Thanks everyone for help with the thatching, I still like the idea of using mangled up balsa if I can persude John to have a go at it, or even paperclaying the roof and etching and roughing it up but if all else fails look what i remembered I had today!! While putting loads of the childrens things in the loft I came across an old mattress that we bought for Lacey. This was a really expensive one made from coconut fibre filling which is supposed to be the safest.
I had a quick look on ebay to see if they held their value before I tore into it, knowing it cost us about £60, but they dont seem to get bids as most people prefer to own a brand new mattress for each child nowadays.
So all that money we paid will pay off miniwise as i can rip it apart and use the fibres for thatching.
Woohoo, great to find a use for something we would have put in the tip eh!!!
Lets hope it works