MITHS TO DISPEL:
The anti-hail system with elastic cords is better than the system with plates because it “unloads” the hail
The construction of anti-hail covers is often distinguished by how the nets are secured to the structure, and above all how they are fastened between the rows to make the system as a whole as effective as possible.
Leaving aside the solutions that can be considered naive and/or bizarre, there are two systems for securing the nets:
1) With plates
2) With elastic cords
The first system is the most commonly used and, as you can see in the image, creates a good fastening along the entire length of the covered row.
This way, when hail falls the net acts as a container and conveys the ice to the centre so that, in the event of large accumulations, it can partially fall to the ground.
The second system uses elastic cords to secure the net because it is thought that with the weight of the hail the elastic cord will stretch, allowing the sheet to unload the hail onto the ground. The basic principle is to discharge the weight of the hail off the structure to reduce the stress, preserving the stability of the entire system.
While conceptually intuitive and understandable, in practice this system has proven ineffective because, despite the elastic cords behaving as expected, the net isn’t rigid so it just acts as a large pouch that fills up with hail.
The pictures are worth a thousand words.
In practice this means that the desired unloading of the weight doesn’t occur, and so the structure is just as stressed as with the traditional plate system, if not more.
Even the elastic cord system with central fastening (also called V5) doesn’t drain off the hail, and so there is no benefit in adopting this solution.
In conclusion, it’s clear that THERE’S NO benefit in using the elastic cord system because, aside from not doing what it’s supposed to do, it costs more because of the elastic cords and their subsequent frequent maintenance due to rapid wear (average duration: 3-4 years).
Furthermore, you can’t just build a simple structure (so less expensive) hoping it won’t have to handle a lot of weight. Instead, you need a well-made, robust structure that can provide sufficient guarantees in any situation.
If you design, buy and use the right building materials then you’ll have a strong, stable structure able to support really big weights!
As we often say, our job is to guide the customer towards a conscious, safe and reliable choice!
Our experience is always at your service to help you in the best manner possible!