Vetiver Grass for Thatch
Vetiver grass makes an excellent thatch, it is long lasting and when used correctly is highly effective in both keeping the house dry and regulating temperature. There are two main methods of thatching. Asians style using vetiver panels, and European/African style where vetiver bundles are used. As temperatures increase a thatched roof might make a more comfortable dwelling than metal.
A guide to thatch construction in South Africa: GUIDE-TO-THATCH-CONSTRUCTION-IN-SOUTH-AFRICA1.pdf (sa-thatchers.co.za)
Here is a question — Vetiver thatch when used correctly will last up to 20 years. Could this be a way of storing atmospheric carbon captured by vetiver grass?