QR codes for car washes

Unattended means the code is the staff

At a self-service or automatic wash there is nobody to ask, so the codes carry the whole customer interaction:

Code	Where	Why
Payment or top-up	Bay entrance sign, at window height	The machine takes the money; the code handles app payment and top-up
Membership / unlimited plan	Same sign, and exit signage	The buyer is someone mid-wash discovering they will come back
Feedback and damage claims	Exit lane sign	A claim route that exists beats a one-star review that mentions it
Offer	Street-facing sign	Off-peak discounts changed without reprinting the sign

The geometry of scanning from a driver's seat

The defining constraint is that the customer is seated in a car:

• Mounting height 1.0–1.3 m — level with a lowered driver's window on everything from a hatchback to an SUV. Signs at pedestrian eye height (1.6 m+) force drivers to lean out or get out.
• Scan distance 0.5–1 m from window to sign → 5–10 cm code by the distance rule.
• Angle the sign a few degrees toward the driver's position rather than square to the lane, reducing skew at the camera.
• Never expect a scan through a closed windscreen — tint, rake and reflections defeat it. The design assumption is an open side window.

Materials: a wash bay is a torture test

High-pressure spray, detergent, wax mist and sun. Paper and standard vinyl fail in weeks. Use weatherproof laminated stickers on aluminium composite board, matt-laminated — a wet gloss panel under floodlighting is pure glare. The outdoor durability guide covers UV fade; budget to replace bay signage yearly rather than discovering the fade when scans stop.

What goes wrong

• Codes mounted at walking-eye height, unreachable from a car seat.
• Gloss signs that scan fine dry and mirror the floodlights the moment they are wet.
• A damage-claim code that opens a generic contact page — claims need a form that captures bay number, time and photos, or the one-star review does it instead.

FAQ

What height should a QR code be for drivers?

Between 1.0 and 1.3 m from the ground — window height for most cars — angled slightly toward the driver. Size it 5–10 cm for the 0.5–1 m gap between a side window and the sign, and assume the window is open, not closed.

What material survives QR signage in a car wash?

Matt-laminated print on aluminium composite. Paper and unlaminated vinyl fail within weeks under pressure spray and detergent, and gloss finishes glare when wet. Expect UV to erode contrast; plan yearly replacement of bay signs.

Do car washes need dynamic QR codes?

Not usually. Payment, membership and claim URLs are stable, so static codes pointing at pages you update work indefinitely. If you want per-bay scan analytics, that is a tracking question — see how-to-track guidance — not a reason to rent your URLs.