Rooflight Installation in Radley

Working to a term calendar

The defining constraint on any estate of this kind is that the year is divided into weeks when the buildings are full and weeks when they are empty, and the empty weeks are fixed years in advance.

That inverts the usual programme conversation. On a domestic job the question is when the customer is available and what the weather is doing. On an institutional job the question is which vacation the work has to land in, and everything else is arranged around that.

The practical consequences are worth stating. Lead times have to be worked backwards from the vacation rather than forwards from the order, because a made-to-measure unit with a ten-week lead ordered in May will not be on site for a summer start. Contingency has to sit inside the window rather than after it, since there is no option to run a week over. And where a job cannot be completed in one vacation, it has to be designed to reach a safe, weathertight, occupiable state at the end of the window and resume in the next one.

What a summer window actually allows

Summer is the long window and it is not as long as it looks, because it is shared with every other trade on the estate.

Realistically, roofing and rooflight work needs its slot booked against the other work happening in the same building, and access is frequently the contested resource rather than the building itself. A scaffold serving a rooflight installation may also be serving stonework or gutter work, which is efficient when coordinated and obstructive when not.

What works is agreeing the sequence early with whoever is running the estate programme, and being explicit about what we need and when: the days the roof is open, the days the scaffold is required, the days the room below is unusable, and the days making good is happening.

What does not work is arriving in July having assumed the building would be empty and available, and finding a summer school in it.

Occupied buildings, and the rules that follow

Some estate work has to happen in term, and where it does the constraints are considerable and entirely reasonable.

Noise is the first. Cutting timber above a ceiling is loud, and it is incompatible with teaching in the rooms below and often beside. That usually means the noisy phases are scheduled outside teaching hours or into a half term, with quieter work in between.

Segregation is the second. Working areas have to be genuinely separated from occupied areas, with the route to and from the work not passing through spaces in use. Scaffolding on a site with young people on it needs its ladders removed or secured out of hours as a matter of course.

Safeguarding is the third, and it is not negotiable. Anybody working on a school site during term is subject to the institution’s own requirements on checks, identification, signing in and supervision. That is a condition of the work rather than an inconvenience, and it needs establishing at the quotation stage rather than at the gate on the first morning.

Buildings of every date on one site

An estate of this age is not one construction type. It is a Victorian core, inter-war additions, post-war blocks, and recent buildings, each with a different roof.

The older ranges carry slate or plain tile on hand-cut structures, sometimes with substantial spans and purlins, often with no underlay. These take hand-formed lead perimeters and the openings go where the structure permits.

The mid-century buildings frequently have flat roofs, and a flat roof of that age is where the interesting questions are: whether the build-up is warm or cold, whether the existing kerbs are anywhere near an adequate height, and whether the deck is sound enough to build off. A great many kerbs from that era are 75mm or less, which is well under the working minimum of 150mm from the finished surface, and fitting a new unit onto a short kerb reproduces the fault that failed the old one.

The recent buildings are conventional and straightforward, and the main consideration there is not damaging a warranty, which is covered below.

Institutional flat roofs and non-fragility

One requirement applies on an institutional roof that rarely arises domestically, and it is worth understanding.

Where a roof is accessed for maintenance, any glazing somebody could fall onto or through has to be non-fragile, assessed to the relevant standard rather than assumed. A domestic flat-roof unit specified for a garden room is not automatically suitable for a roof that a maintenance team walks across.

This is a specification decision at order. It affects the glass make-up, sometimes the frame, and it costs more. It is also the sort of thing that gets missed when a domestic product is specified for an institutional setting because it looked equivalent in a catalogue.

Where glazing is genuinely in a walked route, the answer may be a walk-on unit rated for foot traffic, which is a different product again. Establishing which of the three situations applies is part of the survey.

Ventilation and overheating in teaching spaces

Rooms full of people generate heat and moisture at rates a domestic room does not, and roof glazing interacts with both.

On the heat side, a room with a west-facing rooflight and thirty occupants on a June afternoon is a genuine overheating problem rather than a comfort preference. Solar control glazing with a low g-value is the baseline on any sun-facing slope, and opening units at high level give a stack effect that removes heat without any energy input.

On the moisture side, occupancy raises humidity considerably, so the reveal detailing and the vapour control continuity matter more, not less. A cold bridge at the perimeter that would show occasionally in a domestic bedroom will show routinely in a full classroom.

Where units are electrically operated, the controls matter. A vent nobody can reach and nobody knows how to operate is a vent that stays shut, and a rain sensor is worth having on anything that might be left open when a building empties.

The village stock

Away from the estate, Radley is a small village with mixed housing: some older stone and brick cottages, some twentieth-century development, and the usual scattering of converted outbuildings.

The later houses are ordinary work. Concrete interlocking tile over prefabricated trusses with felt beneath the battens, a profile-specific flashing kit, an opening between rafters, a day on site. Truss diagonals are structural and cannot be cut without a designed alteration, which is the only real constraint.

The older cottages take the usual care: hand-cut structures with irregular spacing, hand-formed lead at the perimeter, and openings placed where the timbers allow rather than where the room would prefer.

The authority for both is Vale of White Horse District Council. There is a conservation area covering part of the village, and listed buildings within it, where consent is engaged for a rooflight anywhere on the building including a rear slope out of sight.

New-build houses and their warranties

Where a house is recent enough to still carry a structural warranty, cutting into the roof is worth a phone call before it is worth a quotation.

Most warranty providers do not prohibit alterations, and most require that work affecting the structure or the weathertightness is carried out competently and, in some cases, notified. What causes trouble is not the rooflight; it is a later claim being declined because an unnotified alteration sits in the area of the defect.

Checking takes one call to the provider and the answer is usually straightforward. It is a great deal easier than establishing the position afterwards.

Paperwork an institution needs and a householder does not

Estate work carries an administrative layer that domestic work does not, and having it ready is a large part of being straightforward to employ.

A written risk assessment and method statement for the specific job rather than a generic one, naming the access method, the sequence, the exclusion zones and the arrangements for working above occupied space. Evidence of insurance at the level the institution requires, which is often higher than a domestic contract needs. Confirmation of the checks and identification arrangements for anybody on site during term. Site inductions attended rather than assumed.

Where the work is notifiable under Building Regulations, the notification and the resulting certificate go into the estate’s own building records, which are kept far longer and consulted far more often than a householder’s. Providing them promptly and in a usable form is part of the job.

None of this is unusual. It is worth listing because a firm that treats it as an afterthought creates work for whoever is managing the estate, and a firm that has it ready does not.

Access on a large site

The buildings on an estate of this kind are frequently harder to reach than a house, and for different reasons.

Courtyards and quadrangles have restricted vehicle access, sometimes through an arch with a height limit, and material has to be carried the last part of the way. Mature trees, which these sites have in quantity, impose exclusion distances and sometimes have protection orders on them, so a scaffold cannot simply be founded wherever is convenient.

Ground surfaces matter too. Scaffold legs concentrate load, and founding them on a lawn, a playing surface or historic paving without spreading that load is how a site ends up with damage that costs more to make good than the rooflight cost to fit.

All of this is resolvable and none of it is quick to resolve on the morning. It belongs in the survey and on the quotation.

What we take on, village and estate

New rooflights and replacements of failed units, domestically and on institutional buildings, including flat-roof units on kerbs built or rebuilt to a proper height. Non-fragile and walk-on specifications where the setting requires them. Programmes written around a term calendar where that is the constraint.

What we do not do is remedial roofing or re-covering. On an ageing flat roof where the covering itself is at the end of its life, the honest answer is that the roof needs a roofer before it needs us, and putting a new unit into a failing deck is money spent twice.

What we need at the enquiry

For domestic work: where in the village, what the roof is covered with, which room, and whether the building is listed or in the conservation area.

For estate work: which building, what the roof construction is if known, whether the area is walked for maintenance, and above all which vacation window the work has to fall in. That last one shapes everything else, and the earlier it is known the more likely the programme is to hold.