A properly designed permanent construction can achieve a lifespan in excess of 20 years. The sustainability of a building is highly dependent on the design, the quality of material used, the use of the building and the environmental conditions of the location. Permanent structures will obviously last longer than non-permanent structures and the longevity of non-permanent structures is predominantly dependant on the maintenance, the utilisation intensity, and the erection and dismantling methods.
Our materials undergo intense internal testing throughout the entire production process and fulfil most of the commonly used quality test methods. A great example of longevity would be the Grand Stand Open-air Theatre in Elspe, Germany. Completed in 1978, this structure is one of the most advanced and spectacular tensile structures to this day, delighting visitors with its imposing steel beams, which support the membrane roof and suspending it over the 2,000m² space.
The project, designed by the engineering company Naumann & Dollansky, has protected approx. 4,500 spectators from possible adverse conditions during the daily programmed shows ever since. The 25 m high masts suspend the membrane roof so that an area of 100m could remain free of any obstacle.
The structure, due to permanent exposure to typical German climatic conditions and in particular strong wind ice and snow loads, is actually one of the most evident examples of the longevity properties of our materials. The material used is a MEHLER TEXNOLOGIES®
Type IV PVC-PES coated fabric. The residual mechanical resistance (tensile strength), when measured in year 2007, was 95% of the initial value.
This has to be considered an excellent performance due to several pre-conditions, good engineering, quality membrane material and excellent execution and maintenance tasks. There has been no request to replace the fabric to date. The membrane covering remains a safe and attractive eye-catching structure for everyone who visits the park.
The MEHLER TEXNOLOGIES®
membrane material is weather resistant and should provide many years of trouble free service. However, the fabric can be cut or torn and can be damaged by a sharp impact; it can be crushed if subjected to high localised ‘pinching’ loads, caused by bad design or by inappropriate clamping devices.
On structures of this type, the membrane is a structural part of the roof system, and not just a protective cover. It is mechanically pre-tensioned to provide a stable roof system capable of withstanding the design conditions of wind, sand and weather etc. However, if damaged, redistribution of the load can result in a concentration of stress that could cause a propagation of tears. Minor problems can become major ones if neglected.
One of the great advantages of the VALMEX® MEHATOP FR materials is that even if it is PVDF coated, it is perfectly weldable, without grinding the surface, and this can even be done on-site by means of hot-air gun tools. Depending on the project location (and the maintenance dedicated to the membrane covering) small quantities of dust and other polluting agents could deposit themselves on the surface, diminishing the natural beauty. Rain generally removes most of these particles, but when it gets to the stage that the majority of the particles remain on the surface and are easy to see then the surface is considered dirty.
This will help preserve the aesthetic characteristics of your project.