Berea College Ecovillage - Sens House

Berea, Kentucky

The Sustainable Living Demonstration House, a residence for four Berea College Students from the Sustainability and Environmental Studies Department (SENS), serves as a laboratory for testing ways of living more sustainably. The SENS House is largely self-reliant for energy, water and waste treatment, employing a wide range of technologies for energy conservation and production, water conservation, waste treatment and use of local materials in construction.

The SENS House also serves as a gateway to the public visiting the Ecovillage. Arriving at either a drop-off zone along Jefferson Street or the Child Development Lab (CDL) parking areas, visitors may be greeted at a small "solar plaza" to the north before heading south through an entryway created by the SENS House, the Living Machine and the SENS Seminar Room. This covered entryway has display walls with interpretive information about the activities of the Ecovillage and an introduction to the Living Machine. The SENS Seminar Room forms one edge of an outdoor patio facing the Ecovillage Green, where visitors would pass through on their way to the CDL Community Rooms or the rest of the Ecovillage.

A timber frame serves as the primary structure for the SENS House, allowing flexibility in the choice of envelope materials, which may include straw bale, structural insulated panels, cob, and adobe or rammed earth. It is envisioned that students and community members could construct the SENS Seminar Room during a series of workshops on alternative construction techniques.

Inside, the SENS house is finished in materials selected for their environmental attributes such as coming from local manufacturers, having significant recycled content and recycle-ability at the ends of their useful lives, durability, non off-gassing, and low embodied energy. Low-flow fixtures and composting toilets significantly reduce the volume of wastewater, which is then treated on-site. This building is passively solar heated using wood stove as a back-up heat source. Hot water comes from active solar collectors and electricity is generated on-site using photovoltaic panels (PV).

The residents of the SENS House will develop and implement educational programs in sustainable living and technology for the College and the broader community, and will monitor and recommend strategies to improve the sustainability of the Ecovillage and the campus.


  1. RAINWATER FOR ALL DOMESTIC USE: will not rely on the municipal water supply. All water through rain capture and cistern storage; filtering as needed (water supplied by city as back-up).
  2. GREYWATER system, designed by Clivus Multrum, to treat all domestic water usage in an attached greenhouse.
  3. COMPOST TOILET: Human waste processed in the house with a no-water composting toilet. (ultra low-flow toilet, treated with the adjacent living machine, provided as a back-up.)
  4. BUILDING-INTEGRATED PHOTOVOLTAICS: produce grid-intertied electricity with PV panels equivalent to 100% of house use. A real-time monitoring of the electrical power produced will be featured on the SENS website.
  5. SOLAR HOT WATER: Water heating maximized by the sun (instant-fired propane gas heating as back-up). Each student will be issued a portable 5 gal. solar shower to place on a "solar rack".
  6. PASSIVE SOLAR DESIGN: building design, natural ventilation, super insulation, "sun-tube" skylights. No mechanical heating or cooling system. A "high-mass" wood stove is the only active heat source in the "kitchen/living wing", individual small propane gas heaters are used as supplemental heat in the "bedroom wing". The students (who share a tank with another housemate) will be responsible for providing their own propane.
  7. RECYCLING AND COMPOSTING: Make as easy and efficient as possible with built-in bins and storage space. The SENS students are in charge of composting for the entire Ecovillage.
  8. Maximize use of local, natural, non-toxic and low-embodied energy materials.
  9. During construction, maximize involvement of students, other college members, and members of the local community.
  10. Serve as the residence for up to six SENS students and as a center for education and demonstration in sustainable living and ecological design.

Proposal for Implementation:

The ecological goals of the SENS committee also extend to the construction process of the building. It is the desire of the committee that during the construction of the building, a few selected workshops be held to demonstrate first-hand appropriate building technologies. The proposed workshops are:

  1. strawbale construction – participants learn the principles of straw construction and stack the bales (sourced from Berea College) that are used for this project.
  2. cob construction - participants learn the principles of cob construction and build part of the structure. The SENS seminar space has been identified for this type of construction.
  3. wood timber frame – participants help raise the frame. The timber framers would cut the joints on the Berea campus.
  4. earth plasters – participants learn the basics of earthen plasters and finishes and would help in the application of these materials to the walls of the building.
  5. straw/clay construction - participants learn the basics of straw-clay (light-adobe), earth block and lift construction and finishes and help in the building of the south walls of the main house and the outdoor display area with this technique.
  6. landscape based workshops such as organic and bio-dynamic gardening, permaculture, etc. would occur after the building is completed.

Appropriate Technology:

Low Tech:

  • waterless toilet
  • straw and earth construction techniques
  • passive solar
  • greywater systems for the treatment of sink, shower and washing machine drain water.

Intermediate Tech:

  • high-efficiency fridge / freezer
  • high-efficiency washer
  • high-mass wood burning heater (possible second oven)
  • "sun-tube" skylights
  • Structural Insulated Panel /high insulation roof assembly

High Tech:

  • photovoltaics
  • high-performance windows
  • solar thermal hot water heater (with instant-fired gas backup)

Planning Issues:

  • inviting place to live
  • autonomy (grid independent) and self-sufficiency
  • solar access
  • building-to-land integration
  • demonstration building for larger community

Solar Systems:

  • passive solar space heating
  • active solar hot water collector
  • photovoltaics, to supply the majority of the electrical needs
  • solar ovens & cookers
  • thermal mass heat in the winter
  • passive hot air collector (greenhouse)

Energy Conservation:

  • air-tight construction
  • under-slab insulation
  • high-performance windows
  • high insulation
  • insulating curtains & shades
  • thermal mass
  • greenhouse can act as thermal heater for house

Water Conservation:

  • rainwater catchment, storage and use for domestic supply
  • greywater treatment of domestic water; used to grow plants in the greenhouse
  • faucet aerators
  • ultra low-flush & waterless toilet
  • ultra low-flow showerheads

"We hope the SENS House will demonstrate linkages to the local present and regional past and that it will do so in a way that aesthetically beautiful, unconventional and ecologically thoughtful."

~ Berea Environmental Studies students