2 - HTM interior design photos of our zero-energy open floorplan earth home

​HTM, sustainable, natural zero-energy passive solar housing in the 'earthship' earthome style. The basic design of our high thermal mass HTM™ sustainable housing, passive solar design is presented in the earth home style, but can be easily molded to fit your family's lifestyle and personal preferences, especially the exterior appearance. The open floorplans of our natural, sustainable, earthhome design can be boxed in later for storage, quiet areas, and sleeping spaces. Just keep in mind that as you section the home off, the need for supplemental heat and light is only going to increase. This is the basic nature of low-tech, mechanical-system-free passive solar architecture. Striking a balance between aesthetic desires and passive functionality is key with any truly sustainable design.

Indoor planterbeds get direct almost 90 degree penetration sunlight through angled glass at winter solstice. This ensures maximum solar heat gain and natural light when they are needed most right in the middle of a cold, dark winter. Sloped glazing may have an unconventional look about it, but it is the only way to sustainably grow crops AND heat a home. With a well-chosen building site, the glass can be hidden on the backside of the home in urban areas to mimic the look of a conventional house from the street. If you live in a hot climate, the need for sloped glass is likely not an issue and you can go with vertical glass to save money and present a more conventional look.
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Passive Solar textbooks all seem to present a rather confusing 'shotgun effect' with a laundry list of options, all based upon conventional residential stick-frame architectural models... but some do think outside the box:

  • Malcolm Wells' The Earth Sheltered House: an artist's sketchbook is rich in drawings and inspiration 
  • Robert L. Roy's Earthwood Series includes SBC construction details and curved wall structures 
  • Michael Reynold's Earthship Series for back-to-basics rammed earth how-to-do buildings 
  • Daniel D. Chiras' The Natural House and The Solar House are both excellent textbooks 
    and with more focus on HTM construction
  • our free Passive Solar Design eBook

We no longer provide any HTM passive solar home design consultation services.
Our design practice is closed to new clients while working on a new book and personal projects.
And unfortunately, architect and contractor referrals are not possible to for us to provide.
HTM Home Tour DVD is available, but it does not include any personal consultation time.

HTM Home Tour DVD


Not a do-it-yourself video, but rather a narrated HTM™ passive solar, earth home tour. Second half-hour features Infiltrator® chamber leach field septic system installation tips, plus some classic footage from Sun-Mar® composting toilets. All proceeds benefit LAPS, a local animal charity.

HTM Passive Solar eBook - Table of Contents

  1. Introduction to HTM design basics with the following pages going into detail
  2. photo gallery is packed with photos and commentary from our HTM Home Tour DVD video
  3. dry stack surface bonding cement construction photos and sample block layout sketches
  4. floor plans is an annotated progression of layout design choices for more functional HTMs
  5. roof detail chapter outlines T&G plank-style vented roof decking atop log purlin joist beams
  6. sun screens shade panel micro-climate passive cooling design tips and installation tricks
  7. heat storage with fiberglass water tanks providing a means to moderate temperature swings
  8. earth tubing is a simple, passive method for tempering a household's fresh air return intake
  9. solar orientation is important, but HTM designs excel in hot or cold climates alike... anywhere
  10. exterior fascia SBC stucco coatings over EPS foam board insulation and sloped glass details
  11. wing insulation details and shallow footer, frost-protected perimeter foundation treatments
  12. planter beds are central, functional features in greenhouse style HTM home construction
  13. links page is packed full of handy research references and relevant manufacturer websites