Rooflight and Skylight Installation in Saltdean

What we install in Saltdean

Flat roof rooflights to a marine specification, on two quite different kinds of flat roof.

Original 1930s decks on the modernist stock, where the roof is part of the architecture. And later extension decks on the post-war housing behind, where it is an ordinary flat roof job in a hard position.

The specification is the same on both, because the exposure is. Everything else about them differs.

The modernist houses

Built in the 1930s as part of a planned seaside development, and they were a serious piece of design rather than a style applied to a conventional house.

White render, flat roofs behind low parapets, horizontal emphasis, curved corners on the better examples, and windows arranged in long runs. The flat roof is not a compromise; it is the point.

Which means an alteration to it is an alteration to the architecture, and it is treated as one. A domed unit standing proud of a modernist parapet roof is visible, wrong, and permanent.

What a flush unit does for these houses

The recommendation on any original deck, and it is an aesthetic argument with a practical benefit.

A flush glazed unit sitting low, with a minimal upstand and no visible frame from the ground, keeps the horizontal line of the roof unbroken. From the street, and from the higher houses behind, it does not read at all.

It also presents far less to the wind on a clifftop, which is the practical half. On these roofs the right appearance and the right performance point in the same direction, which is not always the case.

The parapet, and the gutter behind it

The detail that decides where a unit can go on an original roof.

These decks drain to outlets set in or behind a low parapet, frequently through the wall to a hopper. The falls are shallow and the outlets are few, and the whole arrangement depends on nothing obstructing the run of water to them.

A kerb placed across the fall, or close enough to an outlet to catch debris against it, will pond water on a roof that has very little fall to spare. The falls are traced with a level before a position is agreed, not assumed from the drawing.

Ponding on a shallow fall

A recurring finding on these roofs and it is worth checking before anything is fitted.

Ninety years of settlement and successive recoverings have left many of these decks flatter than they were built, and some now hold water in patches after rain.

A rooflight kerb standing in ponded water is a maintenance problem rather than a detail. Where the fall is inadequate we will say so and recommend correcting it first, because a good unit on a ponding deck is work that comes back.

What the covering has become

Rarely what it started as, and it decides the termination detail.

Original asphalt or bitumen, then overlaid or replaced over the decades with felt, single ply, GRP or a liquid system. Some of these roofs carry three generations of covering on top of one another.

Each terminates against an upstand differently, and the detail has to suit what is actually there. It is established by opening up rather than by asking what was done in the eighties.

Insulation, and where it sits

The thermal question on a 1930s deck, and it is a real one.

These roofs were built with no insulation at all. What has been added since is usually above the deck, below it, or occasionally both, and where it sits changes the detail at the kerb entirely.

An uninsulated kerb under a new unit puts a cold bridge directly beneath the frame, and in a room below a flat roof that produces water running down the frame every winter. The detail is on insulating a kerb so the frame does not run.

The Lido, and the designation around it

Saltdean Lido is a nationally significant building of this period, and the interest around it extends to the setting.

Properties within that setting are assessed on how they sit in views of and from it, and the modernist character of the surrounding development is part of what gives the Lido its context.

Which raises the bar on appearance for a rooflight on a nearby original house. It is checked on foot from the places that matter rather than from the front door.

Locally listed and undesignated modernist stock

A category worth understanding, because it sits between the two obvious cases.

A building can be of clear local architectural interest without being nationally listed, and local policy can give that weight in an application. Several of the better modernist houses here are in that position.

It does not stop work. It means the appearance argument carries real weight, and a proposal that respects the horizontal line will be received very differently from one that does not.

Clifftop exposure

The position, and it is among the hardest on this coast.

Wind and salt act on the same components at once. What that combination does, and why it is worse than either alone, is set out on the Rottingdean page, and everything there applies here.

What differs is the roof form. On a flat deck the wind is acting on a horizontal surface and its perimeter rather than on a pitched plane, and that changes where the load goes.

Uplift on a flat roof

The specific mechanism on this stock, and it is worth being clear about.

Wind passing over a flat roof generates suction across the surface, strongest at the perimeter and the corners. On an exposed clifftop deck that suction acts on the covering, the edge details and anything standing on the roof.

Which means the covering’s perimeter fixing matters as much as the rooflight’s. Fitting a well fixed unit into a deck whose edge trims have loosened is solving half the problem, and we will say where the deck itself is the weaker part.

No pitch to shed driven rain

The other consequence of a flat roof in this position.

On a pitched roof, water driven up the slope still has gravity working against it. On a flat deck it does not, and water can be pushed across the surface and held against an upstand for as long as the wind lasts.

So the upstand height matters more here than the standard minimum suggests, and the flashing is dressed and mechanically held rather than trusted to sit. It is the single most common reason a flat roof unit leaks on this cliff.

Render, and what a scaffold ties into

A practical point on the modernist houses specifically.

A rendered elevation hides what is behind it, and on 1930s construction that is not always what you would expect. Ties are placed after establishing what is actually there rather than at a standard spacing.

On a white rendered building any disturbance shows, so ties are made good properly and the render is patched to match rather than filled. It is the kind of detail that decides whether a job looks finished.

The post-war housing behind

A quite different Saltdean up the valley: trussed roofs, concrete tile, and rear extensions with ordinary flat decks.

Here the work is conventional and the position is still hard. Widths between members, the right flashing kit for the profile, and the exposed fixing schedule because the valley is open to the sea at its lower end.

The dimensions are on trussed rafters and the widths that fit between them.

The valley, and how exposure varies along it

A genuinely local point that affects the specification.

The settlement runs inland up a valley from the beach, and the sea reaches up it. Properties at the top, with the valley sides between them and the water, are noticeably more sheltered than those on the clifftop.

So the hardest specification does not apply to the whole village. It is judged at the plot, and we will specify standard coatings where the position genuinely allows them.

Walk-on units, and roof terraces

A frequent enquiry on the modernist houses, because the roofs are flat and the views are extraordinary.

Access onto a roof is a walk-on unit or a hatch rather than a rooflight, with a structural question about what the deck carries and a planning question about overlooking.

On an original 1930s roof it is also an appearance question, because a balustrade above a parapet changes the horizontal line the house was designed around. All three are worth separating from the daylight question early.

Access on the cliff road

Straightforward on the estate and harder on the front.

The valley streets have drives and space beside the house. The clifftop properties are on an exposed road with limited stopping and wind that makes a scaffold a bigger undertaking than its height suggests.

A scaffold on this edge needs more ties and is generally left unsheeted, because sheeting it makes a sail. It is planned rather than improvised and priced as its own line.

What the survey establishes

• Whether the deck is an original 1930s roof or a later extension.
• The falls, traced with a level, and where the outlets are.
• How many coverings are on the deck and how each terminates.
• Where the insulation sits, above the deck or below it.
• The condition of the deck’s perimeter fixing.
• Where the plot sits between the clifftop and the head of the valley.

Building Control

A new opening is notifiable, so we notify Brighton and Hove City Council or an approved inspector and the completion certificate comes back to you. Keep it. It is what a solicitor asks for when the house is sold.

Where the line falls between a new opening and a replacement is on do flat rooflights need Building Control.

Permitted development

On the post-war housing most work is permitted development, subject to the projection limit above the plane of the roof and nothing forward of the principal elevation.

On an original modernist house, and particularly within the setting of the Lido, the appearance question is live whether or not an application is strictly required. Where a proposal would break the horizontal line of one of these roofs we will say so, because the technically permitted answer and the right answer are not the same thing here.

How we quote

A free indicative range by email from photographs, then a survey, then a fixed itemised written price that does not move afterwards. Anything we misjudge at survey is ours to absorb.

What is measured at each step is on the how we price and quote page.

Guarantee

Ten years on our workmanship, on every job, limits written down. The manufacturer stands behind the unit; we stand behind the kerb, the flashing and the making good.

The terms, and the accreditations we do not claim, are on the our guarantee page.