How to Measure Windows for Custom Decals: Storefront Sizing, Panel Layout and Artwork Guide

Measure each individual glass pane rather than treating the entire storefront as one rectangle. Record the visible glass width and height, identify frames, mullions, doors, handles and other interruptions, then build the artwork around those real measurements before ordering custom window decals.

Large storefront windows can look like one continuous advertising surface from across the street, but they are rarely one uninterrupted piece of glass. Frames divide the storefront into separate panes, doors create additional sections, handles interrupt usable areas and architectural features can change where important artwork should appear.

That makes accurate measurement one of the most important steps in a custom window decal project. A design can look excellent on a computer screen and still fail when the dimensions do not correspond to the actual glass. A logo may cross a frame, a headline may disappear behind a door handle or a photograph may be divided at exactly the wrong point.

Pryntco’s Custom Window Decals can be ordered using the width and height required for the project. Because the dimensions are customized, the measurements supplied by the customer become part of the production plan rather than simply a reference.

This guide explains how to measure individual storefront windows, organize multi-panel graphics, account for doors and frames, plan artwork across several panes and identify measurement problems before the design reaches production.

1. How Should You Measure a Window for a Custom Decal?

Begin by measuring the actual glass area where the decal will be applied. Record the width and height of that individual pane rather than measuring the complete storefront from exterior edge to exterior edge.

For a simple single-pane window, the process may be straightforward. Measure horizontally across the usable glass and vertically from the upper usable edge to the lower usable edge.

For a storefront containing several panes, every section should be measured and recorded separately because seemingly identical windows are not always exactly the same size.

2. Should You Measure the Glass or the Window Frame?

Measure according to the area where the graphic will actually be installed. For a decal applied to glass, the usable glass area is normally the key dimension rather than the complete frame-to-frame exterior dimension of the storefront structure.

Window frames and mullions should still be documented because they affect the artwork layout, but they are not part of the printed glass graphic unless the project has been specifically planned otherwise.

Separating these measurements prevents a common mistake: designing one continuous graphic using the overall storefront width without accounting for the physical gaps between panes.

3. Why Should Every Window Pane Be Measured Separately?

Commercial storefronts often appear symmetrical even when the individual glass panels differ slightly in width or height.

One panel may be beside a door, another may sit between structural columns and another may contain different framing or hardware. Assuming that all sections are identical can create alignment problems during installation.

Measure every pane and assign it a clear label such as:

• Panel A – left storefront window
• Panel B – centre storefront window
• Panel C – glass entrance door
• Panel D – right storefront window

Those labels can then be matched to the corresponding artwork panels.

4. What Is the Best Way to Record Storefront Measurements?

Create a simple storefront diagram before entering measurements into the artwork. The drawing does not need to be architecturally perfect. Its purpose is to show the relationship between the panes.

Draw the storefront roughly as it appears from the primary viewing side and write the width and height inside each glass section.

Also mark:

• Doors
• Frames and mullions
• Door handles
• Locks
• Existing signs or markings
• Areas that should remain uncovered

This produces a much clearer production reference than sending a list of measurements with no explanation of where each number belongs.

5. Should You Measure in Inches or Feet?

Consistency matters more than which measuring unit you initially use. Many installers prefer taking detailed site measurements in inches because it is easy to record smaller differences accurately.

Pryntco’s current Window Decal ordering system accepts width and height dimensions in feet, so measurements can be converted when the final product configuration is entered.

Avoid switching randomly between feet, inches and decimal measurements within the same measurement sheet. Clearly label every number so there is no ambiguity when the artwork is prepared.

6. Should You Measure a Window More Than Once?

Yes. Critical dimensions should be checked at least twice before artwork is finalized.

A useful approach is to take the first complete set of measurements, then start again from the opposite side of the storefront and verify each pane independently.

If the numbers do not match, stop and determine why rather than averaging them automatically.

Possible causes include measuring from different reference points, including part of the frame on one attempt or discovering that the glass is not perfectly rectangular.

7. Should You Measure the Width at More Than One Point?

For large windows, checking the width near the top and bottom can reveal whether the opening or visible glass area changes slightly.

The same principle applies vertically. Checking both sides can help identify irregularities that are not obvious from a distance.

This becomes more important as the graphic grows larger because small measurement differences can become noticeable when several panels need to align visually.

If measurements vary enough to affect production or installation, provide the information rather than choosing one number without explanation.

8. What Is a Window Mullion?

A mullion is a structural or framing element that separates adjacent sections of glass. From a design perspective, it creates a visual gap in any artwork intended to span several windows.

A storefront may look like one large rectangle from across the street, but a photograph placed across four panels could contain three significant interruptions once installed.

These interruptions need to be incorporated intentionally into the artwork.

The goal is not always to hide the frame. It is to make sure important information is not accidentally destroyed by it.

9. How Do You Measure the Gap Between Window Panels?

If the artwork is intended to create one continuous visual composition across several panes, record the physical width of every frame or mullion separating them.

For example, a storefront plan may contain:

• 48-inch glass panel
• 2-inch frame
• 52-inch glass panel
• 2-inch frame
• 36-inch glass door

The two-inch gaps are not printed decal area, but they are part of the visual composition. The artwork needs to account for the distance that disappears between printed sections.

10. Should Artwork Continue Across Window Frames?

The visual composition can continue across several panes, but each pane should normally be treated as its own physical printed section.

Imagine a diagonal blue line travelling across three windows. The artwork can be designed so the line appears to continue naturally from one panel to the next even though the frame creates a visible break.

This is very different from simply slicing one image into equal sections without measuring the gaps.

Proper panel planning helps the completed storefront appear intentionally continuous when viewed from the intended distance.

11. What Should Never Be Split Across a Window Frame?

Avoid placing critical information directly across a mullion whenever possible.

That includes:

• Company names
• Phone numbers
• Website addresses
• QR codes
• Faces
• Small logos
• Important product details
• Calls to action

A large background shape can tolerate an interruption much better than a phone number or a person’s face.

If a major logo spans several panels, review the design at full storefront scale and ensure the gaps do not make the logo difficult to recognize.

12. How Should You Measure a Glass Door?

Treat the door as its own panel rather than including it inside the dimensions of the adjacent fixed window.

Measure the usable glass width and height and separately document the location of the door handle, lock, push plate or other hardware that affects the visual area.

Remember that the door moves. A graphic may look aligned with the surrounding storefront when the entrance is closed but appear separated when the door is open.

That does not mean doors should never carry graphics. It means the design needs to work as an independent section as well as part of the complete storefront.

13. How Do Door Handles Affect Window Decal Design?

Door handles can interrupt lettering, QR codes and graphic elements if they are ignored during artwork preparation.

Record the approximate location and occupied area of the handle rather than measuring only the complete glass dimensions.

For a branded door, consider keeping the most important information above, below or beside the hardware.

A customer should not need to visually reconstruct a phone number because a large metal handle crosses the middle of it.

14. Should Business Hours Go on the Main Window or the Door?

Either location can work depending on the storefront layout, but information customers need when standing at the entrance is often most useful near the door.

The key measurement consideration is whether the selected area remains visible when the door is open and whether hardware interferes with the wording.

Business hours should generally be treated differently from a large promotional headline because they are designed for close-range reading.

Give them a dedicated readable area rather than embedding them inside a large photograph.

15. How Should You Measure Windows With Existing Decals?

First decide whether the existing material will remain or be removed.

If the new graphic needs to fit around permanent lettering or another element, measure both the glass and the occupied area so the artwork can be planned around it.

Do not assume an old decal is positioned perfectly in the centre or that it can be used as a reliable measuring reference.

Measure from the physical glass boundaries and then document existing graphics as additional information.

16. What About Safety Markings or Other Required Window Elements?

If the storefront contains markings or other features that must remain visible, document them before designing the graphic.

The designer should know that these areas are unavailable rather than discovering the restriction during installation.

Requirements can vary by building, property and location, so any compliance-related restriction should be confirmed for the specific site rather than assumed from a generic decal guide.

Measurement planning should include all areas that cannot be covered, regardless of why they need to remain visible.

17. How Do You Measure a Multi-Panel Storefront?

Work systematically from one side to the other.

Once the individual dimensions are recorded, compare their combined span with an overall storefront measurement as a basic cross-check.

18. Why Should You Number Every Panel?

Panel numbering connects the site measurement, artwork file and installation sequence.

If a storefront has seven pieces of glass, naming files simply “window1-final,” “window2-final” and “new-window-final2” can become confusing quickly.

A clearer system might be:

• W01 – far left window
• W02 – centre-left window
• D01 – entrance door
• W03 – centre-right window
• W04 – far right window

Use the same identifiers on the measurement sheet and production artwork.

19. Should You Take Photos While Measuring?

Yes. Photos add context that measurements alone cannot provide.

Take one straight-on image showing the complete storefront and additional closer photos of each panel or unusual feature.

Useful photographs include:

• Complete storefront
• Each window pane
• Entrance door
• Handles and hardware
• Frames and mullions
• Existing graphics
• Areas blocked by fixtures or displays

The photos should support the measurements, not replace them. Perspective in photographs can distort dimensions.

20. Can You Measure a Storefront From a Photograph?

A photograph alone is generally not a reliable substitute for physical measurements because camera perspective, lens distortion and viewing angle can change perceived proportions.

A photo may be extremely useful for planning the artwork and creating a visual mockup, but production dimensions should come from confirmed measurements of the actual installation area.

If a reference object of known size appears in the image, it may help estimate proportions during early concept work, but estimated dimensions should not silently become final production dimensions.

21. How Do You Measure a Window That Is Too High to Reach Easily?

Do not take unnecessary risks to obtain a measurement. If the installation area cannot be accessed safely with the equipment and conditions available, arrange for someone equipped to measure it appropriately.

Do not substitute a guessed measurement simply because part of the glass is difficult to reach.

Large elevated storefront sections can influence both production and installation planning, so identifying access challenges early is useful information for the project.

22. How Do You Measure Irregularly Shaped Windows?

Rectangular width and height may not be enough for triangular, angled, arched or otherwise irregular glass.

Document the complete shape and identify all dimensions required to recreate it accurately. Depending on the geometry, that may include several widths, heights or corner relationships.

Photographs and a clearly labelled drawing become especially important for these projects.

If there is uncertainty about how an unusual shape should be supplied, discuss the configuration before preparing final production artwork rather than approximating the opening.

23. Should a Decal Cover the Entire Window?

Not necessarily. Full-window coverage is one option, but many effective storefront designs intentionally leave part of the glass uncovered.

Partial coverage may be useful when the business wants to:

• Preserve more interior visibility
• Maintain additional daylight
• Keep sightlines around an entrance
• Create a horizontal privacy band
• Use only the lower or upper portion for branding
• Keep the design visually lighter

If the decal covers only part of the glass, measure and record its intended position as well as its size.

24. How Do You Measure a Privacy Band Across Several Windows?

First choose the top and bottom height of the band relative to a consistent physical reference such as the floor or lower glass edge.

Then measure the width of each individual pane.

The band may appear continuous across the storefront, but the artwork still needs to account for every mullion and separate glass section.

Consistency is particularly important because even a small vertical difference between adjacent panels can be obvious when a straight horizontal band crosses several windows.

25. How Does Window Decal Material Affect the Measurement Plan?

The physical dimensions of the glass still need to be accurate regardless of material, but the desired window function can influence how much area is covered.

A solid decal creates continuous printed coverage across the selected area, while Window Perforation Decals can be considered when maintaining some view through the covered glass is important.

Pryntco’s Window Decals vs. Window Perforation guide explains the material decision in more detail.

26. Should You Choose Solid or Perforated Graphics Before Measuring?

You can measure the glass first, but the material decision should be made before artwork is finalized because the intended coverage may change.

A business choosing a solid graphic may decide to cover only a selected band to preserve visibility elsewhere. Another business may use perforated film across a much larger section because maintaining some outward visibility is part of the goal.

The measurement sheet should therefore document the complete glass, while the artwork plan identifies which part of that glass will actually receive graphics.

27. How Does Viewing Distance Affect the Window Layout?

Measurement tells you how much space exists. Viewing distance tells you how that space should be used.

A graphic viewed by pedestrians from a few feet away can contain more detail than a storefront intended to attract people across a parking lot or from passing vehicles.

For longer viewing distances:

• Use larger lettering
• Use one dominant message
• Keep the logo easy to recognize
• Use strong colour contrast
• Avoid long service lists
• Use one clear image or visual idea

More window area should not automatically mean more information.

28. How Should a Large Logo Be Split Across Multiple Windows?

Start by positioning the logo across a scaled diagram of the complete storefront, including the gaps between panes.

Then evaluate exactly where the mullions cross the logo.

A large geometric logo may tolerate several interruptions without losing recognition. A thin wordmark may not.

If a frame cuts directly through an important letter, consider shifting or resizing the logo rather than accepting the interruption simply because the mathematical centre of the storefront appears correct.

The visual centre and the architectural centre do not always need to be identical.

29. How Should Photography Be Divided Across Window Panels?

Photography requires careful cropping when it spans several windows.

Avoid placing important faces or product details directly behind mullions. A frame through someone’s eyes or through the centre of a product can make an otherwise excellent photograph look accidental.

Instead, position the image so the architectural gaps fall through less critical background areas whenever possible.

Large environmental photography often works better than tightly cropped portraits for multi-panel storefronts because there is more flexibility when determining where the image can be divided.

30. Should Every Window Have Different Artwork?

Not necessarily. A storefront can use several approaches:

• One continuous composition spanning several panes.
• Repeated branding with a similar layout on each pane.
• Individual messages where every window promotes a different product or service.
• Mixed layout with one large brand section and several supporting panels.

The measurement process remains essentially the same. What changes is how those dimensions are used when creating the artwork.

Choose the visual system before designing each panel independently.

31. How Do You Create a Storefront Artwork Map?

Build a scaled or proportionally accurate overview showing every glass pane in its correct order.

Include the physical gaps between panes so the designer can understand how the finished storefront will appear.

A useful overview may show:

• Panel identification
• Width and height
• Mullion width
• Door position
• Hardware
• Graphic coverage area
• Primary logo position
• Headline position

This master layout can then be separated into individual production panels once the composition is approved.

32. Why Should You Design the Entire Storefront Before Exporting Individual Panels?

Designing each window separately from the beginning can make the storefront feel fragmented.

A master composition allows colour, geometry, photography and branding to flow consistently across the architecture. Once that overall design works, it can be separated according to the actual pane measurements.

This is especially important for graphics containing diagonal lines, large photographs or logos spanning several windows.

Independent panels still need to work on their own, but they should also make sense as part of the complete storefront.

33. How Much Margin Should Important Text Have From Window Edges?

Do not place critical information directly against the edge of the visible glass or immediately beside a heavy frame.

The appropriate safe area depends on the specific artwork and production template, so the current design guidelines should be used when preparing the file.

From a visual perspective, additional breathing room is also useful. A phone number that almost touches a window frame may technically fit but still look crowded after installation.

Pryntco’s Window Decal artwork upload page provides the current design template and safe-line guidance after dimensions are selected.

34. Should You Add Extra Material to Your Measurements?

Do not change final production dimensions arbitrarily without understanding the intended installation method.

Different projects may require different approaches to trimming, alignment and final sizing, particularly when graphics cover large areas or several adjacent panes.

If extra production area, trimming allowance or another installation consideration is required, that should be coordinated with the printer or installer rather than added by guesswork.

The site measurement should remain an accurate record of the actual glass. Production adjustments can then be made deliberately from that reference.

35. Should You Measure Before or After Hiring an Installer?

For a straightforward small decal, businesses may handle the measurement process themselves. Large multi-panel storefront graphics benefit from involving the installation plan early.

Pryntco’s Window Graphics and Wallpaper Installation guide highlights individual panes, frames, handles, doors and installation location as factors that should be considered before the artwork is finalized.

If professional installation is planned, confirm who will be responsible for final site measurements before production. That avoids having different people work from conflicting dimensions.

36. What Are the Most Common Window Measuring Mistakes?

Most problems come from treating a complex storefront like one simple rectangle.

• Measuring the full storefront instead of each glass pane.
• Ignoring mullion widths when artwork spans several windows.
• Assuming identical-looking panes are identical sizes.
• Forgetting door handles, locks and hardware.
• Using photographs instead of confirmed dimensions.
• Mixing feet and inches without clear labels.
• Failing to number individual panels.
• Placing logos, faces or text across frames.
• Designing the graphics before documenting the storefront.
• Guessing unusual dimensions rather than verifying them.

Accurate measurement creates the foundation for everything that follows.

37. What Should You Check Before Ordering Custom Window Decals?

Review both the physical storefront and the artwork one final time before production.

Also verify contact information, spelling, QR codes, finishing selection and the intended installation side before the files are approved.

38. So, How Should You Measure Windows for Custom Decals?

Start with the individual panes. Measure the usable width and height of every section of glass and record each one separately rather than treating the storefront as one continuous rectangle.

Next, document everything that interrupts the graphic: mullions, frames, entrance doors, handles, locks, existing signage and areas that must remain uncovered. Measure the gaps between panels when the artwork is intended to appear continuous across the storefront.

Then create a labelled storefront map. Number every pane, add the confirmed measurements and use photographs to provide visual context. Build the complete artwork around that real architecture before separating the design into the individual production panels.

Most importantly, verify the measurements before production. A few additional minutes spent checking dimensions can prevent logos from being divided incorrectly, headlines from crossing frames and individual graphics from being prepared for the wrong pane.

Pryntco’s Custom Window Decals allow customers to enter the width and height needed for the project and currently offer matte and glossy finishing options. Businesses planning larger storefront installations can also explore Pryntco’s Large Format printing collection.

If the storefront contains several panes, unusual dimensions or installation considerations that are difficult to communicate through a standard online order, request a custom printing quote or contact Pryntco with the measurements and project details.