Single or multiple fastening of non-load-bearing systems
Guide for rear-ventilated facades – Part 3
Our guide for rear-ventilated facades has already discussed the design and advantages of a rear-ventilated facade and basic embedment concepts.
This section addresses the properties and special features of a single or multiple fastening of non-load-bearing systems, which also includes the rear-ventilated facade.
This section addresses the properties and special features of a single or multiple fastening of non-load-bearing systems, which also includes the rear-ventilated facade.
Non-load-bearing system
A non-load-bearing system is a construction which does not contribute to the stability of the building. If the embedment fails, the fastened construction falls down, but the building remains intact. Good examples of non-load-bearing systems are pipelines and ventilation lines, railings, suspended ceiling constructions, and last but not least, rear ventilated facades. In contrast, load-bearing systems are, for example, steel girders that serve as supports for ceilings.Single or multiple fastening
With a so-called multiple fastening system, the load is transferred to at least two adjacent fastening points in the event of a failure of one of the fastening points. A multiple fastening system therefore requires at least three fastening points, which are structurally connected to each other. A fastening point can only consist of one anchor, although several anchors can also be used for one fastening point. For instance, with an anchor plate.
Both the figures above show the difference between a single fastening, in the top image, and a multiple fastening, in the lower image. If the fastening point in the top image were to fail, the attachment would abruptly fall off, even if it consists of several anchors. With the multiple fastening system in the image below, optical failure initially occurs due to the redistribution of the load. The usability of the construction inevitably suffers as a result, but it is possible to secure and protect the construction.
If multiple fastening is not possible due to the existing conditions on the building, i.e. lintels, or for corner formation, it must be anchored with a single fastening system. There are different ways of doing this, depending on the substrate. There are some national approvals for single fastening with nylon anchors, but these are often limited to individual embedment substrates, e.g. concrete. Alternatively, through bolts or an injection system can be used. It is important that both the through bolts and the anchor rods are made of A4 stainless steel. For masonry, the only current option for single fastening is the use of injection anchors.
The next part of our guide for rear-ventilated facades deals with the correct selection and installation of plastic facade anchors.
If multiple fastening is not possible due to the existing conditions on the building, i.e. lintels, or for corner formation, it must be anchored with a single fastening system. There are different ways of doing this, depending on the substrate. There are some national approvals for single fastening with nylon anchors, but these are often limited to individual embedment substrates, e.g. concrete. Alternatively, through bolts or an injection system can be used. It is important that both the through bolts and the anchor rods are made of A4 stainless steel. For masonry, the only current option for single fastening is the use of injection anchors.
The next part of our guide for rear-ventilated facades deals with the correct selection and installation of plastic facade anchors.
