When you call for a window cleaning quote, you'll often hear the term 'per pane.' But what exactly is a pane — and does that mean the same thing for a double-hung window as it does for a French door or a picture window? Understanding pane counting is the key to understanding how your quote is calculated.
The Definition of a Window Pane
A window pane is a single piece of glass within a window frame. It's not the entire window unit — it's each individual piece of glass separated by a frame, sash, or muntin.
For example, a standard double-hung window has two sashes — an upper and a lower. Each sash holds one pane of glass. So a double-hung window = 2 panes. A sliding window with two panels? Also 2 panes.
This matters because professional window cleaners price per pane, not per window or per hour. Each pane has to be cleaned individually — cleaned, squeegeed, and detailed — so the effort scales with the pane count, not the window count.
Pro Tip: Quick rule of thumb: count the individual pieces of glass, not the window frames. That's your pane count.
Common window types and their pane counts
How Common Window Types Break Down Into Panes
Double-hung window: 2 panes (upper sash + lower sash). The most common residential window in the Fox Valley.
Single-hung window: 2 panes. Looks the same as double-hung, but only the lower sash moves. Still counted as 2 panes.
Sliding window: 2 panes (one stationary panel + one sliding panel). Sometimes 3 panes on wider units.
Casement window: 1 pane per casement. A single casement = 1 pane. A double casement (two side-by-side) = 2 panes.
Picture window: 1 pane. Fixed, non-operable, and often large. Still counted as 1 pane regardless of size — though very large picture windows may carry a size surcharge.
Bay window: typically 3–5 panes. The large center picture pane is 1 pane; each flanking casement or double-hung adds more.
Bow window: 4–6 panes depending on the number of panels in the curved configuration.
Awning window: 1 pane per awning unit. Often installed in pairs or stacked, so a 2×2 awning configuration = 4 panes.
What About Divided Lites and Grids?
Many homes — especially in traditional Fox Valley neighborhoods like Geneva's historic district or Batavia's older subdivisions — have windows with grids or divided lites. These decorative bars divide the glass visually into smaller squares.
Here's the key distinction: if the grids are real (true divided lites), meaning each small square is an actual separate piece of glass with its own frame, each small square is a pane. True divided lites are counted individually.
If the grids are simulated divided lites (SDL) — a decorative grid overlay attached to the outside of a single large pane — the entire surface is still one pane. The grid overlay gets cleaned along with the glass.
Most modern windows use SDL grids for aesthetics without the cleaning complexity of true divided lites. When in doubt, your technician will assess on-site.
Pro Tip: Not sure if your grids are true or simulated? Press lightly on a grid bar near the center of the window. If it flexes or feels like a plastic/metal overlay on the glass, it's simulated. If it's rigid and part of the frame, it's likely true divided lites.
True divided lites vs. simulated grids — counting rules
French Doors and Patio Doors
French doors are a common source of confusion. A pair of French doors with 8 glass panes per door = 16 panes for the pair. Each individual rectangle of glass counts as a pane.
Sliding patio doors are simpler: one stationary panel + one sliding panel = 2 panes. If there's a screen, that's typically counted and cleaned separately.
French door sidelights (the narrow windows flanking a front door) are also counted individually — each sidelight panel is one pane.
French doors and divided lite pane counting
Why Per-Pane Pricing Is Fair
Per-pane pricing is transparent and consistent. You can count your panes before calling, understand exactly what you're paying for, and compare quotes on an apples-to-apples basis.
Hourly pricing, by contrast, penalizes you for slower conditions (hard water buildup, construction residue, very dirty glass) and creates uncertainty. Per-pane pricing means the quote is the quote.
At Foxy's, we provide a firm estimate before starting. The pane count determines the base price, with add-ons for hard water treatment, interior cleaning, screen cleaning, and stories above grade.
Pro Tip: Before calling for a quote, do a quick walk around your home and count the glass panes (not window units) on each side. It takes 5 minutes and makes the quote conversation much faster.
Foxy's Window Cleaning · Geneva, IL
Want a firm estimate for your home? We count every pane and give you a clear quote before we start — no surprises.