Damage to the Wire Rope Systems

Now and then, there are damaged span wires on greenings. Mostly, the brackets are affected, which are bent or torn off the wall at the highest point of the flexural buckling - load. This might be caused by a mistake in the realisation of the project, meaning deficient or bad mounting, but oftentimes the problem lies in the planning, or even in the construction of the brackets, which would be the responsibility of the respective manufacturer. These kinds of problems oftentimes occur not until the warranty period is exceeded, due to the slow growth of the plants… On this site, pictures of damages and their causes will be explained, and you will learn how FassadenGrün prevents damage on its own products.

Damage to cables and mounts caused by excessive weight

Rust Damage

Some span wire systems are only zinc-coated (galvanised) and rather designed for the interior: Mounted in the exterior, they might rust, soon. Such elements are hardly qualified for facade greening. But also stainless steel brackets can rust, for instance in the case of curtain systems. Oftentimes, discolourations occur because the respective stainless steel is not sufficiently rust-proof for the exterior. 

Unpractical Span Wire Systems

If curtain systems, for instance, are used, which are designed for light loads only, static damage will be unavoidable. Due to the heavy load of a wall greening caused by storms, wet leaves, fruits and so forth, the brackets will soon be torn off. Even brackets, actually designed for metal bars, fail when clamping the cable, because the tension is much larger using cables instead of bars. Vandalism damage on the other hand, occurs especially on deficiently planned (horizontal) span wires due to the "climbing possibility" of a vandal.

Insufficient Co-ordination Plant - Climbing System

In the case of climbing systems it is necessary to state their suitability for certain plants. FassadenGrün-systems are divided into five structures. With the help of the climbing plants site, an assignment to particular structures is possible, which prevents overloading.

Wrong Climbing Technique

Usually, tight cables should not be overgrown with climbing plants and become "strangled" because of this. Otherwise, a tension of about 500 kg (3 mm-cable), or 1.000 kg (4 mm-cable) can occur and destroy the brackets. FassadenGrün refers to the difficulty of the right climbing technique - meaning a parallel "stock arrangement" in the case of prone climbers (Chinese wisteria, bittersweet, knotweed). Please look at the respective site on climbing plants.

Forced Transfer of Load Peaks

Span wires are multilaterally loaded. This starts with the pre-stress, later it is the load of the leaves, fruits, and stems which can reach 10 kilogramme per square metre and even double in case of wet leaves (after rain). Extreme loads of 50 kg/sq emerge from icing, from multiple glazes and wind pressure, especially in great heights and on corners of buildings. Many providers of span wires fasten the cables in such a way that in the case of load peaks (storm, icing, climbing, rebounding children’s balls, or the like) the abrupt, quite high tensions are transmitted into the brackets, compulsorily. If these brackets are rigid and do not "spring", they cannot hold the loads and are torn off, soon. Brackets from FassadenGrün are only slightly tightened by hand (without cable tensioner) and thus, are designed not totally rigid but slightly springy. All cross holders are equipped with an anti-slip protection, which means overloading is not completely, but only partially transmitted onto the brackets. The cables slip out slightly and can be tightened again.

Broad Wall Spacing

Broad wall spacing operates like a lever and generates a high flexing buckling-load, which can bend or tear off the bracket. FassadenGrün states exactly, which bracket is maximally suitable for a certain wall spacing.

Insufficient Fastening

Often various problems occur: The emerging tensions in a span wire are underestimated, or not taken seriously, and the shanks are disconnected or tapered in the diameter, in the area of the highest flexing buckling-load, at the transition into the wall bend. Or the fastening in the wall is not sufficiently placed. Brackets from FassadenGrün do not have a shank disconnection, or tapering. With the help of strong plugs they will be deeply and safely fastened in the wall.

Unpractical (curtain) system, torn off bracket with rust marks
Climbing plant support system - Damage
Unsuitable eye bolts / plugs and too broad wall spacing, which causes the eye bolt in the lower, heavily loaded part to be pulled out
Structure eyelets
Too much wall spacing, hooks are not deep enough in the plugs
Too much wall clearance with a holder
Vandalism: In the public area, cables should not be mounted horizontally up to a height of about 2 m, due to the "climbing effect" of possible vandals.
Wire rope damage due to vandalism
Stainless steel bracket with a from inside rusting (zinc-coated) metal plug: The problem here lies in the damaged coping, which leads water into the wall. This water drenches the wall and causes corrosion on the originally dry plug.
Climbing plant support system with rust
A wall bracket which was designed for bars, not for cable and is now loosened due to a risky greening (Chinese wisteria).
Wall mount: loosened anchoring on wall console
Corrosion of a zinc-coated metal plug caused by a non existing sealing of the drill hole, fraying of the bracket due to a compulsive transmission of load peaks
Corroded metal dowel
Corrosion on a zinc-coated wall bracket
Corrosion on zinc-coat
Too much wall spacing, too weakly dimensioned bracket.
Planning error
Overgrown by silver fleece vine and overwrought cables, overloaded brackets
Damaged wire rope
Cross bars in the lower area of a growth support might occasionally invite climbers and slacken, or bent like in the case of these climbing bars.
Base area
Spanned wire with broad wall spacing, forced transmission of load peaks.
Wire rope defect
Insufficient co-ordination of plant and climbing system, as well as wrong climbing technique
Damaged cable
Pulled out bracket caused by the wrong climbing technique (entwinement by Wisteria)
Damaged wall mount