Straw Bale Portable

Straw Bale Portable 3 Photo by Chris Vander HoutWestwood Public School, Straw Bale Classroom Portable

Guelph, Ontario

Completed 2014

Floor Area: 816 sf  32’ x 24’ )

 soma earth acted as Project Architect


Straw Bale Portable 5 Photo by Chris Vander HoutThis unique pre-fab, straw bale, 800 SF portable classroom project was built for the Westwood Public School, Willow Road, Guelph (for the Upper Grand District School Board). Created by Ben Polley  & Chris Vander Hout of Evolve Builders, based in Guelph, this is a special building where it was pre-assembled off-site in 2 halves and then shipped by truck to the site and put in place, functioning after only a week or so of onsite building. The finished photograph here is of the Rockwood Elementary School Portable which was the original prototype.  This design is meant to be offered to school boards across Ontario as a healthy and sustainable alternative & greening initiative.  The in-construction photographs are of the Westwood Public School portable taken in November & December 2013.

” Building with bales limits many of the indoor air quality problems experienced with the old-style conventionally-built portable classrooms, and passive solar design and renewable energy features makes our “eco-portable classrooms” a much more sustainable option for the health of both our students and the planet.” – Ben Polley, Harvest Homes

Albeit this was designed as a classroom building, we think this is a great idea for creating a start-up building on a new piece of land for much less than the cost of beginning from scratch.  With an additional foundation and adding interior partitions, kitchen, washroom and a simple wood stove, you could likely start with a 1000 SF, 2 bedroom house, for about $150,000, give or take, depending on how resourceful and DIY you might be in creating the interiors & finishing touches yourself.  Over time, you could add a front porch or another addition, as your expenses could allow; keeping any initial mortgage amount owing, as low as possible.  These ideas are part of the Homesteading, Self-Sufficient Living ideas that I am constantly considering these days.  If this direction interests you, please let me know and we can discuss this together with Ben!

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Unique Sustainable Classroom Portable Features

  • Fire resistant, super-efficient, straw bale insulation
  • Glass viewing window into straw bale wall
  • Tightly sealed structural insulated panel (SIP) for both floor and roof structures
  • Fiberglass framed windows complete with invisible coatings on the glass to either retain or reject heat as specified plus special thermal spacers between the glass panes for further improved efficiency
  • Natural, vinyl-free, wax-free, anti-microbial linoleum floor tiles
  • Highly durable mineral based wall paints, in and out
  • LED light fixtures
  • Natural oil finish on exposed interior solid wood
  • Solid wood soffit
  • Long lasting, colourful steel roof formed from recycled material

Standard Features

  • 800 sq ft building footprint
  • High efficiency dusk to dawn exterior light
  • Electrical & communications enclosure
  • 125 KW electrical panel with mast for hook-up
  • 7 electrical outlets; 2 zones of switched lighting
  • 2 data boxes for on-site internet hook-up
  • 2 electric 1500W baseboard heaters
  • Complete, integrated fire alarm/sensor system
  • 14” deep, laminated window sills
  • Commercial grade, 36” insulated steel door
  • 4 slots in frame for duck bill type anchoring system
  • Fastening blocks for skirting attachment (by others)

Owner Selections

  • Roof and fascia colour combinations
  • Flooring and wall base colour
  • Window frame and entry door colour
  • Interior and exterior wall paint colour

Additional Options

  • Solar hot air collectors
  • Solar photovoltaic panels for electricity production
  • High-efficiency combination air exchanger/heater
  • Air conditioning coil integrated into air exchanger
  • Half-lite safety glass window on entry door
  • Custom floor tiles or architectural sheet linoleum
  • Custom colour-matched paint colours
  • Additional electrical or communications outlets

All photographs are by Chris Vander Hout of Evolve Builders.