A jumbo straw bale guesthouse in Italy.

The guesthouse was designed by architect Werner Schmidt who builds many homes from big bales 1.2 m (4ft) thick. Such big bales mean the house is extremely well insulated. The building is very energy efficient with clay plasters and floors that act as a thermal battery storing energy from the sun during the day and releasing the energy during the night. In winter there are a few months when the sun rarely appears so a central wood heating stove keeps the building warm. In addition there is a fireplace in each apartment. Other than during the low sun period in the winter the building requires no additional energy.

The guesthouse is divided in to two apartments (see floor plan right) and the rooftop studio with its glass roof. Each apartment of 84m² (900ft²) living area has two double bedrooms, private bathrooms, separate toilets and a large open plan living room with kitchenette and fireplace. Visitors to the guesthouse say they sleep well surrounded by the natural materials that make up the interior and structure of the building where there is nothing cold, sharp or hard.
 

The building is load bearing, that's where the roof rests on the big bales (240cm x 120cm x 70cm) without a timber frame structure to support it. The roof has a 45 degree slope to shed the large winter snow loads, protected by larch shingles (see below left) above its big bale insulation (see above left). Under the glass roof top is a studio space with access via an external covered stairway.

Clay plasters and floor act as a heat battery