The float glass process is the most common method of flat glass production in the world. This process basically involves melting silicate (sand), lime and soda in a furnace and floating it onto a large bed of molten tin, hence the name float glass. This mixture slowly solidifies over the molten tin as it enters the annealing oven where it travels along rollers under a controlled cooling process. From this point the glass emerges in one continuous ribbon and is then cut and further processed to customers’ needs. Float glass is also known as soda lime silicate glass as these are the major components used in manufacture.

Refer Section 9.1 and Section 9.2 Composition and Manufacture

1.1           CLEAR FLOAT

As the name suggests, clear float glass is transparent, offering high visible light transmittance (VLT).

Metro GlassTech offers a complete range of clear float glass products from 2 - 19mm thick. Thicker float glass is made, such as 25mm, but is not readily available in New Zealand.

Float glass products are sourced from quality float glass manufacturers including Guardian, Asahi and Pilkington. Clear float glass is imported in containers and is supplied in packs, cases and end-caps. Clear float can be processed into heat strengthened, toughened, laminated, curved glass and Insulating Glass Units.

> View example in the Gallery

1.2           EXTRA CLEAR FLOAT
                (LOW IRON)

Standard clear float glass has an inherent green tinge, which is more apparent when viewing the edge of the glass, or in stacks of glass panels. This is due to the iron content in the silicate (sand). Extra Clear low iron glasses contain approximately one quarter of the iron content of standard clear float glass, providing an extra clear glass that is crystal clear in appearance.

Extra Clear glass is ideal in decorative and furniture applications, showcases, showers, shop fronts and toughened glass entries. It can be used in rooflites and atrium glazing when solar control is not a factor. Extra Clear glass is ideal for applications requiring colour backing or painting due to high light transmittance and true colour appearance. Product trade names are Starphire, UltraWhite, Claritia and Diamant and they can be processed into heat strengthened, toughened laminated, curved glass and Insulating Glass Units.