Hailproof building
Buildings are exposed to various natural hazards - not only in mountainous areas, but also on the Central Plateau. More than one third of the damage to buildings caused by natural events is due to hail.
In large parts of Switzerland, any given location is hit by hailstones with a diameter of two centimeters every five to ten years, and even by hailstones with a diameter of three centimeters or more every 20 to 50 years. Hail is a phenomenon that is still difficult to predict, despite intensive research. The fact is that hail damage is increasing. It is good to know that a large part of this damage can be avoided - through hail-proof construction.
Small grains, big damage
The impact of a hailstone exerts great forces - also on buildings: Hailstorms often cause damage that leads to costly repairs or consequential damage. In general, the goal must be to plan and construct buildings and facilities in a hazard-appropriate manner. By means of suitable measures, the vulnerability of the building envelope to natural hazards can be significantly reduced. Hail protection in particular should be considered in any renovation project. This is often possible with a small financial outlay.
Early planning, cost-effective measure
The earlier a protective measure is planned, the lower the costs will be. An overall manager is best able to safeguard the interests of the client. This also applies to the recognition of natural hazards, the planning of appropriate protective measures and, if necessary, the involvement of suitable specialists. In addition to the overall manager's duty to provide information, it is just as important for the client to have the prevention issue clarified in the early stages. The architect is often the first point of contact for the client. In the interaction of the building owner, the planner as well as the authorities, the goals of the building protection from natural hazards can be achieved.
New SIA documentation
This year, for the first time, a complete documentation on design and planning with natural hazards in building construction is available. It deals with the natural hazards hail, storm, snow, flood, landslide, avalanche, rockfall, debris flow and earthquake. The clearly structured work illustrates the comprehensive approach that is indispensable for efficient construction in line with natural hazards (available from the sia Shop). Published in 2019, the documentation supplements SIA Standards 112 with conceptual solutions, among other things.
Material selection decisive
When it comes to hail protection, the choice of materials plays the most important role. Tested hail-proof building materials guarantee hail protection from the moment the building is handed over. Subsequent replacement of building materials after a damage event is also often possible with a small financial outlay. Glass, for example, is more resistant than plastic, especially when aging is taken into account. In addition to resistant building components, there is the possibility of constructive hail protection. For example, canopies protect the facade or fine-mesh protective plastic skylight domes.
Find suitable building materials
On the online platform hailregister.ch the corresponding components for the entire building envelope are clearly listed. The products listed have been tested for their hail resistance by recognized test centers. During the tests, the tester shoots standardized ice balls at the potential weak points on the component. According to a defined test arrangement, the component is repeatedly shot at potential weak points with ice balls of a specific diameter. If the component is still intact after such a series of shots, it has passed the test for the respective class. For example, hail resistance 3 (HW 3) means that the tested product is not damaged when hit with hailstones three centimeters in diameter.
Information: Association of Cantonal Fire Insurers VKF, Martin Jordi, Bern, Tel. 031 320 22 84, www.schutz-vor-naturgefahren.ch
Another article Hageschutzsystem can be found here.
