Progress on the MicroHouse

Open Source Ecology’s two-module MicroHouse

MicroHouse Construction Manager Chris Reinhart is moving forward on the OSE Microhouse design. The Microhouse is a modular, low-cost, simple-but-comfortable, Compressed Earth Brick (CEB) house design. It is designed such that the different parts of the house can be build in parallel – walls, utility modules, roof sections, windows and doors, and others. We are approaching this design from a “Housing Construction Set” approach – where we are developing basic, interoperable, scalable, modifiable building modules. We are experimenting with the limits of earth housing as a building method comparable in cost and build time to standard stick-frame construction – while allowing for much longer building lifetime.

A two-module design has emerged, featuring a courtyard in between. One 12′ x 12′ unit will be devoted to work and sleeping space (possibly a sleeping loft), while the other will house a kitchen, bath, and dining space.

The Microhouse’s passive solar design for direct solar gain can be built using compressed earth bricks produced by our CEB Press.  The building collects heat from its southern exposure without losing it on the other three sides.

Design for direct solar gain—See Chris Reinhart’s blog, linked below, for larger image.

The bricks will be configured to create thick, insulating walls which will keep the MicroHouse cool in summer and will keep heat from escaping in winter:

Possible brick stacking patterns for MicroHouse walls

A reverse shed roof will allow for easy mounting of solar panels, and high windows are an option to vent warm air out of the building. In an innovative departure from conventional construction techniques, a modular roof design is being considered, with each module weighing no more than 200 lbs., so that a small team of builders can lift a module into position without the help of a crane. Compressed straw packed into each module serves as insulation. Chris plans to test and refine the roof module design concept before the actual build, as there is little information be be found on such modular roof design.

Proposed MicroHouse modular roof design

For evolving design details and planning, follow Chris Reinhart’s working design log here. Here at Factor e Farm, the Microhouse build, scheduled for September 28, will likely involve 24-28 people working in crews on various aspects of the building process so that build time can be minimized. The OSE team will be making continuing improvement to the CEB Press + Tractor + Pulverizer + Power Cubes to make it all happen.


  1. Nick Allen

    I’m excited about the microhouse design! I’m just up the road in Oklahoma and would love to get my hands dirty when the construction starts.

  2. Mark


    How are you going to make sure the straw insulation (great idea in itself!) does not get damp? And how are you going to eliminate fire hazards?

    You might want to have a look at the fascinating straw bale work by Barbara Jones and Tom Rijven.

    Might I even be so audacious to suggest using straw as the main building block? That might simplify things a lot, so much that one might be able to concentrate on building tools.

    A few tools that would make straw bale building so much more efficent: a stucco sprayer, a bale needle, a hygrometer, a heavy wooden hammer…
    The CEB press earth sifter could probably be used for this too.

    Kind regards,


  3. Tim

    What considerations for safety have been taken into account? For example, will that flat roof take the weight of a heavy snowfall?

  4. Audrey

    Hi Nick,
    I’m the Technical Community Manager at OSE. If you are interested in volunteering for a Work Day to help with the Microhouse build, please contact me at

    Hi Mark,
    Our design and construction material for this Microhouse is firmed up at this point. But we are always looking for other ideas. Please consider completing the Tech Team Culturing Survey on the wiki to get added to our list of technical collaborators for future projects.

  5. Anonymous

    […] we are developing basic, interoperable, scalable, modifiable building modules. Microhouse.jpg Progress on the MicroHouse | Factor e Farm Blog – Update: During the last few days of September and the first week of October we will be […]

  6. Chris Reinhart


    Email me at and I will get you more details and also get you in touch with the volunteer coordinator at OSE if she hasn’t contacted you already.

    Thanks for offering your help!

  7. Michael Evertsen


    I’m a grad student here at BSU, and I have been given your name by Walter Grondzik and Janice Shimizu. I am currently in the process of investigating rammed earth, and I my interest has been peaked by the work that you are doing. Can we catch up? Do you have time to Skype and allow me to ask some questions? I don’t know what your time is like, but any guidance or direction would be greatly appreciated.

  8. Ray

    Very interesting work!
    I’m not sure if I overlooked a feature here. Is the shed-roof designed for water collecting as well? If not, it might be another idea to add. That water could be sent into large drums or an underfloor cistern, treated and used for most purposes, or left untreated and used for toilets, general cleaning, and watering a small kitchen/spice garden.