A single window into a sound concrete tiled slope is generally a day. Slate takes longer because the covering has to be removed and reinstated carefully. Trimming a rafter adds time. And where the work is part of a loft conversion it stops being a job of its own and becomes a stage in a longer programme.
Where the general position is set out
The rule that an opening is never left unweathered overnight, what a winter day allows, and what weather stops work, apply to every rooflight.
They are on how long does a flat roof rooflight take to install.
This page is what a pitched covering adds.
What the day contains
Access, then the covering, then the opening, then the unit, then the covering again.
Tiles or slates lifted and set aside, battens cut, the opening trimmed, the frame fixed, the kit dressed in, and the covering reinstated around it.
The covering is handled twice, which is what makes the covering type the main variable.
Why slate takes longer
Removal and reinstatement are both slower. Slates are drawn with a ripper rather than lifted, they break if handled carelessly, and reinstating so the courses run true either side of the opening takes setting out.
Allow half a day more than the same window in concrete tile.
Why hand made tile takes longer again
Because the gauge varies down the slope.
Soakers are dressed to the courses as they actually lie rather than to a nominal dimension, which is craft rather than kit fitting.
On stone it is longer still, and it is a leadworker’s day.
Trimming a rafter
Adds several hours and occasionally a day.
Cutting a rafter, fitting trimmers to the rafters either side, and fixing them properly is carpentry that has to be right rather than quick.
Between trusses, where nothing is cut, it is considerably faster.
Scaffold time
Not our day, and it affects the calendar.
A scaffold is erected before and struck after, which on a loft slope means two additional visits by somebody else and a period when it is standing.
Where a highway licence is involved, the dates are fixed by that rather than by us.
The lead time on the unit
Frequently the longest part of the process.
Standard sizes are generally available quickly. A made to size unit or an unusual kit is manufactured to order.
Which is why a date follows the order rather than the quote.
Sourcing matching slate
A lead item of its own on a slate roof.
Reclaimed slate of the right size, thickness and origin takes finding, and starting without it is how a roof ends up patched in something that does not match.
The building control visit
A sequencing item rather than a delay.
Where the work is notifiable, the inspector wants to see the trimming before it is closed up, so the job is arranged around that rather than boarded and inspected afterwards.
Making good
Generally a separate visit on a retrofit.
Plastering a splayed reveal wants the opening finished and then time to dry before decorating, so it is a plasterer returning rather than the same day.
It is arranged rather than left to the householder.
Two windows on one slope
A day and a half rather than two.
The access, the set up and the perimeter covering work are shared, so the second opening adds forming, fitting and reinstating.
As part of a loft conversion
Where it stops being a discrete job.
The windows go in when the structure is complete and before the insulation and plasterboard, which is a stage in somebody else’s programme rather than a day of ours.
Coordinating that is on the Barnham page.
During a re-roof
Barely a separate operation. The covering is already off and the battens are being replaced, so forming the opening and dressing the kit in adds hours rather than a day.
What delays a start
Three things, and none is the work itself.
A made to size lead time, a scaffold date, and on a designated or listed building a consent.
All three run in parallel where we are organising them.
What a household experiences
One room, one day, and dust. The room is sheeted, the ceiling opening sealed while it is cut, and the debris carried out. In a loft that generally means one bedroom out of use for a day.
Reinstating the courses
The part of a pitched installation that takes longest and shows most.
Tiles or slates have to go back so the courses run true either side of the opening and the gauge is maintained, which on a hand made covering means setting out rather than replacing what came off.
Done quickly it is visible from the ground for the life of the roof.
Why a second window is not double the time
A question worth asking before deciding on one.
Access, scaffold, protection and setting out are done once whether one unit goes in or two, so a second window in an adjacent bay adds an opening and a set of courses rather than a whole second day.
Two on the same visit is usually the better value and always the better light.
How we scope it
We scope the day around the covering rather than the window, source matching material before starting, and sequence the job around the inspection where one is required.
The whole picture is on the roof window installation page.
Thinking about this job? We survey across Worthing, West Sussex and the South Downs and give you a fixed price before any work starts, with a 10-year workmanship guarantee.