Glossary – our knowledge from A to Z

See: Joint permeability coefficient.

The property of a material to resist mechanical abrasive effects. Abrasion resistance is especially important for floor finishes.

This is the portion of the radiation, e.g. from the sun, that remains in the pane and heats up the glass. Coloured glasses absorb more than normal clear glass. Additional coatings can absorb more or less depending on the configuration. The absorption, transmission and reflection components must always add up to 100%.

A person – not from the production department – appointed by the manufacturer and a person appointed by the ordering party, or a person nominated in the official acceptance documentation, confirm the results of tests on the basis of specific tests.

When it is necessary to stay in a hotel, guest-house, etc. overnight, the costs are reimbursed and the full amount can be deducted before payment of tax and social security contributions. If meals (breakfast, lunch or dinner) are consumed in the accommodation, the costs of these are deducted because otherwise the expenses allowance cannot be paid. A lump sum is paid in the case of an overnight stay in a private household.

Formal recognition of the competence of a facility to perform certain tests or testing methods. Accreditation is a term used in DIN and ISO standards, e.g. in connection with testing centres or with the official authorisation of certification to ISO 9001.

A colourless, combustible, readily volatile liquid. Used as a solvent in paints, acetylene and plastics.

A reactive, colourless, highly explosive gas. Used as a fuel gas in welding and as a raw material for plastics.

Generally known as obscured glass. The etched surface does reduce reflections but at the same time has the effect of making all colours appear matt and pale. Today, this type of glass is therefore used only rarely for picture frames.

The application of a caustic substance enables lettering or motifs to be “engraved” on the surface of the glass. The ensuing etched surfaces have a matt finish, but the strength of the glass is not adversely affected. Highly aggressive, toxic hydrofluoric acid is used for etching glass surfaces.

Various methods can be used to improve the sound insulation properties of glazing. These methods include the use of special interlayers (PVB foil), laminated safety glass with an asymmetric configuration, a large cavity between the panes of insulating glass, possibly filled with a heavy gas, and glass with a lower strength. The construction of the elements supporting the glass also have an influence on the sound insulation. The characteristic variable for sound insulation is the weighted sound reduction index R.

This type of glass consists of two or more glass plies bonded together by acoustically effective polyvinyl butyral sheets (PVB-Si).

This product improves the sound insulation properties of glazing owing to its chemical composition, which is tuned to certain frequency ranges.

This is the distance between two parallel faces, which are mostly used as an interlocking connection for transferring a torque.

This is a highly transparent jointing technique for glass. Only a very thin layer of adhesive is required which is cured by being exposed to UV light. One problem is the loss of strength in the adhesive joint due to climate influences. Currently, acrylate adhesive joints are used mostly for subordinate joints.

Often referred to as Perspex, a trade name, this is a light-fast and weather-resistant synthetic material that can be bent by applying heat and resembles glass because of its transparency. It is available in all colours, is hard and resists breakage, but is easily scratched and is not resistant to solvents or fire.

Usually referred to by trade names such as Perspex or Plexiglass, polymethyl methacrylate (PMMA) is a synthetic, thermoplastic material with an appearance similar to glass.

The dimension on a workpiece or component that was actually measured.

A dimension measured on the building site or in the factory. It may deviate from the planned dimension or still lie within the permissible tolerances.

Work that was not originally included in the construction contract.

Adhesion is a bonded connection between different substances. The effect is based on the different powers of attraction between the individual molecules of the substances (molecular interaction).

A failure mode in a loadbearing adhesive joint. Here, the layer of adhesive breaks away from one of the items being bonded together. Mostly caused by inadequate preparation of the mating faces. An adhesion failure in an adhesive joint is not permissible according to current legislation.

Generic term for a bonding substance used for construction and other purposes for thousands of years.

Adhesive tape is the generic term for backing materials coated with an adhesive on one or both sides.

This is an adhesive tape without a backing, merely a thin film of adhesive that is protected on both sides by a waxed or siliconised protective paper prior to use.

A relatively lightweight highly porous mineral building material based on lime, lime-cement or cement mortar which becomes porous during a foaming process and is always autoclaved.

This is a machine with a platform that can be raised and lowered with a hydraulic or electromechanical mechanism. The platform is surrounded by a safety barrier with a means of access/egress. These machines use different raising/lowering mechanisms depending on the particular functions, e.g. moving arm, scissors lift, telescopic mast.

This was originally a colloquial term for an opaque type of glass in which the mixing of harmonious colours resulted in an appearance similar to marble. In Austria this type of glass was produced up until the 1960s.

Nitrogen is usually an undesirable tramp element in steels. In cold-formed sections, nitrogen segregates to dislocations in the crystal lattice where it causes unfavourable discontinuous yielding. One disadvantage of this is embrittlement of the steel, but this can be rectified by adding aluminium to form harmless aluminium nitrides.

The densest component and the best thermal insulation are useless when poor workmanship or poor detailing results in a construction that is not airtight. This not only increases the U-value (rising energy costs), but the leaks trigger a chain reaction: the resulting condensation leads to mould, which leads to damage to the building fabric over the long-term.

This is a milk glass that has been ground to give it a matt finish.

This is a self-adhesive, multi-ply sheet into which a network of wires has been embedded. The foil is retrofitted to the glass and acts as a glass breakage detector complying with the highest risk class.

Upon being damaged or broken, this type of glass sends a signal to an intruder alarm system. To do this, a network of very thin wires, forming part of an electric circuit, is embedded in the interlayer of laminated glass.

The network of fine wires embedded in the interlayer of laminated glass to form alarm glass. If the glass is damaged or broken, an intruder alarm is triggered.

Also known as aluminography, this is a type of offset printing process. However, in this process an aluminium plate is used instead of a lithographic stone because of the former’s lower weight.

A type of glass with a high silicon dioxide content and smaller amounts of alkali oxides, calcium oxide, magnesium oxide and aluminium trioxide.

This is formed when two glazing elements meet an angle in an SSGS façade. The omission of vertical framing members at this point results in a corner detail with maximum transparency. Building physics requirements place considerable demands on the design of an all-glass corner.

A glass construction in which the edges of the panes are partly or completely without frames.

In this type of façade with its large expanse of glass the loadbearing construction (e.g. of steel, aluminium, timber, etc.) is replaced by loadbearing glass members. This results in a further dematerialisation of the façade, an even more transparent, even lighter appearance.

A façade design principle in which the loadbearing parts are positioned internally and are therefore invisible from the outside. This effect is mostly achieved by using SSG. In contrast to true all-glass assemblies, there is still a loadbearing structure of timber, steel or aluminium.

In this type of roof with its large expanse of glass the loadbearing construction (e.g. of steel, aluminium, timber, etc.) is replaced by loadbearing glass members. This results in a further dematerialisation of the roof, an even more transparent, even lighter appearance, and allows a large amount of daylight to enter the interior.

This is a substance that is added to a metal in order to modify its material properties.

A thermochemical treatment for coating a workpiece with aluminium.

A chemical element with the symbol Al and atomic number 13. The abbreviation is derived from alumen, the Latin word for alum. In the periodic table of the elements aluminium belongs to the boron group, which was previously called the group of earth metals. Aluminium is the third most common element and the most common metal in the earth’s crust.

Aluminium alloys are produced by alloying aluminium with other metals. In most cases the base material is Al99,5 (EN AW-1050A).

A thin aluminium foil covering to an insulating material. This covering of aluminium makes the insulating material impermeable to vapour and is primarily used as a vapour barrier (the aluminium facing must be on the side adjacent to the room requiring installation).

Aluminium is a light metal and, owing to the thin layer of oxide that forms very quickly upon exposure to the air, has a matt, silvery grey appearance. It can be formed into complex sections by way of extrusion, and this is a great advantage when manufacturing hollow sections.

Colloquially known as metallic glass or glassy metal, this is a metallic material with a disordered structure at the atomic level. The arrangement of the atoms is very unusual for metals and results in a unique combination of physical properties. Amorphous metals are normally harder, more corrosion-resistant and stronger than normal metals, but they generally lack the malleability so characteristic of metals.

The unit of electric charge. 1 Ah is the quantity of charge that flows through a conductor in 1 h with a constant electric current of 1 A.

A component that is used for fixing a screw or object to masonry or concrete. The commonest form is the anchor made from polyamide, a thermoplastic. The first industrially manufactured anchors appeared in 1910.

Anchors are used to fix façade elements to the building structure, for instance.

Steel elements are used to anchor beams, brackets or other steel components to concrete elements. These consist of steel plates to which anchor bolts are welded which are cast into the concrete to improve the transfer of tensile and shear forces. The welded anchor bolts create an interlocking structural connection.

A hand-held electric power tool fitted with a fast-rotating circular abrasive disc. The angle grinder gets its name from the fact that the drive is at 90° to the abrasive disc.

An optical phenomenon that occurs with toughened safety glass. The stress zones that build up within the glass during cooling can lead to double refraction of the light, which manifests itself in the form of visible coloured rings. This phenomenon is clearly evident during certain lighting conditions and is also seen in vehicle windows.

This term embraces all heat treatment methods that are based on raising the temperature of a workpiece to a certain level (annealing temperature), holding it at that temperature for a certain length of time (short or long) followed by slow cooling. We distinguish between full, partial, recovery, recrystallisation and diffusion annealing, also inter- and self-annealing.

If annealing temperatures are not maintained, the result is an unintentional modification of the microstructure. Exceeding the annealing temperature substantially for an extended period of time will result in material that is damaged, possibly completely ruined.

Aluminium parts whose surfaces have been given a protective layer (consisting mainly of aluminium oxide) in an electrochemical process, the purpose of which can be primarily protective, decorative or functional.

A surface treatment method for creating a protective layer of oxide on aluminium by way of anodic oxidation.

Alloys in anodising quality are used in order to guarantee particular decorative effects or an especially uniform appearance. Such alloys are produced according to special methods.

Abbreviation for Analysis System, an FEM program suite for solving complex problems in structural mechanics. It is ideal for analysing glazing components. Comprehensive knowledge of FEM and component testing for calibrating the FEM models are essential.

A transparent or translucent product made from several plies of glass, with or without plastic plies, that prevents or at least delays a violent attack (glazing resistant to manual attack, bullet- and blast-resistant glazing).

Generally, steel reinforcement is provided to strengthen a concrete component, i.e. to provide concrete, which has a good compressive strength, with a tensile strength. Another application of this principle is the provision of supplementary reinforcement designed purely to prevent cracking of the concrete at exposed edges.

Raindrops falling on sheet metal cause noise. The anti-drumming coating is applied to the underside of the sheet metal; it cuts down the noise because it reduces the ensuing vibrations that cause the noise. This coating therefore has a sound-insulating effect.

Compared with conventional glass, this type of glass exhibits a lower degree of reflection. This property is achieved by applying a special coating. Anti-reflection glass is used to avoid disturbing reflective effects caused by lighting.

The high transparency of this type of glass permits an excellent view of objects behind the glass. The observer is hardly distracted by light reflections nor by reflections of the surroundings, and can perceive colours clearly and with excellent contrast.

The residual reflection from this type of glass is < 0.1% (with anti-reflection coating both sides). Potential applications: display areas, showcases, picture frames, shop windows.

A coloured, hand-crafted type of blown glass. It is primarily used for artistic purposes.

The intersection of three or more roof surfaces at one point.

This is the abbreviation for alkali-resistant glass.

This can be produced as a film, but is mostly produced in the form of fibres. Aramid fibres are golden yellow organic polyamides. They are characterised by their very high strength, high impact toughness, high elongation at failure, good vibration attenuation and their resistance to acids and alkalis.

A method of welding that uses coated wire electrodes. After initiating the electric arc, the molten wire is transferred to the main material in droplet form. The coating forms a slag that prevents the ingress of air and can introduce additional alloying elements. This method is often used on building sites and for welding root runs.

An arched roof consists of a curved roof surface only. The cross-section corresponds to a circular arc with an included angle < 180°. An arched roof is therefore flatter than a barrel-vault roof.

In the broadest sense, humankind’s involvement with the built environment. The methodical design and organisation of structures is the key purpose of architecture. There are many definitions of this term which assign various tasks, topics and meanings to architecture.

This is a colourless, extremely inert, monoatomic noble gas. Owing to its low thermal conductivity, one of its uses is as a thermally insulating filling between panes of insulating glass.

The sharp arrisses of a cut glass edge are ground to reduce the risk of injury; the simplest form of edge working in the glass industry.

Removing the sharp burrs from cut edges. The surface of the cut edge is not worked.

The dimensions of an existing component or one provided by another trade.

In industrial production this is the planned fitting together of components and/or subassemblies to form larger manufactured items.

This is a document issued for a construction product by a certification body. The construction product must comply with the relevant technical codes of practice, National Technical Approval, National Test Certificate or Individual Approval and be subjected to internal and external quality assurance measures during its manufacture.

A systematic, independent examination of an actual situation and comparison with a target requirement. This is carried out to assess the effectiveness of a quality assurance system or parts thereof.

This is an old name for milk glass with a pink sheen.

A -phase solid solution of iron. The term austenite is also applied to other face-centred cubic structures. One example is the shape memory alloys. Austenite is the primary structural component in many stainless steels.

A closable pressure vessel for the thermal treatment of materials at pressures above atmospheric pressure. In the glass industry autoclaves are used for producing panes of laminated glass. Subjected to high pressure and elevated temperatures, the interlayer bonds with the individual panes of glass to form laminated glass.

German abbreviation for tender, award of contract, billing (Ausschreibung, Vergabe, Abrechnung).

This is a type of glass with shimmering inclusions. It is given this name because of its similarity with goldstone, a gemstone, which is also known by the name of aventurine glass and which shimmers because it contains traces of iron oxide.

The average value of a predefined number of measurements at various points on the visible surface of an individual anodised component.

A three-dimensional representation of an object in which all parallel lines remain parallel and to scale (unlike a perspective, the lines of which converge).

A biennial international trade fair covering everything to do with glass. All aspects of glass production, processing and treatment are presented. One special feature is the presentation of innovative forms of structural glazing. seele, known as an innovator in this field, is always present with impressive exhibits.

This is a failure mode in residual loadbearing capacity tests and occurs in the region of the point fixings of panes of glass (mostly laminated safety glass made from toughened safety glass). Damage to a pane over a wide area means that the region around the point fixing becomes so soft that the fastener can slip through the hole drilled in the glass.