Fact Sheet on Straw Bale Greenhouse

Straw Bale Greenhouse Facts

We set forth with the idea to create a greenhouse that provides a healthy environment to grow plants, that doesn't need to burn up fossil fuels to heat it, and that preserves the rich agricultural heritage of barns, barns that are rapidly disappearing from America's countryside. -- John Ivanko

Location: Inn Serendipity Bed & Breakfast (and farmstead), Browntown, Wisconsin

Building: approximately 1,200 square feet (two stories)

Project Designers: John Ivanko and Lisa Kivirist, co-owners of Inn Serendipity, Matt Sterling, Native Earth Construction, and Phil and Judy Welty, formerly of Solar Use Now (S.U.N.) of Wisconsin.

Builder: Native Earth Construction (Matt Sterling)

A Community "Barn-raising": All summer long and well into the fall, 2001, during so-called "Straw Bale September," we were graced by the talents, enthusiasm, and support from many people both near and from afar. The MREA workshop participants were among the many (some pictured at right) who came to learn, share meals, and work with their hands on what perhaps Wendell Berry might call "good work."

Green Design:

Straw bale (organic infill) walls using existing timber framed structure. Straw bales provide an estimated R-43 insulated value and are employed in the full wall on the north side and in partial walls on the east, west and, minimally, south walls.

FSC-certified (Forest Stewardship Certified) aspen and black locust was used throughout in the building construction when new wood framing or trim was needed. Black locust served as substitute for Western Cedar, typically used in trim for weather-resistance and durability reasons (nearly all Western Cedar comes from old growth and endangered forests). All FSC wood came from the Sustainable Woods Cooperative. Minimal use was made of pine or plywood, most of which was recycled from within the barn deconstruction or from sources in the community.

No-VOC (Volatile Organic Compounds) caulks from Safe Building Solutions were used throughout the structure to improve air quality and minimize out-gassing.

Recycled and reused materials were the mainstay of the framing, doors and most of the windows. Misfit windows were added to the second floor on the east and west sides.

South-facing double-pane insulated glazing was purchased from Arctic Glass.

Solar Design: Direct solar gain from south-facing glazing and partial east and west glazing. Building oriented along east-west axis to optimize passive solar performance. Heat sinks consist of several water tanks.

Heating System:

Primary: An active, closed loop, solar hot water heating system utilizing ten 4'x10' Gulf solar collectors to allow the sun to heat a environmentally-safe antifreeze solution and, through two 1-1/12-HP Grundfros pumps, circulate the fluid into the greenhouse where the heat is exchanged with over 780-gallons of water for ease of storage. The heated water, an ideal storage of thermal heat (measured in Btus), is then pumped through a McQuay liquid-to-air exchanger to heat the greenhouse.

Secondary: Reusing a salvaged No. 2 fuel oil furnace, we burn B100 (100-percent biodiesel) to heat the building when we have a series of cloudy days. Our goal is to have a minimal heating expense for the greenhouse. We process our own biodiesel from waste fryer oil collected at area restaurants and in partnership with a nearby farmer, "Uncle Phil."

Tertiary: Passive solar heat is collected through Kal-Wall solar water tanks and a Phase Change salt tube on the second floor, each with properties to collect and store heat, releasing it slowly through the day/night.

Energy Systems: 680-watt photovoltaic (PV) System and Wind Turbine System help to meet the annual electicity needs of greenhouse (lighting, pumps, etc.). The greenhouse is connected to electrical service provided by Alliant Energy with a standard grid intertie. All electricity used at the Inn Serendipity farm is from 100-percent renewable energy, based on the Second Nature program offered by Alliant Energy. An experimental Savonius Rotor Vertical-Axis Wind Turbine is under construction to possibly power several DC pumps and supplement water tank heat in the winter (independent of the grid).

Lighting: Super-energy efficient enLux LED floodlights, in red and blue spectrum, for the second floor primary growing area, plus salvaged fluorescent lights (blue/green spectrum).

Water/Irrigation: Based on a rainwater encatchment system (in progress), irrigation will be gravity fed from external tank.

Ventilation: Due to the experimental design, on-going testing and monitoring will occur related to temperature and humidity. The north wall includes two intake vents and the doors and windows on the east and west side of the greenhouse can be opened as needed, improving air flow, air quality, and enhancing needed carbon dioxide for growing. Modeling a "forest ecosystem" by having both a "canopy" (second floor) and "understory" (first floor), efforts to manage different micro-growing climates will be undertaken.

Landscape:North side of building is protected by evergreen trees. No pesticides will be used for the gardens, orchards, or at the farm.

Roof System:Utilizing a metal roof material based on recycled metals, a new roof system and skylights were added in 2004. Funding support is being explored.

Site Integration: Integration of greenhouse into diversified small-scale organic farming operation and tied into bio-regional approach to family-farming.

Comprehensive Farmstead Overview and Self-guided Booklet: Print out the 20 page booklet, The Good Life Guide: A self-guided tour of Inn Serendipity & the renewable energy systems that make it possible for a more detailed overview of the renewable energy systems employed on the farm.

Demonstration Grant Funding Support: Portions of this website and related Good Life Guide: A self-guided tour of Inn Serendipity & the renewable energy systems that make it possible were made possible, in part, through funding provided by the Wisconsin Focus on Energy program.

Inn Serendipity
7843 County P
Browntown WI 53522
Tel: 608-329-7056
E-mail: info@innserendipity.com
Website: www.innserendipity.com