How Long Does a VELUX Take to Fit?

This is the baseline. The old window is replaced by a new one with the same size code, in an opening that does not change. The rafters keep their places and the new frame drops into the space the old one occupied.

The work runs in a set order. The sash and frame come out, the surrounding covering is lifted, the new frame is fixed and the flashing and collar are fitted. The covering goes back, the sash is hung and the window is run through its full range. The lining inside is finished last.

With nothing structural to wait for, this is a single-visit job; VELUX describes most replacements as done in about four hours. A good deal of that time goes on the flashing, since that is where the roof is made watertight again.

Each of the following adds a stage. None of them is a problem; each is a reason the quote gives a longer figure.

• A bigger window. The opening is enlarged, which can involve rafter trimming and Building Control. Our answer on fitting a bigger VELUX explains the structural side.
• A new opening in a solid roof. The covering is opened, a rafter is cut and trimmers are fitted before the window goes in.
• A group of windows. Windows joined side by side or one above another need a combination flashing and careful setting out, and every opening carries separate labour.
• Electric or solar-powered units. The motor, the controls and the power supply add a stage.
• A different covering from the old one. A re-roofed slope may need a new kit, which is why we read it before we order.

The time is stated against each of these in the quote, so you can see where it comes from. If one of them applies to your roof, it is named at the survey, and the sheet shows what it adds.

The window is not ordered until the survey is done. The survey gives the size code, the flashing kit and the pitch, and from these the order is placed. Waiting time sits between the order and the fitting, while the window is made and delivered.

The expected wait belongs on the quote, and a fitting date makes most sense once the window is in hand, since a maker's lead time can change.

Choosing the flashing kit is part of this stage. Our answer on VELUX flashing kits explains how the roof covering decides it.

Timings vary with the roof, so treat this as the order of events and not a clock. The morning starts with dust sheets and a walk through the route from the door to the room. The sash and frame come out, and the covering around the opening is lifted.

The middle of the visit is the careful part: the new frame is set, levelled and fixed, the underlay collar is sealed and the flashing is dressed course by course. Once the covering is relaid, the sash goes in and the window is run through its range of movement.

The end of the visit is clearing up, a final check that the opening works smoothly, and a hand-over of the catch and any controls. The roof is watertight again before the fitters leave.

A roof is open between the old window coming out and the new one being sealed in, so the work is planned around the forecast, and a wet forecast is a reason to move the date. A matched swap is the least exposed job, as the opening can be covered quickly.

Access can add time. VELUX says most replacements can be completed from inside the room, with the flashing and covering reached through the opening. A large window or a covering out of reach that way brings a ladder, a tower or a scaffold into the plan. Our page on fitting a roof window from inside goes through the split.

After a matched swap, the room needs only its lining finished and a clean. A larger or new opening leaves plasterboard to cut, plaster or tape and fill, and paint, and plaster takes time to dry before decorating.

Blinds fitted at the same visit go in last, once the lining is complete. A blind has to be ordered with the window for it to arrive in time, and a blind from an older window will not fit a different size code.

Your quote lists the making good we do and the parts left ready for a decorator.

Replacing a whole window is notifiable to building control, and a new opening needs approval before work starts. For a new opening the inspection may set the pace, because the trimmed rafters are looked at before they are covered.

Where the job includes an inspection, its date sets part of the timeline. When the job is finished, the window is opened and closed through its range and the handle and any controls are shown to you.

A full account of the fitting is on the VELUX window installation page.