The short answer
From first call to a fitted skylight, expect a matter of weeks, and sometimes a few months. The fitting itself is a day or two. The calendar is made of other steps: the survey, the written job plan, any permission step, the order lead time for the unit, and Building Control notification. Stock roof windows move fastest. Made-to-measure flat rooflights and lanterns take longest.
Why the fitting day is the short part
People asking for a skylight lead time usually mean the wait before anyone arrives on the roof. That wait is made of several separate steps, most of them done at a desk or in a factory. The fitting day itself is the end of the sequence, not the start.
A rooflight lead time is also the sum of steps that run one after another. The order cannot go in until the size is confirmed, and the size cannot be confirmed until the survey is done. Where a permission step applies, the order waits for that too. Mapping the sequence at the outset is what lets us give you a date you can plan around.
The steps in order
The sequence below is the typical order for a first-time installation. A replacement skips some steps, and a straightforward like-for-like job can move quickly.
Durations are stated as ranges because the real figure depends on the product, the season and the street. The job plan replaces the range with dates once the unit is ordered.
- Free survey at the house, usually within a week or two of the first call
- Written quote and job plan after the survey, normally sent within days
- Permission check for the address, and an application if one is needed
- Order placed once you accept the quote and any permission is in hand
- Wait for the unit to arrive from the maker
- Building Control notified where the work is notifiable, before the fitting starts
- Fitting day, agreed when the unit is ordered
The permission step
Most rooflights on a house are covered by permitted development, so for many jobs there is nothing to wait for. Where there is doubt, the right move is to ask the council in writing. A Lawful Development Certificate is that written confirmation. A householder planning application is needed where permitted development does not apply, for example in a street where a condition or an Article 4 direction has taken the rights away.
Councils publish target decision times for these, and they are measured in weeks. Check the current timescale on the Swindon Borough Council or Wiltshire Council pages, or on the Planning Portal. Our rooflight planning permission guide explains which route applies and what the limits are. Before you commit, we look up what applies to your street and tell you what we find. The decision itself stays with the council.
Stock units against made-to-measure
Roof windows in standard sizes are usually stocked by merchants or can be delivered from the maker in days to a couple of weeks. A standard size is one that matches a catalogue code, which is why the survey records the existing size code or the space between the rafters.
Flat rooflights and roof lanterns are normally made to order. The maker builds the frame and glass to your measurements, so the wait is longer, typically some weeks and sometimes more at busy times of year. A lantern with special glass, a bespoke colour or a large span sits at the long end. Ask the maker for the current lead time when the quote is accepted, because it moves.
| Unit | How it is supplied | Typical wait |
|---|---|---|
| Standard roof window | Catalogue size, often stocked | Days to a couple of weeks |
| Sun tunnel | Catalogue kit | Days to a couple of weeks |
| Flat rooflight | Made to measure | Some weeks |
| Roof lantern | Made to measure | Some weeks, longer for large spans |
| Conservation rooflight | Made to measure | Some weeks |
Building Control and the fitting date
Cutting a fresh opening for a rooflight is building work, and swapping a whole unit is notifiable too. Notification goes to Building Control before work starts, either to the local authority or to a registered building control approver. We handle it where the work is notifiable, and it runs alongside the order wait rather than adding to it.
Once the unit is on order we fix the fitting date with you. At that point the maker gives a delivery window, and we book scaffold or access and the team around it. A one-day fit for a roof window, or a longer one for a lantern, goes down in the job plan, so you know which day to expect us, and by the end of that day the roof is weathertight again.
What can stretch the calendar
Four things move the date most often. A permission application that needs a decision. A made-to-measure unit with a long factory queue. A survey that turns up something above the ceiling, such as wiring or a water tank in the way, which means the plan changes before anything is ordered. And weather, because a roof is not opened in rain.
None of these is a reason to avoid starting. They are the reason the plan is written first. Our answer on lantern fitting time and answer on roof window fitting time cover the fitting days themselves.
Reading your own timetable
Work backwards from the date you want. If you hope to have a lantern in before a family event, count the made-to-measure wait first, then add the survey and quote at the front and any permission step before the order. If the total does not fit, it is better to learn that at the start than in the middle.
A roof window on a house with no permission question is the quickest route. A conservation area, a newer estate with a planning condition or a listed building adds a step that nobody can speed up from outside the council.
Getting a date from us
Ridgeway Skylights gives the survey and the written quote free. The job plan that comes with the quote has a row for lead time and a row for the fitting day, filled in with the real figures for your unit once they are known. Ranges before the order, dates after it, and a ten-year workmanship guarantee when the roof is finished.