One figure, printed twice, and this time it says so
| Source | Range | Average | Updated |
|---|---|---|---|
| Fixr | $1,500 to $5,000 | $3,000 | January 31, 2025 |
| This Old House | $1,500 to $5,000 | $3,000 | June 23, 2026 |
Identical range, identical average, seventeen months apart. We have documented this pattern several times across this site, most fully on our window glass page and across our water treatment section, and usually we have to work out where the number came from.
Not here. This Old House states it, in a line at the foot of the article:
Article cost data sourced from Fixr.
Our note, marked as ours, and it is a point in that publisher's favour. Saying so is better practice than most of what we read. It also means you should treat the agreement above as what it is: one dataset, quoted twice, with no corroboration added by the second printing.
The figure the same page measured itself
This Old House also carries a number of its own, and it is not the one at the top:
According to This Old House's 2024 window survey, garden windows averaged $1,537 per unit, making them one of the more expensive window styles. Only specialty/custom shapes, egress windows, awning windows, basement hoppers, and transom windows typically cost more.
Our reading, marked as ours, and it needs care rather than excitement. $1,537 and $3,000 are not two answers to one question. The survey figure is per unit, the borrowed average is installed. So the honest conclusion is not that one is wrong, but something more useful:
Our arithmetic: $1,537 against an installed average of $3,000 leaves $1,463 for everything that is not the window, which makes the unit about 51% of the total.
That is a cleaner split than most window jobs, and it makes sense once you know what a garden window is.
Why installation is half the bill
This Old House describes the thing itself: a garden window is a box that protrudes from your home's exterior wall, similar to a bay window but smaller, with glass on the front, sides and top.
Our reading, marked as ours. That is the same geometry that makes bay windows expensive to fit, which our bay window page works through in detail: anything that projects out of a wall has to be supported, flashed and weatherproofed on five surfaces instead of one. A garden window is a small version of that problem, which is why half the money is the fitting rather than the glass.
It is also why we would not treat it as a like-for-like swap for the window it replaces. The opening may be the same, but what sits in it is no longer flush with the wall.
What size and material do
This Old House prices by size, installation included:
| Size | Installed cost |
|---|---|
| 24 by 24 inches | $800 to $1,700 |
| 60 by 72 inches | $2,500 to $6,000 |
And by frame, for a 36 by 48 inch window: vinyl $1,000 to $2,400 installed, fiberglass $1,100 to $3,200.
It ranks the materials plainly: aluminium is the least expensive but a poor insulator, usable only in mild climates, while fiberglass and vinyl are the most common because they are low maintenance and durable.
Our observation, marked as ours. Note that the size table alone spans from $800 to $6,000, which is wider at both ends than the headline range of $1,500 to $5,000 that both publishers print. The headline describes the middle of the market; your window is a specific size, and the size table is the better guide once you know which one you are buying.
Where it sits among window styles
This Old House's own survey ranking is worth repeating because it is rarely published: garden windows are among the more expensive styles, with only specialty and custom shapes, egress windows, awning windows, basement hoppers and transom windows typically costing more.
Our reading. So a garden window is a deliberate upgrade, not a default. Against the figures on our window replacement page, it is several times a standard replacement, and the comparison that matters is not against other garden windows but against simply fitting an ordinary window and putting a shelf in front of it.
What to take from this
- The two published figures are one figure. This Old House says so at the foot of its article.
- $1,537 is the unit, $3,000 is the job. Do not read them as competing averages.
- About half the bill is fitting, because the box projects from the wall and has to be weatherproofed on every face.
- Use the size table, not the headline range, once you know the dimensions you need.
- It is one of the dearer styles on This Old House's own survey ranking, so price it against an ordinary window plus a shelf before committing.
Sources
- This Old House, How Much Does a Garden Window Cost? (2026 Guide), updated June 23, 2026 (the $1,500 to $5,000 range and $3,000 average, the statement that article cost data is sourced from Fixr, the $1,537 per unit figure from its own 2024 window survey and where garden windows rank among styles, the cost by size and frame material, and the description of what a garden window is)
- Fixr, Garden Window Cost, updated January 31, 2025 (the $1,500 to $5,000 range and $3,000 national average, and the factors it names as driving the price)
Price figures are national US ranges from the sources above as of the date shown. Your local price depends on labor rates, permits and site conditions. Read how we get our numbers.