For our roundhouse, we used these thatch panels. They're pre-made panels of thatch about 1.5 meters long. They've been sewn to a small piece of bamboo. They're stitched together with a piece of tree bark. And they're also flexible as you can see inside. We bent them around into the shape of a cone for the roof. This saved us several weeks of work. This whole roof was about $100 for the entire building. It took us one day instead of about one month.