Other Types of Glass. Glass Blocks

There are other types of glass which have been developed especially for certain situations. Shielding glass has a special coating to provide electronic shielding. Ultra-violet light-control glass has a special interlayer which reflects up to 98% of UV rays in sunlight. Various mirror-type glasses are used in surveillance situations, e.g. one-way glass (which requires specific lighting conditions) or Venetian striped mirrors with strips of silvering (any lighting conditions).

The term cast glass is given to machine-produced glass which has been given a surface texture by rolling. It is not clearly transparent – (1). Cast glass is used where clear transparency in not desired (bathroom, WC) and where a decorative effect is required. The ornamental aspects of cast glass are classified as clear and coloured ornamental glass, clear crude glass, clear and coloured wired glass, and clear and coloured ornamental wired glass. Almost all commercially available cast glass can be used in doubleglazing units – (1).

Normally, the structured side is placed outside in order to ensure a perfect edge seal. So that double-glazing units may be cleaned easily, the structured side is placed towards the cavity. This is possible only with lightly structured glass. Do not combine coloured cast glass with other coloured glasses such as float, armoured or laminated glass, or with coated, heat-absorbing or reflective glass.

Glass entrance screens consist of one or several glass doors, and the side and top panels. Other possibilities are sliding, folding, arched and half-round headed entrance screens. Various colours and glass structures are available. The dimensions of the doors are the same as those of the frame - (3) - (5) - When violently smashed, the glass disintegrates into a network of small crumbs which loosely hang together. Normal glass thicknesses of 10 or 12 mm are used, and stiffening ribs may be necessary, depending on the structural requirements.

Glass Blocks. Glass blocks are hollow units which consist of two sections melted and pressed together, thereby creating a sealed air cavity. Both surfaces can be made smooth and transparent, or very ornamental and almost opaque. Glass blocks can be obtained in different sizes, coated on the inside or outside, uncoated, or made of coloured glass. They can be used internally and externally, e.g. transparent screen walls and room dividers (also in gymnastic and sports halls), windows, lighting strips, balcony parapets and terrace walls. Glass blocks are fire-resistant up to G 60 or G 120 when used as a cavity wall with a maximum uninterrupted area of 3.5m², and can be built either vertically or horizontally. Glass blocks cannot be used in a load-bearing capacity.

Properties: good sound and thermal insulation; high light transmittance (up to 82%), depending on the design; can have translucent, light scattering and low dazzle properties; can also have enhanced resistance to impact and breakage. A glass block wall has good insulation properties: with cement mortar, к = 3.2W/m²K; with lightweight mortar, к = 2.9W/m²K.

Profiled glass is cast glass produced with a U-shaped profile. It is translucent, with an ornamentation on the outside surface of the profile, and conforms to the properties of cast glass.

Low maintenance requirements. Suitable for lift shafts and roof glazing. Rooms using this glass for fenestration are rendered dazzle-free.

Special types: Profilit-bronze, Cascade, Topas, Amethyst. Heat-absorbing glass Reglit and Profilit 'Plus 1.7' attain a к value of 1.8 W/m²K.

Solar-control glass (Type R, 'Bernstein'; Type P, 'Antisol'), which reflects and/or absorbs ultra-violet and infra-red radiation, can be used to protect delicate goods which are sensitive to UV radiation. The transmission of radiant energy into the room is reduced, as is the convection from the glazing, whilst the light transmission is maintained.

For glazing subject to impacts, e.g. in sports halls, Regulit SP2 or Profilit K22/60/7 without wire reinforcement should be used.

Regulit and Profilit are allowed as fire-resistant glass A 30. Normal and special profiles are also available reinforced with longitudinal wires.