The short answer
It depends on the job, and the written quote gives you the programme before work starts. A like-for-like swap in an existing opening is the quickest case. A new opening, a lantern or a deep plastered finish inside takes longer, because each stage has to be done and left to set properly. The roof is made weathertight each day, so the house is never left open to the rain.
How long a rooflight installation takes depends on three things
It is one of the first things people want to know about skylight installation in Coventry. People often ask how long a rooflight installation takes expecting a single answer. The honest one is that the time follows the scope. Three things decide it: whether the opening already exists, how big and heavy the unit is, and how much finishing the room needs once the unit is in. At the free survey we look at all three and put the programme in the fixed written quote, so you know before you commit what the days will look like.
Replacing a unit in an existing opening
This is the simplest case. The old unit comes out, the opening and its surrounding structure are checked, the new unit is fitted and weathered into the covering, and the inside lining is made good. Because the opening has already been framed, there is no structural work to do. A standard roof window swapped for another of the same size is the quickest kind of job we fit. The only variable is the state of the opening once the old unit is out, which we check carefully at the survey so that surprises are rare.
Forming a new opening
A new opening takes longer because it adds structural work. The roof covering is lifted, the rafters or joists are cut and trimmed with new members, the insulation is reinstated and the unit is fitted. On a flat roof, a kerb or upstand may need building and waterproofing before the rooflight sits on it. Each of these stages must be done in order, and some, such as waterproofing layers, need time before the next layer goes on. The sequence is the reason a new opening cannot be hurried without risk to the finished roof.
Lanterns, large units and access
A roof lantern is a bigger piece of kit. It is often made to measure, delivered as a single frame or in sections, and lifted into position. Larger and heavier units need more people and sometimes lifting equipment, and setting up and removing access, such as a scaffold tower, takes time of its own. Where the unit is made to order, the lead time before the fitting date is longer too, because the maker builds it to the dimensions we take at the survey. The date for fitting is agreed once the unit is confirmed, and you hear from us if anything changes. For more on lanterns, see the size guide for roof lanterns.
Inside the room
The finish inside is part of the job, and it has its own timing. Where the roof depth allows, the reveal is splayed so light spreads into the room, then lined and plastered. Plaster needs time to dry before it can be decorated, so we plan for that rather than leave you with a finished roof and a wet reveal. If you have a room freshly decorated, tell us at the survey, so that we protect it and sequence the work to suit.
From survey to fitting
The time on your roof is only part of the story. The sequence runs from the free survey to the written quote, then to confirming the unit and the date, then the fitting itself, then the completion certificate where the work is notifiable. For stock roof windows the gap between agreeing and fitting is short. For made-to-measure rooflights and lanterns it is longer, and we tell you the expected lead time in the quote. Skylight installation time is therefore best thought of as a plan with stages, not a single number. If you are working to a deadline, such as a family event or a builder following on, tell us at the survey and we will say honestly whether the dates can meet it.
How you can help the job run smoothly
- Clear the space under the opening, and move furniture and valuables from the room.
- Tell us about parking and access for ladders, a tower or a delivery of a larger unit.
- Let us know about loft contents or stored items near the opening.
- Say early if the room is freshly decorated or has a floor we should cover.
Weather and the working day
Weather is planned for, not ignored. The roof is made weathertight at the end of each day, with temporary protection over any open part until the unit is fitted and flashed. Wind and heavy rain can still pause the work on the roof itself, for safety, and we move the date rather than rush. When you book, you will have a date, a plan for the stages and a contact who can tell you how it is going.
Where the work is notifiable, the Building Control notification is made by us, and the inspection is fitted around the work. What Building Control involves is covered in this short answer.
