Rooflight and Skylight Installation in Southwater

What we install in Southwater

Flat roof extension rooflights on the older phases, and roof windows into rooms that were built in the roof from new.

What we are almost never doing here is conservation work, because there is nothing designated to conserve. The village has no historic core in the way its neighbours do, and that is not a deficiency; it simply means the questions here are technical rather than aesthetic.

A village with no historic core

Worth stating plainly, because it changes the whole shape of a job.

There is no conservation area, very little listing, and no street scene that an officer is protecting. Which means the planning question, which dominates work in Steyning or Henfield, is generally settled in a sentence here.

What replaces it is a set of questions nobody asks about an old building: what the roof is engineered to do, what the dwelling’s ventilation strategy assumes, and what conditions were attached when the estate was approved.

Fink trusses, and the loft you cannot use

The commonest roof on the earlier phases, and it disappoints people regularly.

A standard fink truss is a triangle with a W of webs inside it. It is efficient, it is cheap, and the webs occupy exactly the space a room would need. They are structural and they are not cut.

So a rooflight fits between trusses without difficulty, and a room in the roof does not happen at all without replacing what the webs do, which is a structural design and a considerably larger job than the enquiry started as.

Attic trusses

The other kind, and where the newer housing here has them it changes everything.

An attic truss is designed with a clear rectangular space in the middle, carried by heavier members at the sides, and a bottom chord sized to take a floor rather than only a ceiling. It is a room waiting to be finished.

Where a house was built with them, adding roof windows is straightforward and the positions were frequently anticipated in the design. Where it was not, no amount of wanting one produces the space.

Which one is up there takes five minutes to establish at the loft hatch, and it is the first thing we look at.

Engineered joists in a flat roof

The other engineered component, and it appears in the newer extensions.

Metal web and I-joists are designed members with a specified span and a specified way of being cut, which is generally not at all. Notching one, or trimming an opening without a designed detail, removes capacity the design assumed.

So an opening in a modern flat roof is a designed trimming rather than a carpentry decision. It is entirely routine when done properly and it is not something to improvise.

The air barrier

The item that most often gets damaged and least often gets mentioned.

A modern dwelling is built with a continuous air barrier, and its continuity is what makes the house perform as designed. Cutting an opening through a ceiling and a roof cuts through it.

Continuing the barrier around a new rooflight frame, and sealing it properly to the unit, is part of the installation rather than an extra. Where it is not done, the result is a draught, a cold line and, in time, moisture in the roof build up.

Why an old detail will not do

Worth spelling out, because the temptation is to fit a modern unit the way an older one went in.

In a ventilated Victorian roof, a small amount of air moving past a frame is absorbed by a roof space that is effectively outdoors. In a modern warm roof it is not; the air carries moisture into an insulated build up that has no way of drying.

Which is why the sealing detail matters more on a new house than on an old one, and why we do it as a matter of course rather than on request.

The dwelling’s ventilation strategy

The question nobody expects to be asked about a rooflight.

A modern house has a designed ventilation strategy: background ventilators sized for each room, continuous extract, or a mechanical system with heat recovery. It was calculated for the dwelling as built.

Adding an opening rooflight, or replacing a unit that carried a background ventilator with one that does not, alters what the room actually has. On a house with mechanical ventilation, opening a rooflight in a room the system serves changes how that system behaves.

None of it prevents the work. All of it is worth establishing so the outcome is deliberate.

Airtightness, and whether it matters afterwards

A question people ask and the answer is reassuring.

A dwelling is tested at completion, and the certificate reflects the house as it was then. Later alterations do not invalidate it, and they do change the building’s actual performance.

Which is an argument for doing the sealing properly rather than for not doing the work. A well detailed rooflight costs the house very little; a badly detailed one costs it noticeably.

Solar panels on the slope

A genuinely common obstacle here and it is frequently the thing that decides the position.

A substantial share of the newer housing has panels on the south facing slope, which is also the slope somebody wants a rooflight in. Panels occupy area, they have their own fixings into the structure, and they have cabling running under the covering.

Working around them means knowing where the fixings and the cable runs actually are, which means the installer’s layout rather than guesswork. Removing and refitting panels is possible and it is a separate trade and a separate cost.

Panels and the position that is left

The practical consequence, and it is worth raising early.

Once panels occupy the best part of the south slope, the available positions are at the edges, above or below the array, or on a different slope entirely. Each of those changes what the room gets.

Where the only workable position is a north slope, we will say what that means for daylight rather than fitting it and letting the household find out.

Planning conditions on a new estate

The item most owners are unaware of, and it catches people out.

Permitted development rights are frequently removed by condition when a large estate is approved, so alterations that would be permitted on an older house need an application here.

It is recorded on the original consent rather than anywhere obvious, and it is checked as a matter of course. Discovering it after the work is the expensive way.

Covenants and management companies

A separate matter from planning, and it applies to a good deal of the newer housing.

Estate covenants and management company rules can restrict alterations to elevations and roofs independently of what the council would allow. They are a private law matter and they are enforceable.

Where a property is subject to one, consent under it is obtained alongside anything else. It is worth reading rather than assuming, because the restrictions vary considerably.

Structural warranties

Worth establishing on a house still within its warranty period.

Alterations can affect what remains covered, and the terms differ between providers. It rarely prevents anything and it occasionally changes who needs to be told.

It costs nothing to check at the outset and it removes a question that would otherwise surface during a claim.

Modern coverings and flashing

The straightforward part, and it still has to be right.

Deep profile concrete interlocking tile across almost all of the housing here, which leaves a void under each roll that a flat skirt cannot follow.

Which kit suits which profile is on flashing kits and roof coverings across Sussex. On a modern roof the correct kit is available and there is no excuse for using another.

Insulation depth on a new roof

A dimension worth knowing before a unit is ordered.

Modern roofs carry considerably more insulation than older ones, and in a room in the roof it sits between and over the rafters. The build up is thicker, so the reveal around a window is deeper.

A deeper reveal takes more light out of a room than a shallow one unless it is splayed, and splaying it is a plastering decision made at installation rather than afterwards.

The older phases

Southwater is not all new, and the earlier housing behaves differently.

Seventies and eighties development with fink trusses, deep profile tile, and rear extensions with flat decks built by general builders. There the kerb is the question, and it is measured rather than assumed.

What a builder’s kerb usually turns out to be is on what is a builders kerb.

Access on a new estate

Easier than a village street and not as easy as it looks.

Roads are narrow by design, parking is at a premium, and there is frequently no verge to stand anything on. A scaffold lorry on an estate road at school time is a genuine problem.

Most jobs here need only a tower, which stands within the boundary. Where a scaffold is needed, the timing matters more than the licence.

New gardens, and what a tower stands on

A small point that customers appreciate being asked about.

Newly laid turf and recently made up ground do not take a tower or a barrow without marking, and on a young garden that damage takes a season to recover.

Boards and a bit of planning deal with it. It is worth raising beforehand rather than apologising afterwards.

Inland and sheltered

The environmental position, and it is comfortable.

Well inland, so the salt question does not arise and standard architectural coatings hold up over a normal service life. Wind loading is ordinary.

We will specify standard where standard is right rather than adding a marine grade the position does not need, and we will say so.

What the survey establishes

• Whether the trusses are fink or attic, established at the hatch.
• Whether any flat roof uses engineered joists, and what the trimming detail must be.
• Where the air barrier runs, and how it will be continued at the frame.
• What the dwelling’s ventilation strategy is.
• Where solar panels, their fixings and their cable runs sit.
• Whether a planning condition or a covenant restricts alterations.

Building Control

A new opening is notifiable, so we notify Horsham District 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

There is no designation here, so the ordinary rules apply, subject to the projection limit above the plane of the roof and nothing forward of the principal elevation.

The exception is the one that matters most in this village: where a condition on the original estate consent removed those rights, an application is required regardless. It is checked before anything is specified rather than assumed from the absence of a conservation area.

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.