Bay Windows
Wallpaper for a Bay Window: Measuring a Curved or Angled Bay
A bay window breaks what would otherwise be one flat wall into several angled panes — sometimes three, sometimes five, occasionally a continuous curve on an older bow window. A standard "width × height" calculator wants a single flat wall to work from, and a bay simply doesn't offer one. Here's what actually changes when a wall isn't flat, and how to still measure a bay properly instead of flattening it into a number that doesn't match what's on the wall.
Open the Wallpaper PlannerMeasure each pane as its own short wall
Every flat pane of a bay — the two or four angled sides plus the central face — gets its own width and height measurement, the same as any other wall in the room. The angle between panes doesn't matter for wallpaper purposes: strips hang straight down regardless of how the wall next to them is angled, so there's nothing special to calculate about the angle itself, only about treating each pane separately rather than trying to sum them into one flat total.
The window recess splits panes into sections above and below the sill
Most bay windows have a sill or sub-sill running across some or all of the panes, with a shorter run of wall below it and a taller run above and beside the glass. Measure the wall above the sill and any wall below it as separate short sections on each pane, rather than treating the whole pane height as one continuous strip run interrupted by glass.
A curved bow window needs narrower, more frequent strips
Older bow windows are often genuinely curved rather than angled in flat panes, and a flat strip of wallpaper can only hug a curve if it's narrow enough that the small flat facet it creates isn't visible. That means more, narrower strips and more seams than the same width of flat wall would need — plan for a higher strip count on a curved bay, not the same count as an equivalent flat run.
Corners inside a bay are tighter than a standard room corner
The internal angles where a bay's panes meet are usually less than the 90° corners the rest of the room has, which makes pattern matching across them noticeably harder — a strip that lines up cleanly on a square corner can visibly step out of alignment on a bay's shallower angle. If the pattern needs to read as continuous around the bay, plan which strip starts at which corner deliberately rather than papering pane by pane and hoping it lines up.
Order a buffer roll for the extra seams
Splitting one wall's worth of width into several short panes means more seams and more offcut per metre than the same width papered as a single flat wall would produce. A bay window is exactly the kind of job where the seam count, not the total area, is what drives the waste up — order a buffer roll the same way you would for any wall with an unusually high number of short strips.
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See plans & pricingCommon questions
Is a bay window wall measured differently from the flat walls around it?
Each pane of the bay is measured as its own short wall, the same approach as an alcove's return walls or a hallway's individual straight runs — you're not measuring the bay as one number, you're measuring several small ones.
Do curved bay windows need a different type of wallpaper?
Not necessarily a different product, but a thinner, more flexible paper generally hugs a curve better than a stiff vinyl, which can crack or lift at the tightest part of the curve — check your supplier's guidance for curved or bowed walls before ordering.
Can the planner handle a bay window directly?
There's no single named bay-window template, but the room editor's free-form point-by-point outline handles any number of angled or curved panes — draw each pane as its own short wall the same way you'd sketch it on a floor plan.
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