How to Make a Straw Roof

Identify the ideal building material for your roofing technique. Opt for straw, not hay because it contains fewer seeds, making it less attractive to rodents and other animals. Avoid rice straw, which is harder to work with, and opt instead for straw from wheat or rye. Use additional organic material, such as manure, compost or leaves, if you wish to add on a "living room" over the layer of straw bales.

Frame a low-pitched roof according to your house plans. Install a nearly flat roof if your climate has sufficiently low precipitation to accommodate the design. Use a generous roof overhang if you are building straw walls to keep rain from reaching the walls and keep snow from piling up near the walls. Construct the roof trusses to support a solid wooden deck. Lay a waterproof membrane over the wooden deck roof.

Line your roof structure with straw bales, setting one beside the next to completely cover the roof surface. Cut the twines of the bales, letting the straw loosen, as you lay the bales. Add a thin coat, 1 foot or less deep, of organic material such as manure or compost over the straw bales. Plant herbs, grasses, flowers or edibles over the organic material, according to Chelsea Green Publishing.

Add straw to your roof regularly between growing seasons. Lay manure or other organic material, such as loamy soil, over the straw each time. Maintain a roof thickness of at least 14 inches of straw for maximum insulation.