How to Measure Glass — Splashbacks, Shower Screens, Mirrors & Table Tops

The Golden Rules of Measuring Glass

1. Always measure in millimetres (mm). Our ordering system uses millimetres exclusively. A metre is 1000mm, a centimetre is 10mm.
2. Use a rigid steel tape measure. Fabric tapes stretch and give inaccurate readings. A good steel tape is the most important tool you have.
3. Measure three times. Walls are rarely perfectly square. Measure width at the top, middle, and bottom. Measure height on the left, centre, and right. Use the smallest measurement if they vary.
4. Glass cut too large won't fit. Glass cut too small leaves gaps. Better to measure conservatively — you can fill a small gap with silicone, but glass that's even 1mm too wide won't fit between walls.
5. Toughened glass cannot be trimmed. All dimensions and modifications (holes, cutouts, corner radii) must be 100% correct before we go into production. There is no adjustment after toughening.

Measuring for a Kitchen Splashback

A kitchen splashback is typically the area between your benchtop and overhead cabinets (or ceiling). This is one of the more complex measurements because it involves a confined space and often power outlets.

Step 1: Measure the width

Measure from wall to wall (or from the edge of a tile/return to the opposite wall, depending on your layout). Measure at three heights — at benchtop level, mid-height, and cabinet/ceiling level. Note the smallest measurement.

Step 2: Measure the height

Measure from the top of the benchtop surface (not from the floor) to the underside of the cabinet above. Measure at three points across the width. Use the smallest measurement.

Step 3: Allow for clearance

For splashbacks that fit between walls and under cabinets, subtract 3–5mm from each edge that will be against a wall or cabinet. This allows room for silicone sealant and minor wall unevenness. Do not allow clearance on exposed (visible) edges — those should be the finished size.

Step 4: Mark power outlet positions

If the splashback has power outlets, measure the position of each outlet from a reference edge — always from the bottom of the glass and one fixed side edge. Record the X (horizontal from side edge) and Y (vertical from bottom edge) coordinate to the centre of each cutout. Specify this when ordering.

Measuring for a Shower Screen Panel

Shower screens vary significantly depending on whether they're framed, semi-frameless, or frameless. The general principle is the same: measure the net glass size, not the rough opening.

Framed and semi-frameless systems

The glass fits into a channel or rebate in the frame. Measure the inside of the frame opening (rebate-to-rebate) and subtract the rebate depth on each side as specified by the frame manufacturer. Typically 10–15mm is removed from each rebated edge.

Frameless systems

For frameless shower screens using standoffs or hinges, the glass size is typically the finished panel size — the hardware is designed for a specific panel size. Measure the opening and check your hinge/standoff manufacturer's spec for any edge clearances required.

Holes for hinges or handles

Specify hole diameter (e.g. 35mm for a standard hinge) and location as an X/Y coordinate from the bottom-left corner of the glass panel. All holes must be in the tempering furnace before toughening — confirm hole positions carefully.

Measuring for a Mirror

Mirrors are usually simpler to measure because they sit against a wall or in a frame — there's rarely a confined space to fit into.

Bathroom mirror (wall-mounted)

Decide the finished size you want and order to that size. There's no need for clearance gaps — the mirror will be adhesive-mounted or on clips, so it doesn't need to fit into a tight opening. A common bathroom mirror might be the full width of the vanity cabinet (e.g. 900mm) × the desired height (e.g. 700mm).

Wardrobe mirror (door panel replacement)

Measure the inner rebate of the door frame — the space the glass sits into. Subtract the rebate depth on each side (usually 5–10mm per side, check the frame spec). Order to the net glass size, not the frame opening.

Gym wall mirror

Measure the wall area to be covered and divide into panel sizes. Standard mirror panels are usually no wider than 900–1200mm. We recommend leaving a 2–3mm gap between panels for expansion. Edge polish all visible edges.

Measuring for a Glass Table Top

Table tops are the easiest measurement — in most cases you're ordering to a target finished size, not fitting into an opening.

1. Measure the tabletop area or base you want the glass to cover.
2. Decide on any overhang (e.g. 50mm beyond the base on each side).
3. The final ordered size = base size + overhang on each side.
4. For replacement tops, measure the existing glass.

Common Measuring Mistakes to Avoid

• Measuring in centimetres and entering as mm — e.g. entering 60 when you mean 600mm. Always double-check your unit. A 60mm splashback is 6cm wide — very small.
• Not accounting for tile trim or beading — if there's a tile edge trim where the glass meets the tile, measure from the glass contact surface, not the wall surface.
• Measuring the rough opening for a frameless system — for frameless shower screens, the glass size is usually smaller than the opening by the amount the frame hardware specifies.
• Forgetting to specify holes before ordering — especially for toughened glass. Once it's in production, holes cannot be added.
• Using a tape that starts at 50mm — some tapes have a hooked end that starts at 50mm (the hook itself is 50mm). Always start from the zero end or compensate.