EcoNest Simulation: Sustainable Structures of Clay, Straw, & Timber

• EcoNest is a term coined by Paula Baker-LaPorte and Robert LaPorte to describe the sustainable structures they design using the theories of Bau-Biologie.

• Bau-biologie is the biology of building. Its concepts were conceived by Dr. Anton Schneider in Germany in the 1970s. Dr. Schneider’s building philosophy embraces many disciplines including architecture, biology, medicine, sacred geometry, and psychology. Together they form twenty-five principles for creating healthy environments.

• The Bau-biologie principles which contribute to a sense of well-being in this structure:

incorporation of natural light

architectural order of space

acoustical protection from noise

• embodied energy

» the use of energy efficient materials and building systems

» the avoidance of materials whose production exploits the environment

Assembly InputsBau-biologie principles which addressenvironmental issues globally are:• the use of natural and local materials that

are renewable and low in embodied energy

• the use of energy efficient materials and building systems

• the avoidance of materials whose production exploits the environment

II. Assembly Inputs1. Foundations & Footings• A 1,296 sq. ft. concrete slab was used as

the foundation. This is based on the 36’ x 36’ square configuration of the structure.

2. Columns & Beams

A softwood column/LVL beam seemed to be the closest approximation of timber frame construction. It also had the lowest energy consumption, least global warming impact, and lowest acidification, respiratory effects, eutrophication and smog potential. It was assumed that each timber beam would be 1’ x 1’ x 14’ and that 42 beams were needed for the timber frame, equaling 588 sq. ft.

3. Intermediate Floors• Wood joist with plywood

decking was chosen as the closest approximation to an EcoNest and, it has the second to lowest global warming effect. Using locally harvested wood planks such as spruce planks rather than plywood for the ceiling would likely reduce the environmental impact further. The ceilings in this structure are not vaulted to simplify and reduce further use of wood. Therefore, the same sq. footage was used as in the slab calculation.

4. Exterior Walls• Stucco cladding with concrete

block was selected as it seemed to be the closest to a straw/clay building. Square footage was calculated by using the following formula: 36’ length x 10’height x 4 walls less 25% for windows, coming to 1080 sq. ft.

5. Windows• 25% of the wall space was

allowed for windows to provide plenty of natural light and ventilation. Calculation: 1440 sq. ft. x 25% = 360 sq. ft. Wood was selected, assuming locally harvested wood would be used.

6. Interior Walls• The same calculation was

used for the interior walls as for the exterior walls because shoji screens would be used to delineate rooms rather than other building materials. Unpainted clay brick was chosen because it seemed to be closest to clay/straw building techniques.

7. Roof• A steel roof with pitched

wood truss and wood decking was selected because the EcoNest clients wanted a metal roof. Calculation was based on: 1300 sq. ft. x 2 with a 4’ “hat” or “solar bump-out” (300 sq. feet total) located on the home on the east to capture the morning sun and to assist with solar heating and also on the south side, providing a sheltered outdoor space.

Highest Impacts & Material Flow

WindowsHuman Health Respiratory

Global Warming

Acidification

Eutrophication

Intermediate FloorsOzone Depletion

Steel RoofPrimary EnergyWeighted Resource UseSmog

Summary: The windows and the roof show the highest environmental impact. And why not? The other building materials used in this project are local and natural clay, straw, and timber. But, we’ve got to have a roof and we’ve got to have windows! So, some metal and glass have been incorporated into the design.