When you get a quote for new windows, the double glazing installation cost and the price of the units are usually rolled into one figure. That makes it hard to see what you are actually paying for the fitting. Here we split the two apart so you understand what the installation adds and why the total lands where it does.
The short answer
Most installers, including us, give a single supplied-and-fitted price per window or for the whole job. Behind that number, the fitting labour typically accounts for a meaningful chunk of the total, often somewhere around 150 to 400 pounds per window depending on size, access and the state of the opening. A full-house job spreads the setup time across more windows, so the per-window fitting cost usually comes down.
These are guide figures, not a quote. For a price on your actual windows, request a free quote and we will measure up.
What "installation" actually covers
Fitting is far more than lifting a window into a hole. A proper installation includes:
- Removing the old window and disposing of it responsibly
- Preparing the opening, making sure it is sound, square and ready
- Fitting the new frame dead level and plumb, packed and fixed correctly
- Sealing and weatherproofing inside and out so there are no draughts or leaks
- Making good the plaster, render or trims around the frame
- Adjusting the hinges, handles and locks so everything opens and closes smoothly
- Certification, since the work should be registered under a competent person scheme such as FENSA
That last point matters. Replacement windows come under Building Regulations, and using a registered installer means the work is certified without you having to involve building control separately. Rules change, so check the current requirements, but this is why a cheap "cash job" can cost you later.
What separates the units from the labour
Think of your quote in two halves.
The units
This is the window itself, the frame and glass. Price here is driven by material, style, size, glazing spec and colour. A standard white uPVC casement is the baseline. Our uPVC windows in York page runs through the styles, and casement windows are the most common choice for good reason.
The installation
This is the labour, the removal, the making good and the certification. It is driven by how many windows, how easy they are to reach, and how much work the openings need.
What pushes the installation cost up
Two identical windows can cost different amounts to fit depending on the situation:
- Access: upper-floor windows, bay windows and anything needing scaffolding take longer
- Awkward openings: old lintels, rotten timber sub-frames or crumbling reveals need extra work before the new window goes in
- Structural surprises: a sagging lintel or a bay that is carrying load can turn a simple swap into a bigger job
- Making good: if the old windows were poorly fitted, there may be more plastering and rendering to put right
- Property age: period terraces in York often have thicker walls and non-standard sizes, which adds time
Why doing the whole house is better value
The fixed parts of a job, turning up, setting out, protecting the rooms, clearing up, are spread across every window you have done. Replace one window and you pay for all of that once, for one window. Replace ten and the same setup is shared out, so each window works out cheaper to fit. If your windows are all of a similar age, doing them together usually gives the best value and a consistent finish.
Getting a fair comparison
When you compare quotes, check they include the same things: removal, disposal, making good and certification. A low headline price that leaves you to sort the plastering, or that skips certification, is not really cheaper. Ask each installer to spell out what the fitting covers, and you will be comparing like with like.
FAQs
How much does double glazing installation cost per window?
The fitting labour alone typically adds somewhere around 150 to 400 pounds per window in 2026, depending on size, access and the state of the opening. Doing several at once brings the per-window cost down. Get a quote for your home.
Is installation included in a double glazing quote?
Usually yes. Most installers give a single supplied-and-fitted price covering the window, removal of the old one, fitting, sealing, making good and certification. Always check exactly what a quote includes.
Does new double glazing need to be certified?
Replacement windows come under Building Regulations, and a registered installer certifies the work under a scheme such as FENSA. Rules change, so confirm current requirements, but certification saves you dealing with building control yourself.
Why is fitting cheaper when I do the whole house?
The setup, protection and clear-up costs are shared across every window rather than charged for one. So the more windows you do in a single job, the less the fitting works out per window.
Want to see the full range of styles, colours and glazing options? Download our latest brochure, or request a free quote and we will pop out for a look.