-like swap of just the glazed panel is treated differently, and we tell you which category your job falls in.
What the harbour air does to a rooflight
Portchester sits on the shore, and salt in the air is part of everyday life here. It affects metal parts and fixings, and it leaves a film on glass. Frames in aluminium with a durable finish and fixings suited to a coastal setting hold up better than basic ones, and we name the finish in the quote. Wind off the water can also be strong, so the way a unit is fixed to its kerb and how an opening unit behaves in a gust are matters for the specification.
A self-cleaning coating helps with dust and rain streaks, though a salt film still needs washing off from time to time. For a rooflight that is hard to reach, it helps to decide how the glass will be cleaned before the unit is chosen.
Planning and building rules in Portchester
Planning for Portchester sits with Fareham Borough Council, whose website is fareham.gov.uk. On an ordinary house a rooflight is often dealt with under permitted development, which our planning guide explains. Those rights do not extend to listed buildings, and a particular property may have lost them to an Article 4 direction or a planning condition. For any named street we check the position instead of presuming it.
Building Regulations apply separately. The Building Regulations guide sets out the thermal limits and what counts as notifiable work.
Ordering around the build
If you have a builder, ask for the likely roof date and give it to us early. We measure, settle the unit with you, pass the sizes over and place the order so that the delivery date matches the stage the roof will have reached. Lantern lead times run longer than stock roof windows, so lanterns go on order first. The quote states the lead time, which comes from the maker.
Fitting follows a set order: the roofer completes the covering, our fitters set the unit, and the plasterer leaves the reveals till last. Where the unit is electric, the cable went in earlier, at the electrician's first fix. At 15.4 road miles out, Portchester allows a return visit if the roof surprises anybody.
Portchester lies 15.4 road miles east of Southampton, beyond Fareham on the M27 at the head of the harbour.
