The short answer
Short answer: a three section splay bay usually lands between £950 and £1,550 fitted, and a four section box bay between £1,250 and £2,100. A bay is not one window with a bigger price, it is three or four windows joined by mitred T posts, and the posts are where the extra money goes.
- Three section splay
- £950 to £1,550 fitted
- Four section box
- £1,250 to £2,100 fitted
- Survey length
- About 45 minutes for a bay
Bays are priced by section, not by window
Quote software treats every pane in the bay as its own shutter, because that is how it is made. Three panes means three frames, three sets of louvres, and two mitred corner posts cut to the exact splay angle. That is why a bay roughly the same total width as two flat windows still costs noticeably more than two flat windows.
The corner posts are the part nobody sees on a price list. Each one is cut on the workshop saw to the angle we measured on your bay, often 22.5, 30 or 45 degrees, and often a degree or two off the drawing because a century of settlement has moved the brickwork.
The four numbers that decide your bay quote
Every bay survey produces the same short list, and those numbers, not the postcode, set the price.
- Total glazed width across all sections, measured at top, middle and bottom
- Drop at each corner, because bay cills are rarely level end to end
- The splay angle at each join, taken with an angle finder rather than assumed
- Reveal depth at the shallowest point, since 65mm is the minimum for full louvre clearance
Where people spend more, and where they should not
Spending more on the frame specification is usually worth it in a bay, because the eye follows the vertical lines across three panels and a thin frame shows every mismatch. Spending more on hardwood is worth it if the bay is over about 2.4m of total width, where panel weight and long term stability start to matter.
Spending more on tier on tier in a bay is a room by room decision rather than a default. On a front bay overlooking a pavement it earns its money. On a rear bay looking at your own garden it often does not.
Getting an accurate bay number
We survey bays free of charge across Warrington and Cheshire, and we do not price a bay from photographs or from your own tape measurements, because the angle is the one thing a homeowner cannot reliably take. The written quote is supplied and fitted, VAT included, by our own fitters.
Common questions
Why is a bay more expensive than two flat windows of the same width?
Because a bay needs mitred corner posts cut to your exact angles, plus a separate frame for every section. The extra labour sits in the corners rather than in the glazed area.
Does a curved bay cost more than a splayed one?
Usually yes, by roughly 10 to 20 per cent, because we approximate the curve with four or five narrower faceted panels rather than three standard ones.
Can I shutter only part of the bay to save money?
You can, and cafe style across the full bay is the most common way to do it. Shuttering one section and leaving the others bare almost never looks right.
Is the bay survey really free?
Yes. The home visit, the angle measurements and the written quote are free with no obligation, wherever you are on our patch.