This little sleeping cabin was the first shed roof design cabin built at Blue Rock Station.

Straw bale cabin with living roof.
Firefly sleeping cabin with living roof

It was originally designed as a screened in sleeping cabin that could be used in the summer months. In the last year or so we have converted it into a potting shed to service our forest garden project.

The building sits upon a rammed earth tire foundation, with straw bale walls, a living roof and a slate roof on the porch.

We experimented with the living roof on this project – and found a new method that works quite nicely. Most living roofs incorporate a waterproof membrane (6 mil plastic, for example), then a bed of gravel for drainage, then landscaping cloth (to keep earth from gumming up the gravel), then earth and plants.

The weight of this system is considerable, plus the gravel and landscaping cloth must normally be purchased. Also the gravel tends to drain too quickly, leaving the plants dry.

We tried it with the waterproof membrane, then a layer of biscuits of straw. On top of the straw we put earth and plants (no gravel or membrane). Seems to work a treat. The plants stay moist, the water still drains, and it is much lighter and cheaper.