When people ask how long new windows take, they usually mean one of two things: how many days the fitters will be in the house, or how many weeks it will be before the job is finished. Those are very different numbers, and mixing them up is the main reason homeowners end up planning a party or a house sale around the wrong date.
Below we split the answer into the time on site, which is short, and the time before it, which is where most of the waiting happens.
Time on site: the short answer
The time on site depends on the number, size and type of units, the condition of the openings and any finishing work. A glass-only replacement generally involves less work than removing an entire frame. Ask for the expected fitting time after the survey.
| Job | Usual time on site | Why |
|---|---|---|
| One misted or failed glass unit | Confirm after survey | Frame left in place, only the sealed unit changes |
| Several glass units | Confirm after survey | Units are made to size before fitting |
| Front or back door | Confirm after survey | The opening and finishing work affect the time |
| Full house of windows | Confirm after survey | The number and type of openings affect the time |
The stages before fitting day
1. The survey
Nothing can be made until the openings are measured properly. We measure every window and door ourselves, and the person measuring is the person who will fit it, so there is no second visit to re-check someone else's figures.
2. The written quote
After the survey you get a clear written quote. That gives you time to consider the work without making a decision during the visit.
3. Manufacture
Windows and doors are made to measure for each opening, so there is a manufacturing period between saying yes and fitting day. Coloured frames, unusual glass and larger sliding or folding doors usually take longer to make than a standard white window. We will tell you the expected timescale for your specific order when you go ahead.
4. Fitting day
On the day, old units come out and are taken away for disposal, the new frames go in, and everything is packed, sealed and finished inside and out. The last job is hoovering up and clearing away.
What a fitting day actually looks like
- Dust sheets down and furniture moved back from the openings being worked on
- Old sash and frame removed one opening at a time
- New frame set level and square, fixed into the wall and packed
- Glass installed and beads fitted
- Gaps filled, external seal run, internal finish tidied
- Handles, locks and opening action checked with you
- Old units loaded up and the room cleaned before moving on
Things that can add time
Most delays are discovered when an old frame comes out, not before. Soft or rotten timber sub-frames, a damaged lintel, crumbling render around the reveal, or an opening that has been badly altered in the past can all need extra work before the new frame can be fixed properly.
Access matters too. Upstairs windows over a conservatory, a steep drop or a busy public pavement can need more care and more time. Weather plays a part as well; sealants and finishing do not like driving rain, and on an exposed site we would rather hold a job than fit it badly.
Will I need to take time off work?
For a single glass unit, usually not for long. For a door or a full set of windows it is best if someone is at home at the start of the day to agree the order of rooms and at the end to check everything works. Our working hours are Monday to Friday, 7.30am to 5.30pm.
Planning around other work
If you are also plastering, decorating or fitting new blinds, put the windows in first. New frames can mark fresh paint and the reveals often need touching up afterwards. If a builder is forming a new opening for patio or bifold doors, the opening needs to be finished and measured before the doors can be ordered.
Common questions
That depends on the number and type of openings and any finishing work. Ask for the expected fitting time after the survey.
No. Openings are done one at a time and closed up before we move on.
We provide a written quote after the survey. Contact us if you need to discuss timing.
Want a straight answer on your own windows or doors?
DM Installations fits and repairs windows and doors across Central Scotland — Cumbernauld, Glasgow, Falkirk, Stirling and the surrounding towns. Free survey, written quote, and an honest answer on whether you need a repair or a replacement.
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