Straw Bale House Roof

The straw bale roof constructed by dr zhang and blue mountains straw bale builder jason dash only took one day to erect.

Straw bale house roof.

It is built with straw bale walls and limestone plaster log roof rafters an. While cement stucco is convenient and low maintenance it can cause moisture problems once it cracks and may actually keep the bale wall from drying properly. For straw bale this can pose a problem in keeping the walls free from direct moisture. There are two general styles of straw bale construction.

The papercrete is completely unsealed and thus breathable. A breathable strawbale vault is a difficult proposition. Post and beam construction is where a structural frame is built and the bales are then placed into that frame as insulation. All straw bale houses need a layer of plaster on the outside to keep water out.

Most straw bale builders use clay based earthen plasters or lime plaster which require regular reapplication. When attaching a straw bale addition to an existing house the biggest concern is to make sure that the two structures are tied together well. Today insulated homes usually have r 20 in the walls and many old homes have r 14 for insulation or considerably less. As i look at this i think a roof would almost be better with loose fill chopped straw inside of a 2 6 roof framework.

The weight of bales within a roof has to be a very serious consideration. A good time to use this roof is obviously when the budget is tight or if you want a larger exposed side of the structure as in a greenhouse or in cooler climates. The easiest way to do this is with expanded metal lath at each course. Video tour of an incredible underground hobbit home that is completely off grid.

The bales have no structural value for the loads of the building which are all carried by the structural frame. A good straw bale home is significantly warmer than conventional building methods because a well packed bale is rated at r30 r35 minimum or considerably more. Zhang s next project is to construct an entire habitable building in dubbo in collaboration with john dash and the landowner. Post and beam or in fill and load bearing.

It was a hell of a task to pull it off especially since we loaded all the soil onto the surface of the roof one bucket at a time.