Space frames are three-dimensional frame structures which serve as roof or building structures. They usually consist of frame members (tubes) and nodes. At least two frame members are joined at a node.

Clamping connections in mullion/transom systems serve to fix facade elements/infill panels, such as glazing. They transmit loads acting perpendicular to these infill panels, usually wind or impact loads, to the supporting structure. They consist of pressure plate profiles, fasteners (e.g. screws) and supporting or base profiles. The screws are inserted into the predrilled holes in the pressure plate profiles and screwed into the screw channels of the supporting or base profiles.

T-connections in mullion/transom systems serve to transmit loads between the mullion and transom profiles. They usually consist of the mullion and transom profiles as well as fasteners (e.g. screws).

Mounting and racking systems for photovoltaic systems are needed to install these systems on the roof or a supporting structure.

Self-drilling or tapping screws and blind rivets are fasteners used in light metal construction. Unlike metric screws, they are not regulated by DIN EN 1090 or DIN EN 1993.

Mounting rails (C-rails) are most frequently found in concrete construction where they are concreted into the structure. However, mounting rails are also used in steel construction where they are directly welded to steel members. T-head bolts are inserted into the rails to fasten further steel members.

Lock bolts are most frequently used in wind turbines, because they are able to resist high tensioning loads and endure fatigue loading better than similar prestressed bolting assemblies in accordance with DIN EN 14399.

Regulatory framework

DIBt grants national technical approvals (abZ) for metal and composite metal products

• when they are not covered by a harmonised standard and
• when they deviate significantly from the Technical Building Rules (cf. MVV TB, in particular Chapter C 2) or
• when neither Technical Building Rules nor generally recognised technical rules exist (e.g. innovative products).

European Technical Assessments (ETAs) can also be issued for metal or composite metal products and kits which are not covered or not fully covered by a harmonised standard.

For construction techniques comprising these products or in this field, DIBt grants general construction technique permits (aBG) when there is no conclusive technical rule regarding design and execution.