What Happens on Installation Day

The week before

You will have a confirmed date and a programme in days. A few things happen ahead of it.

The unit is delivered, usually a few days before, and it needs somewhere dry and flat to sit: a garage, a hallway, a spare room. Rooflights are awkward rather than heavy and they should be stored upright rather than laid flat.

Where scaffolding is needed it goes up a day or two before, sometimes longer if a pavement licence is involved. Scaffolders are noisy for a couple of hours and then gone.

We will confirm the day before, and we will confirm the weather. A settled forecast matters more than a convenient date, and if the forecast is genuinely poor we will say so and move it rather than open a roof we may not be able to close cleanly. Moving a date for weather costs you nothing and it is the right call every time.

What we need from you

Access to the room below and to the roof space, so somebody needs to be in for the day or to have made arrangements. A parking space near the house if one can be arranged, because everything comes off the van repeatedly. A mains socket. Somewhere to put the old unit and the waste, which we take away.

Clear the room below the opening as far as you reasonably can. We sheet and protect thoroughly, but a roof opening produces fine dust that finds its way past most protection, and moving things out is easier than cleaning them afterwards. Take pictures off the walls in the room; vibration through a ceiling loosens fixings you had forgotten were only just holding.

Shut internal doors and, if you have pets, keep them somewhere else for the day. A cat that gets into a roof space through a new opening is a memorable afternoon for everybody.

Arrival, and the first hour

We arrive between eight and nine and start inside rather than outside.

The floor is covered, the furniture that stays is sheeted, and dust sheeting is hung to contain the working area. Where the ceiling is coming down in a section, that containment is the difference between a dusty room and a dusty house.

Then the roof space is checked once more against the survey: the rafter positions marked, the opening set out, and the position confirmed against what was agreed. This is the last moment at which anything can move, and we will ask you to look at the marked position before anything is cut. It takes two minutes and it has saved more than one customer from discovering that the window they imagined over the desk is actually over the wardrobe.

Opening the roof

The covering comes off first, from outside, over an area larger than the finished opening. Slates or tiles are lifted carefully and stacked, because on an older roof they are going back on and the good ones are not replaceable.

Then the battens and the underlay are cut back, and the roof is genuinely open. This is the point people find alarming and it is the shortest part of the day.

The structural work follows: the rafters cut where the design requires it, trimmers installed above and below the opening, and everything doubled or strengthened as the specification says. On a straightforward job between existing rafters this is an hour or two. Where the structure is being altered to a design, it is longer and there may be an inspection before it is closed up.

Noise peaks here. Cutting timber above a plasterboard ceiling is loud in the room below and audible next door. It is worth telling your neighbours the day before, particularly in a terrace, and worth planning any working-from-home calls around the morning.

The unit goes in

The frame is fitted into the prepared opening, levelled, and fixed to the structure with the manufacturer’s brackets. Level matters more than it sounds: a frame out of true will not close evenly onto its seal for the rest of its life, and it cannot be corrected later without taking it out again.

Then the perimeter, which is the skilled part and takes longer than anything else. The underlay is dressed into the opening. The apron goes on below, lapping over the covering. Side flashings and soakers are worked in course by course. The head flashing goes under the covering above. The tiles or slates are re-laid around it so the coursing comes back true.

By the end of this the roof is watertight. On most single-unit jobs this is reached in the afternoon of the first day.

The rule about the roof being open

We do not leave a roof open overnight. Not covered with a sheet and hoped for, not left because the forecast looks fine.

If a job cannot be completed in the day, the opening is made properly weathertight before anybody leaves, and it is finished the following day. If something is found that stops the work entirely, the same rule applies: the roof is closed first and the conversation happens afterwards.

This is why we will not open a roof in unsettled weather and why a date sometimes moves. It is the least negotiable thing we do.

Inside, and making good

Once the unit is in and weathered, the work moves inside for the reveal.

The opening is lined, insulated tight to the frame on all four sides, and the vapour control layer is sealed to the frame continuously. This part is slow, fiddly and entirely invisible afterwards, and it is what decides whether the reveal stays dry in January.

Then the reveal is boarded and plastered, splayed at head and cill where that has been specified, which is where a rooflight starts to look like part of the house rather than something inserted into it.

Plaster needs to dry before decoration, so if decorating is part of the job it happens a few days later rather than the same afternoon. Whether decoration is included should be settled in the quotation rather than assumed on the day.

Noise, dust and disruption, honestly

The loudest period is the structural work, typically mid-morning of the first day, and it is genuinely loud.

Dust is worst when the ceiling is opened and again when the plaster is sanded. Both are contained as far as containment goes, and neither is invisible. Anybody sensitive to dust should plan to be elsewhere on those two occasions.

Vibration travels further than people expect through a terrace or a semi. Warning the neighbours costs a conversation and buys a lot of goodwill.

The house remains habitable throughout. Water and power are unaffected, the room is usable again by the evening of the roof work, and there is no point at which you need to move out.

Working in an occupied house

Boots come off or covers go on at the door. Radios stay off unless you say otherwise. We clear up at the end of each day rather than at the end of the job, so the room is usable overnight.

Somebody will tell you what is happening at the start of the day and again before leaving, including anything found that you should know about. If the answer to a question is that we need to check, that is what you will be told rather than a guess.

Nobody smokes on site. The waste goes with us.

How long the different jobs take

Programmes vary with access and covering, but the shape is consistent.

Where a job runs over more than one day, the roof is closed at the end of each of them. The figures above are working days on site rather than elapsed days, since plaster drying and decoration sit outside them.

Winter work

People assume rooflight installation is summer work. Most of it is not, and there is no reason it should be.

What winter changes is the amount of daylight and the number of settled days. A shorter working day means a job that takes one day in June might take a day and a half in December, and the programme should say so rather than pretending otherwise.

What winter does not change is the quality of the work, because the roof is only ever open in acceptable conditions. If it is raining, we do not open it. If it is blowing hard enough to make working at height unsafe, we do not go up. The result is that winter jobs are more likely to be moved and no more likely to go wrong.

The one genuine winter constraint is that some sealants and adhesives have minimum application temperatures, and cold slows plaster drying considerably. Both are matters of scheduling rather than of compromise.

If something is found

Occasionally the roof is concealing something: soft timber around an old opening, an unrecorded alteration, wiring in an unexpected place.

What happens then is the same every time. Work stops on that element. The roof is made weathertight. You are shown what has been found, in person and with photographs, and told what putting it right involves and what it costs. Nothing further happens until you have agreed in writing.

You are free at that point to have somebody else do the additional work, or to stop and pay only for what has been done. What will not happen is additional work appearing on a final invoice you never agreed to.

Sign-off, and what you are left with

At the end, the unit is demonstrated: how it opens, how it locks, how it rotates for cleaning if it does, where the ventilation flap and the filter are, and where the drainage channels are that want clearing once a year.

You are given the manufacturer’s documentation, the warranty registered in your name, and our guarantee covering the workmanship for ten years. The Building Regulations notification is submitted where the work is notifiable, and the certificate follows by post. Keep it with the house papers, because a buyer’s solicitor will ask for it years from now.

We would rather you inspected the work before we go than found something afterwards. Look at the reveal, open and close the unit yourself, and say if anything is not right. Almost everything is easier to correct while the van is still outside.