How to Measure for a Glass Dog Gate: The Complete Step-by-Step Guide

For a swinging glass gate, the final glass width is based on the smallest opening measurement minus the clearances required by the selected hinge and latch system. Do not use a generic deduction when ordering custom glass; confirm the hardware manufacturer’s required gaps first. Because tempered safety glass cannot be cut, drilled, or trimmed after it is tempered, every dimension has to be final before fabrication begins.

This guide walks through every measurement, in order, with nothing assumed. Whether you have never held a tape measure against a doorway or you install glass for a living, you will be able to produce a measurement sheet your fabricator, like Fab Glass and Mirror, can build from.

1. Why Measuring a Glass Dog Gate Is Different from Measuring Anything Else

Tempering is a heat treatment: the glass is cut, drilled, notched, and polished to final shape, then heated to roughly 620 °C (1,150 °F) and rapidly cooled. That process locks the outer surfaces in compression, which is what makes the panel four to five times stronger than ordinary glass and what makes it break into small blunt granules instead of shards if it ever fails. It is also what makes the panel permanent. Score a tempered panel with a glass cutter and it does not cut, it disintegrates.

This is the same property that gives a glass pet gate its advantages. It does not warp in humidity, it does not yellow, it has no paint or laminate film to peel, and its hard surface resists the claw marks that shred a wooden or mesh gate within a season. Those benefits come from the material being finished, sealed, and final. So does the measuring requirement.

The practical rule: Every hole, notch, radius, and edge dimension must be correct on the order form, because none of them can be changed afterward. Measure three times. Order once.

2. Glossary: The Words Your Fabricator Will Use

Learn these six terms and the rest of the process becomes easy.

Term	What it means
Rough opening	The raw framed hole in the wall, before trim, jambs, or finished flooring. You will rarely measure this for a gate.
Finished opening	The hole as it exists on the day of installation, after drywall, jambs, casing, paint, and finished floor. This is what you measure.
Daylight opening	The visible clear space you can actually see through. For a trimmed doorway, the finished opening and daylight opening are the same.
Glass size	The actual dimensions the panel is cut to. Always smaller than the finished opening.
Reveal / gap	The deliberate air space between the glass edge and the wall or jamb.
Floor clearance	The vertical gap between the bottom edge of the glass and the finished floor.
Deduction	The total amount subtracted from the opening to arrive at the glass size. Deduction = hinge-side gap + latch-side gap.

One more distinction that trips people up: gate height is not the same as glass height. If you want the top of the gate to sit 36″ above the floor and you are leaving 2″ of floor clearance, the glass itself is 34″ tall.

3. Tools You Need

Essential

• Steel tape measure, 16 ft / 5 m or longer. Steel only. A cloth or fiberglass sewing tape stretches and will lie to you by 1/8″ or more.
• Spirit level, 4 ft / 1.2 m. A short torpedo level is not long enough to reveal a leaning wall.
• Torpedo level, 9″ for checking the floor and small surfaces.
• Pencil and painter’s tape for marking without damaging paint.
• A notebook or the worksheet at the end of this guide. Do not trust memory.
• A second person. Holding a tape flat across a 36″ opening alone introduces sag and angle error.

Strongly Recommended

• Stud finder (an electronic one that detects both wood and metal).
• Camera or phone photos catch things your tape misses.
• Framing square or combination square for checking corners.
• Calculator. Fraction arithmetic under a deadline is where errors are born.

For Awkward Openings

• Sliding bevel gauge for non-90° walls.
• Laser level for long or stepped runs.
• Contour gauge for profiled baseboards and moulded casings.

4. Before You Measure: Five Things to Settle First

Answer these before a tape comes out. Each one changes the numbers.

1. Is the Flooring Finished?

If new tile, hardwood, or carpet is going in after you order, your floor clearance will shrink by the thickness of that floor. Either wait, or measure from the existing subfloor and subtract the finished floor build-up (tile + thinset is typically 1/2″–3/4″; engineered wood with underlay 1/2″–5/8″; carpet with pad 1/2″–3/4″).

2. Is the Trim Staying?

Casing and baseboard reduce your clear opening. If you plan to remove or replace the casing, measure the opening as it will be after the work, not as it is today.

3. Which Way Should the Gate Swing?

This determines which side gets hinges, which side gets the latch, and where the handle lands. At the top of a staircase, the gate must swing away from the stairs, never out over the steps.

4. What Are the Walls Made Of?

Drywall over wood studs, plaster over lath, tile over cement board, and solid masonry each demand different anchors and different backing. This affects whether you can hang a heavy panel where you want it.

5. Mounted or Freestanding?

This guide covers wall- or post-mounted hinged glass gates, which is the dominant format. A freestanding glass panel has no opening to measure; you simply choose a panel size and check footprint clearance.

5. Step 1: Measure Your Dog

This is the step almost everyone skips, and it is the one that determines whether the gate actually works. Have your dog stand naturally on a level floor.

A. Shoulder height (withers height).

Measure from the floor to the top of the shoulder blades, not the top of the head. This is the standard way dog height is expressed.

B. Standing reach.

Encourage your dog to stand on their hind legs against a wall and mark the highest point their front paws reach. This is the number that predicts jumping and climbing, and for athletic breeds it is dramatically higher than shoulder height.

C. Chest height from the floor.

Measure from the floor to the lowest point of the chest/belly. Any gap under the gate smaller than this is one your dog cannot crawl through, though determined low-slung breeds will flatten themselves further than you expect.

D. Head width and head height.

The widest and tallest points of the skull. Side gaps and under-gaps must be small enough that a head cannot enter and become trapped.

E. Weight and temperament.

A 90 lb dog that leans on gates needs heavier hardware and solid backing than a 12 lb dog that respects boundaries.

Recommended Gate Height By Dog Size

Dog size	Typical shoulder height	Suggested gate height (floor to top of glass)
Toy / small (under 20 lb)	6″–12″	24″–30″
Medium (20–50 lb)	12″–20″	30″–36″
Large (50–90 lb)	20″–26″	36″–42″
Giant or athletic jumper	26″+	42″+ or full-height panel

Working Rule: The top of the gate should be at least 1.5× your dog’s shoulder height, and for any dog with a history of jumping, at or above their standing reach. Breeds bred for agility and hunting; Border Collies, Australian Shepherds, Huskies, Vizslas, Belgian Malinois, many terriers, routinely clear barriers far taller than their shoulder height suggests.

Maximum Safe Floor Clearance by Dog Size

Dog Size	Maximum Under-Gate Gap
Toy / small	1″ – 1.5″
Medium	1.5″ – 2″
Large	2″ – 3″
Low-slung breeds (Dachshund, Corgi, Basset)	Treat one size down
Household includes cats	1″ or less, and accept that cats may still pass

Two constraints are in tension here. Too large a gap and your dog crawls under. Too small a gap and the panel drags on carpet or catches on an uneven floor. Aim for the largest gap that still blocks your dog, then verify it clears your floor at every point of the swing.

6. Step 2: Identify and Prepare the Opening

Walk to the opening and do this before measuring anything:

1. Clear the area: Remove rugs, shoes, door stops, and anything within the future swing arc.
2. Clean both faces of the opening: A ridge of dried paint or a lump of caulk in the corner will throw a measurement by 1/16″ and will also prevent a panel from closing cleanly.
3. Decide your reference height: Mark the floor at the center of the opening with painter’s tape. This becomes datum zero.
4. Label your sides: Write “H” on tape at the hinge jamb and “L” at the latch jamb, as viewed from the room you’ll be standing in. Every later measurement refers back to these labels. Ambiguity about left and right is the single most common cause of a mirrored, unusable panel.

7. Step 3: Measure the Opening Width

Take three width measurements, hooking the tape on the inside face of one jamb and reading against the inside face of the other. Keep the tape perfectly horizontal, a tape angled downward reads long.

Measure at	Record as
Top: About 2″ below the head of the opening	W-Top
Middle: At your planned gate mid-height	W-Mid
Bottom: About 2″ above the finished floor, or just above the baseboard if the gate will sit above it	W-Bottom

Record all three to the nearest 1/16″ (or 1 mm). Do not round to the nearest inch and do not average them.

Then apply the rule: use the smallest of the three as your Controlling Width.

A panel sized to the widest point will not fit. A panel sized to the narrowest point always fits, and the difference shows up as a slightly larger reveal elsewhere, visually harmless.

Interpreting The Spread:

• Spread under 1/8″: Normal. Proceed without adjustment.
• Spread of 1/8″–3/8″: Common in older homes. Proceed, but increase your side gaps slightly so the taper is less visible and the gate never binds.
• Spread over 3/8″: Significant. Photograph the opening and discuss it with your fabricator. Options include a wider-cover wall mount, a filler strip, or shimming the hinge mounts.

Important: If your gate will sit above the baseboard (the common approach), measure W-Bottom above the baseboard, wall-to-wall, not between the baseboards. If the gate will extend down past the baseboard, then the baseboard-to-baseboard dimension is your controlling width at the bottom, and you will need either a notched panel or standoff spacers.

8. Step 4: Measure the Opening Height

Even though most glass dog gates are shorter than the opening, you still need height data for hardware placement, for floor slope, and because glass height must be exact.

Take three height measurements from the finished floor straight up:

Measure at	Record as
Hinge side: 2″ in from the hinge jamb	H-Hinge
Center	H-Center
Latch side: 2″ in from the latch jamb	H-Latch

If your opening has a header, measure to the underside of it. If it is an open hallway with no header, measure from the floor to your planned gate top instead.

Then measure the floor itself. Lay your 4 ft level across the opening, floor to floor, and note whether it reads level. If it does not, shim one end until it does and measure the shim height. Record this as Floor Fall.

Floor fall matters more than people expect. A floor that drops 1/2″ across a 34″ opening means a gate hung plumb will have a 1″ gap at one end and a 1/2″ gap at the other or it will scrape. Always set your floor clearance from the HIGH point of the floor, then confirm the gap at the low point is still small enough to stop your dog.

9. Step 5: Check Plumb, Level, and Square

Three quick checks. Two minutes. They prevent the most expensive mistakes.

Check A: Are the Jambs Plumb?

Hold your 4 ft level vertically against each jamb face. Note the direction and amount of lean. If a jamb leans more than 1/4″ over the height of your gate, the reveal will visibly taper, and a hinged gate may rub at one corner. In that case either increase the side gaps to absorb the lean, or ask about shimmed or adjustable wall brackets.

Check B: Is the Head Level?

Hold the level against the underside of the header. Record any fall. Only relevant if your gate reaches the header.

Check C: Is the Opening Square?

Measure both diagonals of the opening, bottom-left corner to top-right, then bottom-right to top-left.

• Diagonals within 1/8″ of each other: Square. No action needed.
• Diagonals differing 1/8″–3/8″: Mildly racked. Increase reveals.
• Diagonals differing more than 3/8″:  Significantly out of square. Send photos and the full set of numbers to your fabricator before ordering. A rectangular panel in a rhomboid opening leaves a wedge-shaped gap that may be wide enough for a small dog at one end.

10. Step 6: Check What’s Behind the Walls

A glass gate is heavy and it experiences repeated impact loads from a dog pushing against it. The mounting substrate is a structural question, not a detail.

Use a stud finder on the hinge jamb and map what you find. Wall studs are typically spaced 16″ or 24″ in the center. Door jambs are almost always backed by solid framing (the trimmer/jack stud), which is ideal. Open hallway walls may not have framing exactly where your hinges need to land.

Record the wall type:

Substrate	Notes for mounting
Drywall over wood framing	Ideal at a door jamb. Mid-wall locations may need blocking added between studs.
Drywall over steel studs	Needs toggle-type anchors rated for the load; steel studs flex more.
Plaster over wood lath	Brittle. Pre-drill carefully; anchor into the studs, never the lath.
Tile over cement board	Drilling requires a diamond bit and slow speed. Mark hole positions precisely, a mis-drilled tile is a repair job.
Solid brick, block, or concrete	Excellent strength. Requires masonry anchors and a hammer drill.
Newel post or stair post	Measure post width, depth, and shape; check whether the post is plumb and whether it is solidly anchored to the stair structure. A loose newel post will not hold a glass gate.

Measure and record the distance from the opening edge to the nearest stud center on both sides. Your fabricator needs this to confirm hinge placement or to specify a mounting plate that spans to solid backing.

11. Step 7: Map Obstructions and Swing Clearance

Stand in the opening and look at everything within an imaginary arc the width of your gate.

Measure and record the distance from the hinge jamb to:

• The nearest wall corner or return
• Any existing door and the arc of its swing
• Light switches, thermostats, outlets, and their cover plates
• Radiators, baseboard heaters, vents, and air returns
• Handrails, newel posts, and stair nosings
• Furniture that cannot move
• Door stops in the floor or on the wall

Then Check the Swing Arc:

Your gate needs clear space equal to its glass width plus the handle projection (typically 1″–2″) plus a safety margin. If your gate is 32″ wide and swings into a hallway that is 34″ deep before hitting a wall, you have 2″ of margin, workable, but tight.

Also Check the Vertical Swing Path:

If the floor rises in the direction of swing, a transition strip, a thicker rug, a threshold, the gate’s bottom edge must clear it at every point of the arc, not just when closed.

Measure Any Threshold or Transition Strip:

Its height, its width, and how far it sits from each jamb. A 1/2″ tall transition strip in a doorway effectively reduces your usable floor clearance to 1/2″ less than you calculated.

12. Step 8: Choose Your Gate Height and Floor Clearance

You now have everything needed to make these two decisions.

Gate Height (Floor to Top of Glass):

Use the table in Step 1. When in doubt, go taller. A gate that is too short is useless the first time your dog decides to test it; a gate that is slightly taller than necessary costs marginally more glass and nothing else. Also consider the humans: a gate above roughly 36″ becomes awkward to step over, so plan on always using the latch rather than stepping across.

Floor Clearance (Floor to Bottom of Glass):

Use the second table in Step 1, then verify against three things:

1. Floor Fall: Measure clearance from the high point.
2. Carpet Compression: Thick carpet needs 1/2″–3/4″ more clearance than hard floors so the gate swings freely.
3. Transition Strips: In the swing path.

A common, safe starting point for most households on hard flooring is 1.5″ to 2″.

13. Step 9: Calculate the Glass Size

Here is the arithmetic. Two formulas.

Glass Width

Glass Width = Controlling Width − (Hinge-Side Gap + Latch-Side Gap)

Glass Height

Glass Height = Desired Gate Height − Floor Clearance

Typical Gap Values

These are representative of hinged glass gates. Every hardware line is different, confirm the exact deduction with your supplier before ordering, because this number belongs to the hinge, not to the glass.

Hardware type	Typical hinge-side gap	Typical latch-side gap
Clamp-style wall-mount hinges (no glass cutout)	1/8″ – 1/4″	1/8″ – 3/16″
Through-hole wall-mount hinges (glass drilled)	1/8″ – 1/4″	1/8″ – 3/16″
Glass-to-glass hinges (gate to fixed panel)	3/16″ – 1/4″	1/8″ – 3/16″
Pivot hinges (top and bottom)	1/4″ – 3/8″	1/8″ – 1/4″
Fixed panel in U-channel	Add 1/4″–3/8″ per side for channel engagement	N/A

Note the last row carefully. A fixed panel that slides into a U-channel must be ordered larger than the opening so it engages inside the channel. A swinging panel must be ordered smaller. Mixing these up is a costly error.

Final Order: One Panel of Tempered Glass, 35 ⁷⁄₁₆” Wide × 32 ¼” High.

Sanity Checks Before You Commit

• Is the glass width smaller than the smallest opening width? (For a swinging gate, yes. Always.)
• Is the total under-gate gap at the low point of the floor still below your dog’s safe maximum?
• Is the top of the glass at or above your dog’s standing reach if they jump?
• Are the side gaps small enough (1/4″ or less) that a paw or jaw cannot wedge into them?
• Does the swing arc clear everything you mapped in Step 7?
• Have you written width first and height second, and labeled both? Glass is conventionally ordered width × height, and a transposed 32 × 36 becomes a useless 36 × 32.

14. Step 10: Locate the hardware and any glass cutouts

This is the step where the tempering rule bites hardest. There are two families of hinge hardware, and choosing between them changes your measuring burden entirely.

Clamp-Style Hardware: No Holes in the Glass

The hinge grips the glass edge between two gasketed jaws. Nothing is drilled. If your fabricator offers clamp hinges, choose them unless you have a reason not to. Your only measurements are the panel dimensions and the clamp positions on the wall, both of which are adjustable at install time. This is the low-risk path.

Through-Hole Hardware: Holes Drilled in the Glass

The hinge bolts through the panel. The holes must be drilled before tempering, which means their positions must be exact on the order form and can never be corrected.

If you are going this route, you need to specify:

• Hole diameter (supplied by the hardware manufacturer)
• Distance from the hinge edge to each hole center (the “edge distance”)
• Distance from the top edge to the top-hole center
• Distance from the bottom edge to the bottom hole center
• Center-to-center spacing between holes in the same hinge

Two rules govern hole placement in tempered glass:

1. Minimum edge distance: A hole’s edge should sit no closer to the glass edge than roughly twice the glass thickness, and many fabricators require more. A hole too near an edge creates a stress concentration that can cause the panel to shatter during tempering, or months later for no visible reason.
2. Minimum hole-to-hole spacing: Similar principle: keep at least twice the glass thickness of solid glass between adjacent holes.

Do not invent these numbers. Get the hardware manufacturer’s drilling template, and if possible, have your fabricator produce a shop drawing showing every hole dimensioned, and approve it in writing before fabrication starts. That signed drawing is your protection.

Latch And Strike

Measure and record:

• The latch height you want (usually aligned with the top hinge or at a comfortable hand height, 30″–36″ from the floor)
• The wall surface at the strike location, a strike anchored into hollow drywall with no backing will pull out
• Handle projection, how far the handle sticks out, which eats into your swing clearance

15. Step 11: Measure and Place the Breed Etching

A custom-etched breed silhouette does two jobs: it personalizes the gate, and it serves as a visibility marker. Large areas of clear glass at shin-to-chest height are a genuine walk-into hazard, particularly in low light, and building codes in many jurisdictions require visual indicators on full-height glass for exactly this reason. Treat the etching as a safety feature that happens to be beautiful.

Measurements To Take

1. Sightline Height: Stand where you normally approach the gate. The natural eye-catch zone sits roughly 30″–45″ from the floor for standing adults. If your gate is shorter than that, center the design vertically instead.

2. Available Design Field: Take your final glass dimensions and subtract margins:

• Design Field Width = Glass Width − (2 × side margin)
• Design Field Height = Glass Height − (top margin + bottom margin)

Use a minimum margin of 2″ on every edge. Increase it to 3″–4″ on any edge that carries hinges, clamps, or a handle, a silhouette that disappears behind a hinge plate looks like an accident.

3. Design Size: A breed silhouette typically reads best at 40%–60% of the design field width. Smaller and it looks lost on a large panel; larger and it crowds the edges.

4. Orientation and Viewing Side: Decide which room the design faces. Standard etching is applied to one face only, so the silhouette reads correctly from that side and slightly softened from the other. If both sides matter equally, a gate between two living spaces, ask whether double-sided or through-etching is available, and expect a price difference.

5. Multi-Panel Alignment: If you are ordering a gate plus fixed sidelights, decide whether the design is centered on the gate alone or composed across the whole assembly. If it spans panels, your fabricator needs the exact gap dimensions between panels so the artwork lines up.

A Note on Placement and Breed

For multi-dog households, a common approach is a single composition with each silhouette scaled to true relative size. If you want that, supply your fabricator with each dog’s shoulder height and body length so the proportions are accurate rather than generic.

16. Step 12: Confirm Thickness, Weight, and Edge Details

Thickness

Thickness	Common use	Character
5/16″ (8 mm)	Small gates, light dogs	Lightest; lowest hardware load
3/8″ (10 mm)	The standard for most dog gates	Best balance of rigidity, weight, and cost
1/2″ (12 mm)	Wide panels, large or powerful dogs	Noticeably more rigid; heavier hardware required

Thicker glass is not automatically better. It is heavier, which puts more load on your wall anchors and makes the gate swing with more momentum. Match thickness to panel size and dog strength.

Weight

Glass weighs approximately 13 lb per square foot per inch of thickness (2,500 kg/m³). Practical figures:

Thickness	Weight per sq ft	Weight per m²
5/16″ (8 mm)	~4.1 lb	~20 kg
3/8″ (10 mm)	~4.9 lb	~25 kg
1/2″ (12 mm)	~6.5 lb	~30 kg

Worked Example: A 36″ × 34″ panel is 8.5 sq ft. In 3/8″ glass that is about 42 lb. In 1/2″ it is about 55 lb. Now imagine that weight swinging, plus a 70 lb dog leaning on it. That is the load your wall anchors carry, which is why Step 6 matters.

Calculate your panel’s weight and tell your fabricator. It determines the hinge rating they specify.

Edge Finish and Corners

Neither changes your dimensions, but both should be on the order:

• Flat Polished Edge: Clean, square, modern. The usual choice.
• Pencil Polished Edge: Softly rounded. Slightly more forgiving to touch.
• Corner Radius: A small radius (typically 1/4″) on exposed corners reduces chip risk and is gentler on passing shins and paws.

Also confirm the safety glazing mark. Genuine tempered glass carries a permanent etched stamp in one corner citing the standard it meets, ANSI Z97.1 or CPSC 16 CFR 1201 in the United States, EN 12150 in Europe, and equivalent marks elsewhere. Ask where the stamp will be placed so it does not land in a visually prominent spot. If a supplier cannot tell you which standard their glass is certified to, that is a meaningful warning sign.

17. Special Situations

At The Top of a Staircase

The highest-stakes location, and the one with the strictest rules.

• The gate must swing away from the stairs, never out over them. A gate that opens toward the steps can push a person or dog backward down the flight.
• Mount the gate on the landing, set back from the top nosing, not overhanging the first step.
• Zero tolerance on the under-gate gap, a dog that slips under at the top of stairs is in immediate danger. Consider reducing your normal clearance.
• Measure the landing depth from the top nosing to the gate line and confirm it is deep enough to stand comfortably while operating the latch.
• Hardware mounting is critical. Confirm you are anchoring into structural framing or a properly secured newel post. Push the post firmly with your hand, if it moves at all, it needs to be re-secured before anything is mounted to it.

At The Bottom of a Staircase

Usually mounted between a wall and the newel post. Measure the post’s width and depth, check whether it is plumb (many are not), and note whether it is square or turned. Turned or tapered posts need a specific bracket and a recorded diameter at the exact mounting height.

Angled Or Non-Parallel Walls

If the two jambs are not parallel:

1. Measure the width at top, middle, and bottom as normal, the spread will be large and consistent.
2. Use a sliding bevel gauge to capture the actual angle, then transfer it to paper and measure it with a protractor.
3. Send photographs plus every dimension. Your fabricator will decide between an angled-cut panel, an adjustable bracket, or a filler piece.

Do not try to solve an angled opening with arithmetic alone. It is a case for professional review.

Archways And Curved Heads

Measure the springline: The height at which the curve begins. A standard rectangular gate sits entirely below the springline, so measure your width at that point and below. If you want the glass to follow the arch, your fabricator needs a physical template: tape paper across the opening, trace the curve, cut it out, and ship or photograph the template flat with a ruler in frame for scale.

Wide Openings Needing a Gate Plus Fixed Panel

For spans beyond roughly 40″–48″, a single swinging panel becomes heavy and unwieldy. The usual solution is one swinging gate plus one or more fixed panels.

Gate Width = Controlling Width − Fixed Panel Width(s) − Gaps at every joint

Count your joints carefully. A gate plus one fixed panel has three gaps: wall-to-fixed, fixed-to-gate, and gate-to-wall. Each gap must stay small enough that your dog cannot squeeze through, which in practice means keeping them at or under 1/4″.

Baseboard Interference

Three approaches, in order of preference:

1. Mount above the baseboard. Simplest. Measure your controlling width wall-to-wall above the baseboard height and set your floor clearance so the bottom of the glass sits at or above the baseboard top. Check that this clearance is still small enough for your dog.
2. Use standoff spacers. Small cylindrical spacers hold the hardware proud of the baseboard. Measure the baseboard’s projection from the wall face and order spacers slightly deeper.
3. Notch the glass. Possible, but the notch must be cut and radiused before tempering, it adds cost, and it introduces a stress point. Use only when the other two options fail.

Carpeted Floors

Thick carpet and pad compress under the gate and spring back, which can bind a swinging panel. Add 1/2″ to 3/4″ to your floor clearance versus a hard-floor installation, and verify that the resulting gap is still under your dog’s safe maximum. If it is not, consider mounting the gate to open in the direction where the floor is lower, or trimming carpet in the swing path.

18. Tolerances: How Exact Do You Need to Be?

Your measurements: Work to 1/16″ (1.5 mm). Finer than that is false precision, walls are not that consistent. Coarser than that accumulates into a gate that binds or leaves a dog-sized gap.

Fabrication Tolerance: Most glass shops hold cut size to roughly ±1/16″ (±1.5 mm) on dimensions and a similar figure on hole centers. Ask your supplier for their stated tolerance in writing.

Why This Matters: If you order a panel exactly 1/8″ narrower than the opening and the shop delivers at the wide end of tolerance while your opening is at the narrow end of your measurement error, you may have effectively zero clearance. Build your gaps with this in mind, a 3/16″ gap per side is more forgiving than 1/8″ and looks essentially identical.

When In Doubt, Err Toward a Slightly Smaller Panel. A gap slightly larger than planned is a cosmetic issue you can live with or address with a wider hardware cover. A panel that is too big is scrap.

19. The 12 Most Common Measuring Mistakes

1. Measuring in Only One Place: Openings are never perfectly parallel. Three measurements, always, and use the smallest.
2. Using the Largest Width Instead of the Smallest: The panel will not fit. This is the single most frequent fatal error.
3. Measuring the Rough Opening Instead of the Finished Opening: Trim and flooring will consume the difference.
4. Measuring Before the Flooring Goes In. Your clearance disappears with the new floor.
5. Transposing Width and Height. Always label. Always write width first.
6. Forgetting to Subtract Hardware Gaps. A panel cut to the exact opening size cannot swing, or cannot be installed at all.
7. Ignoring Floor Slope. The gap you measured at one end is not the gap at the other.
8. Using a Cloth Tape Measure. It stretches. Steel only.
9. Mixing Units Mid-Project. Pick inches or millimeters and stay there. A 1/8″ versus 3 mm mix-up compound is fast.
10. Not Checking Wall Substrate Before Ordering. You can end up with a beautiful panel and nowhere structurally sound to hang it.
11. Choosing Gate Height from Shoulder Height Instead of Standing Reach. Jumpers clear gates that look tall enough.
12. Assuming the Glass Can Be Adjusted on Site. It cannot. Tempered glass is finished glass.

Download our glass dog gate measurement worksheet.

20. What To Send Your Fabricator

A complete package prevents the back-and-forth that delays orders and causes errors.

Send:

1. The completed worksheet above.
2. A straight-on photograph of the whole opening, taken from about 6 ft back, with a tape measure extended across the opening and visible in frame.
3. Close-up photos of each jamb, top and bottom, showing trim profiles.
4. A photo of the floor across the opening, showing the finish and any transitions.
5. A photo of the baseboard where it meets the opening.
6. A photo of the swing area, showing what the gate will open into.
7. A photo of your dog standing next to something of known size, if you want the etching proportioned accurately.
8. Your hardware selection, or a request for their recommendation based on your panel weight.

Then Request, And Approve in Writing:

• A dimensioned shop drawing showing panel size, thickness, every hole and notch with its position, edge treatment, corner radii, the safety stamp location, and the etching artwork and placement.

Read that drawing carefully against your worksheet before you sign it. Once tempering begins, the panel is final.

21. READY TO MEASURE

Everything above reduces to a short sequence: measure your dog, measure the opening three times in each direction, check plumb and square, choose your height and clearance, subtract the hardware gaps, and get the drawing approved before anything is tempered.

Take the worksheet to the opening, work slowly, and write every number down. The gate you end up with will be one you install once and never think about again, no warping, no peeling, no scratched-up mesh, just a clear panel with your dog’s silhouette on it doing its job for the life of the house.

22. Frequently Asked Questions