How Long Does It Take to Fit a Skylight?

The fitting itself

The question has a short answer and a longer one. The short answer is that one fitting takes a day or two. On a pitched roof, a roof window can be in and weathered in one day when the roof is clear and the weather is kind. A flat-roof rooflight on a new upstand, or any job that cuts a new opening through the structure, may take two.

The longer answer is that fitting is one stage in a job with a beginning and an end. The days either side matter to your diary as much as the days on the roof.

Before the roof is touched

Everything begins with a free survey. Our surveyor works out the opening, checks the pitch or the upstand position, looks at the structure and talks through the room, the way it faces and the finish you want. Next comes a written quote whose fixed figure holds when we arrive.

Roof windows come in set sizes, so the unit can be ordered at once. A rooflight or lantern for a flat roof is made to your measurements, which takes longer. That lead time sits between the survey and the fitting, and it is the part of the schedule we cannot hurry. We give you the date once the order is placed, so you can plan around it. Ask for the date in writing, and keep it with the quote.

Should the work need notifying, the Building Control paperwork is ours to file, so the paperwork runs alongside the order rather than holding up the roof. Our guide to skylight planning in Milton Keynes explains when permission matters.

How the fitting day runs

The day follows a set order, and the roof is never left open overnight.

1. Access is set up, and the room below is covered and protected.
2. The covering is lifted round the position and the opening is marked and cut.
3. The rafters or joists are trimmed and tied back so the structure carries the load.
4. The frame or upstand goes in, with insulation and a weather barrier round it.
5. The unit is fitted and the flashings are dressed so water runs off onto the roof covering and not into the room.
6. The inside is lined, plastered and finished, then the site is cleared.

If the unit has a deep splay, meaning the angled lining that carries light into the room, the lining and plaster take extra time. The splay is worth the effort, because a wide angled lining spreads light across the ceiling instead of leaving a dark edge. Even so, the finished room should look complete when we leave, not like a job waiting for another trade.

What adds time

Delays come from things we can spot before the day, which is why the survey matters, and why we ask about access, the room and any electrics in advance. Here are the usual causes.

• A made-to-measure rooflight or lantern, which has a longer lead time than a stock roof window and is ordered once you approve the quote.
• A rafter, truss or old timber that needs strengthening before the opening can be cut.
• Plastering and decoration inside, which need drying time before paint.
• Electrics for an opening rooflight or a rain sensor.
• Rain, wind or ice on the day, because no one should open a roof in bad weather.

Weather can move a day, but it does not change the quote. The fixed written quote stands, and we rebook the next dry day.

The whole job in four stages

Put side by side, the stages look like this. Week counts depend on the unit and the roof, so the survey is where they are fixed.

Planning the days around you

Clear the furniture from beneath the opening and tell us where you want the dust sheets. We protect the floor, but a clear room means a faster day. If the unit is going over a kitchen or hall, keep the area free of food and valuables. Pets and children are best kept out of the room for the day, since there are tools, ladders and glass about.

Tell the neighbours too. A polite word before a ladder goes up costs nothing, and a rooflight job is brief enough that most people are glad to hear it will be over fast.

Two further reads help you plan. If you are deciding whether your roof suits an opening at all, see whether a skylight fits any roof. If you are replacing an old unit, the signs it has worn out help you choose the right moment. The main page lists every type of skylight and rooflight we fit.

Every job comes with our 10-year workmanship guarantee in writing, and the rooflight goes in to current Building Regulations, so the speed of the day never costs you quality.

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