Glossary – our knowledge from A to Z

The so-called b-factor (= shading coefficient) is often specified as well as the g-value (= total energy transmittance) for an insulating glass unit.

Simple equations for manual calculations, based on linear plate theory, for determining stresses and deflections in plates subjected to bending (i.e. out-of-plane) action effects.

This is made from a material that does not adhere to silicone so that it can be used in a silicone joint to ensure that the silicone does not adhere to three sides.

On a mortise lock, the distance from the centre of the handle-bar to the front face of the gain. This dimension is specified in millimetres and is important for ordering and installing mortise locks.

In this test a ball machine fires two types of ball at the glazing at angles of 45° or 90°. In order to pass the test, the glazing may not be damaged.

The ball-drop test is a standardised testing procedure for assigning laminated safety glass to the classes A1 to A3. The test involves allowing a steel ball to fall onto the glazing from various heights.

A safety barrier to prevent persons falling from a higher to a lower level. With either infill panels made from a suitable material (including glass) or individual, possibly ornamented, posts (balusters) made from wood or stone.

A process in which metal parts are placed in a rotating drum to improve the quality of the surface and/or remove burrs.

A roof form in which the roof surface corresponds to a half-cylinder. As the roof pitch at the middle is equal to zero, waterproofing problems can occur at this point.

Barrier-free building is a designation for the design and construction of buildings and external areas so that they may be used without limitation by all people, i.e. also those who have some disability.

This is the glass produced directly from the glass melt. Only after cutting to size, drilling, edge working and other processing is the glass suitable for its intended purpose. Also known as primary glass.

This is the side of a piece of float glass that was in contact with the molten tin during its manufacture. A special UV lamp is used to determine which side is the bath side; the surface of the glass appears milky in ultraviolet light. Experimental studies have revealed poorer strength values in loadbearing adhesive joins when the bath side is used.

The designation for that side of float glass that was in contact with the bath of molten tin during production. This side is characterised by lower mechanical strength but better chemical resistance. It can be detected by shining UV light onto the glass, which causes the bath side to fluoresce slightly.

A style in architecture and design that is equivalent to that of the modern movement. In this style the individual parts of a building were separated according to their function, e.g. the façade was no longer a loadbearing component and therefore could be designed as required. Such a design feature is known today as a curtain wall in modern buildings with glass façades.

Currently the economic extraction of aluminium on an industrial scale is only possible with bauxite. Bauxite is mainly obtained from open-cast mines. The most important producing countries are Australia, China and Brazil. In contrast to other raw materials, there are still adequate deposits of bauxite available.

Named after the Austrian chemist Carl Josef Bayer, this method of obtaining aluminium involves mixing the crushed bauxite with aqueous sodium hydroxide solution, which is caused to react at a temperature of approx. 150 °C in order to separate it from impurities such as iron oxide and silicon oxide.

This is a plastic or steel cable contained in a membrane pocket which, because it is thicker than the membrane, can be secured against pull-out in a retaining member. Membrane structures can therefore be secured in position.

This is a type of milk glass in which bone ash is added to the glass melt to achieve the milky appearance of the glass.

This is a conical metal ring that can be loaded in the axial direction. Static and dynamic loads are possible. The advantage of a Belleville washer is that large forces can be accommodated in a very small space, for example.

Bending involves the plastic deformation of a material by way of bending forces. This process is used in order to shape sheets, tubes, sections, wires and bars.

When forming steel by way of bending, crimping or folding, a minimum radius inherent to the particular material must be adhered to so that the steel does not tear at the surface.

A strength characteristic that is especially important for brittle materials (grey cast iron). The specimen is supported at both ends and loaded in the middle. The bending strength is not necessary for approval.

The ability of a building component to accommodate and transfer bending moments. The bending strength of a steel beam depends on its second moment of area. Several beams can meet at a node and it may be necessary to transfer a moment across the node.

Pane of glass bent to a predetermined shape with the aid of heat. Also known as curved glass.

A special pitched roof form in which one roof surface is at a steeper angle than the other.

One chamfer along each side of the glass.

A substance that that bonds together finely distributed solids (e.g. powders) or bonds them to a substrate. Binders are usually added in liquid form to the fillers to be bonded.

A mesh or grating that prevents the entry of birds.

Bitumen paint is used to protect building components (e.g. external basement walls) against moisture, metals (e.g. iron, steel) against corrosion or timber against weathering.

Glass types with a blast resistance classification protect persons and property against the effects of explosives. Such glass types are in the form of multi-ply laminated glass. Explosion-resistant glazing is allocated to classes D1 to D3 in the DIN standard, classes ER 1 to ER 4 according to EN 13541.

A by-product that ensues during the production of crude steel in a blastfurnace. It consists of the impurities in the ore (gangue), coke ash and additives (burden).

As a rule, a façade traces, or rather reveals, the segmentation or the cross-sectional form of the building behind it. However, a blind façade conceals the constructional nature of the building.

This is the background colouring to a large area of glass. The blotch colour is applied with a brush. Afterwards the surface is dabbed with a wad of material. The intention of this process is to create a matt, uniform distribution of the colour.

This test enables an assessment of the airtightness of a residential building. With the windows and external doors closed, a fan is used to force air into or out of the building with a 50 Pa pressure difference. The amount of air that escapes is measured. The result is the number of air changes per hour (n50).

The removal of excess carbon from molten or red-hot iron through the introduction of oxygen. Blowing with pure oxygen accelerates the steelmaking process and results in better steel grades.

A hollow steel pipe 100–150 cm long with one wide end for picking up the glass melt and a mouthpiece at the other end into which the glass-maker blows.

The blue colour is created by adding iron oxide and/or cobalt. Blue glass is relatively common; besides products for the building industry, it is used for decorative household objects.

This type of coloured glass is produced by adding small amounts of metal oxides to the melt. These reduce the light transmission and also the solar gains through the glass. The energy absorption of body-tinted glass is relatively high, which makes this type of glass vulnerable to thermal stresses. The panes are therefore usually toughened in order to prevent breakage caused by thermal stresses.

This is a type of glass that is resistant to chemicals and high temperatures. It is used for glass apparatus in laboratories and in chemical processes.

Hand-made, circular pane of glass with a diameter of 5–15 cm. It is used for leaded lights (bull’s eye or bullion).

A pair of different samples that specify the limits between which a colour or texture is acceptable in order to satisfy the approval criteria for erection. Boundary samples are used for anodised finishes, for example.

A climate-induced effect that affects insulating glass units. Due to pressure and/or temperature differences, the volume of gas in the cavity of an insulating glass units either expands or contracts. The individual panes of glass therefore move closer together or further apart. This aspect must be considered in the structural design of insulating glass units.

In a framework a brace is a diagonal member that increases the stiffness.

This is required to stiffen and stabilise a loadbearing structure. It must transfer the horizontal loads to the foundations or to other components. We distinguish between horizontal bracing in roofs or floor structures, and vertical bracing in walls.

Brass is an alloy of copper and zinc. It is somewhat harder than pure copper and in contrast to steel and aluminium alloys heat treatment does not render it susceptible to age-hardening.

This is essentially the same as a leaded light, except that brass-covered lead cames are used instead of pure lead cames. This improves the appearance compared to standard leaded lights.

Building Research Establishment Environmental Assessment Method. A British evaluation system for certifying the total performance of a building relevant to the environment and the guidelines for design and management processes. BREEAM is the most common certification system on the international market and includes local adaptations for the Gulf region or the rest of Europe, for instance.

These are special raised setting blocks with a ventilation channel underneath which guarantees vapour pressure equalisation around the periphery of the glass.

This is produced from hot-rolled, occasionally forged, steel through descaling and subsequent cold-forming. It has a shiny, smooth surface and much better dimensional accuracy than hot-formed steel products.

A hardness testing method developed in 1900 by the Swedish engineer Johan August Brinell. It is used for soft to medium-hard metals, e.g. unalloyed engineering steels or aluminium alloys, also timber and materials with an irregular microstructure, e.g. cast iron. The test involves pressing a hard steel ball into the surface of the material to be tested with a defined testing force.

A typical failure mode for glass. Local stress peaks lead to abrupt failure of the component without warning, e.g. in the case of severe deformations.

Bronze is an alloy of copper that usually contains tin, but sometimes other metals as well. It was one of the earliest alloys produced by mankind. Today, sieve meshes, bearing bushes, fittings and the screws of ships and boats are made from bronze.

The bronze colour is produced by adding selenium. Bronze-tinted glass is frequently used for attenuating brightness or in interior architecture for decorative purposes.

A computer program for viewing Internet pages or other documents and data.

German abbreviation for floor-mounted door closer (Bodentürschließer).

A loss of stability, right up to complete failure, of straight or minimally curved linear members or beams due to the effect of compressive forces, whose line of action coincides with the axis of the member, and/or bending moments. The slenderness of a component is critical for the risk of buckling.

The discipline that deals with the architecture of buildings that rise above ground level.

In many countries a building authority is responsible for approving and monitoring certain construction projects that require approval/permission. The prime task is inspecting the execution of the construction approved according to an approval issued with corresponding stipulations.

In architecture or construction the designation for a discrete part of a structure or building.

This is the term for the outer “hull” of a building: the façades plus the roof. There are sometimes no distinct divisions, making it difficult to tell where a façade ends and the roof begins.

Building physics is a branch of physics that is concerned with the physical properties of building materials, components and buildings themselves. The building physics properties of materials and components are laid down in standards and regulations. Building physics can be subdivided into four main areas: fire protection, thermal insulation, moisture control and sound insulation.

In a bullet-resistance test, appropriate weapons are used to fire suitable projectiles at the glass in order to establish to what extent the glass is penetrated. The test also involves checking whether splinters of glass are ejected from the rear surface of the glass even if a projectile does not penetrate the glass. Swiss standard SIA 331.511 applies, which is equivalent to EN 1063. There are five classes, C1 to C5.

Laminated safety glass that can withstand impacts, projectiles and blasts and is therefore suitable for protecting persons and property.

A mixture of iron ore, fluxes and possibly scrap that is fed through the throat into the blastfurnace.

Burnishing is used to create a protective layer on surfaces containing iron in order to reduce corrosion. Immersing the workpieces in acidic or alkaline solutions or salt baths causes the formation of jet black mixed iron oxide layers. Burnishing is not a coating treatment.

A door hinge that is mounted in the rebate so that from the outside only a narrow cylinder is visible when the door is closed.

A butt joint is formed when two panes of glass are bonded together either in line or at an angle. The edge of one pane is therefore butted up against the edge or surface of the other.

A quality test for structural glazing silicone. This test has to be carried out upon starting up mixing equipment and after mixing two-part compounds. The purpose of this test is to check the quality of the mixing of the silicone.

The hermetic edge seal to an insulating glass unit.