Common in Thailand thin strips of bamboo with a wind and tuck are used to fasten thatch panels to bamboo rafters. After just one year, some percentage of these bamboo ties start to break. After 2 years maybe half break. After 3 years almost all are broken. It seems a contributor to the failure is the winding part creates a weak spot on the bamboo tie where it is bent at sharp angles. Is there a way to fasten thatch panels that lasts more than just a few years? Looking to stay with natural fasteners--no plastic or steel.

A grass roof won't last more than tree years anyway. This isn't English thatch that will last 40 years. I tie with wire but that has to be removed when renewing the roofing

If doing it the Thai way you often don't even get 3 years. I know how they do it and that's why I am asking to see if anyone has gone beyond this. I get more than 3 years out of grass thatch panels and will mention some ideas for longevity for people's reference:

1. A high roof pitch sheds water more quickly increasing longevity. People advocate anywhere between 36-55 degrees absolute minimum for thatch. So 55 degrees would be the smallest pitch that would satisfy everyone. Higher is always better.
2. Space the thatch rows 5-20cm with denser always being better.
3. Notch the rafters to fix the panels from slipping and sliding in the wind. This keeps consistent thatch coverage otherwise there will be thick and thin areas.
4. Panels are laid with just enough column overlap so that the tie around the rafter can tie down both panels. No more and no less. Otherwise you are just wasting thatch with thick and thin areas around the columns.
5. Each panel has minimum 3 points of attachment--at each edge and center. This is achieved by properly spaced rafters. This prevents panels from breaking over time.

The first two items require more thatch to achieve longevity. The last three items are just about optimizing what you have to work with. A final note is there are other types of thatch that last longer. I have heard one called something like yaak (?) can last 10 or 20 years. It's a broad leaf.