Specifications for Glass Fittings

Glass Types

Clear float glass

Clear float glass is the most commonly used type of glass. It has a very slight green tint due to the iron content in the sand (silica), which is the main component of glass. When paint is applied to the glass this green tint is visible along with the paint colour. Graphic Glass has developed a colour compensation scheme to minimise the unwanted effects of clear float glass. However for lighter colours such as whites we recommend Low Iron Glass.

Clear Float glass comes in 3, 4, 5, 6, 8, 10, 12, 15 & 19 mm thickness.

Low iron glass

The more expensive Low Iron Glass is the most optically clear glass, Highly recommended for lighter colours, pastels, creams, pure white, light yellows. It contains less than 15% of the iron content found in float glass, giving it an ultra clear appearance. Low iron glass comes in 5 and 10 mm thickness.


The available hole sizes are 5, 6, 7, 8, 10, 12, 14, 16, 18, 20, 21, 22, 23, 26, 30, 32, 40, 50, 63 mm

Polishing edges come in Rough Arris, Flat Polish, 22 and 45 Mitre, Half Bull nose, Round Polish.

Odd shapes and curves are cut with a template. A margin of 1.5 mm should be allowed for between the glass and the edge of a cupboard, window sill or other object. For toughened Glass with cut-outs and/or notches this margin might have to be slightly more to allow for rounding of corners due to the toughening process.

Toughening process

Toughened glass maximum lengths

Glass thickness Glass length
4 mm 2438 mm
5 mm 3251 mm
6 mm 3658 mm

Minimum size is 100 x 300 mm, or 280 mm dia.

If the glass becomes a strip then the ratio 1 to 15 needs to be applied. If exceeded the glass will curve in the toughening process.

Bench and table top requirements

Recommended minimum glass thickness: supported by MDF 8 mm toughened and 10 mm Annealed glass

Unsupported spans

Size required thickness

Size Toughened Glass Annealed Glass
0.5 sqm 5 mm 10 mm
1.0 sqm 8 mm 15 mm
1.5 sqm 10 mm 19 mm

Gas hob requirements

If you install a gas hob then toughened glass is allowed as a non combustible surface to be attached to the gib board behind it.

However, if your gas hob elements are closer than 200 mm to the surface of the glass then a heat absorbent board has to be used instead of conventional gib or fire rated gib. The minimum thickness is 10mm. The area that this heat absorbing material has to cover is a strip, which runs 150 mm outside the most left to the most right element and 150 mm high from the bench up the wall. This rule applies also for tiles and stain - less steel.