Can I build a straw bale house in Spain?

Hi does anyone know if we can build a straw bale house- without planning in the La Alpujarra (Orgiva) Spain? It would be on a raised wooden platform standing on stilts so would have no real foundations. Would we need to apply for planning is the biggest thing?! Technically it doesn't have a mive footprint. Also would only be a single storey with a slightly pitched roof, and using as many natural materials from our surrounding as possible. Cheers.