Thanks for your help.

Greg Cozzi

I could live in a place like that. I actually kinda want one.

A few concerns – some already mentioned:

Termites – might they not have a field day with an improperly detailed pole house as well? Seems that any wood, near the ground, improperly detailed and protected, will be a target for water damage, termites, and other degenerative issues.

A cold climate version of this house would need to deal with insulation – as the exposed underbelly of any construction would be a weak link in a winter clime with wind and temperature swings. The ground, at some level, starts equalizing temperatures – so why not cozy up and take advantage?

SIPS – not really buying it that they are a sustainable source for home construction. The tie in to chemical companies (more dramatic if using a urethane based panel), offsite – highly technical manufactur of those panels, shipping of the panels, and the eventual inability to seperate components for recycling or downcycling (should we need to take apart a SIPs structure in 50 years) – are points against the system in my opinion. Efficient – yes – but you will also need to add an air changer to the mix – as most SIPs homes are of very tight construction – and indoor air quality (rember all that OSB and foam that is surrounding you?) will off gas, as well as keep moisture and interior finishes all locked up in the house. Small, solar powered fans may do the job… but its one more reliance on yet another system to add to the mix. Adding more complicated systems in to then change air, regulate temperature, adjust humidity… etc. don’t really seem to fit into a simple, direct, sustainable dwelling.

Perhaps a pole structure and a straw clay, straw bale, lightly framed wall with recycled cellulose or other bioregionally suitable enclosure system would be better…

Pre-manufacturing also takes away from the local economy – something that I feel is very important for sustainability to become “real”. I like (and work) for several timber frame outfits that manufacture and ship all over different regions of the country – and I think that shipping pre-made components can sometimes be beneficial – but in my gut it seems that a local craftsman, using local materials, hiring local labor, would better serve the long view of the client and the planet. (I say this cringing, as the complicated world we live in affords me creative work, while conflicting with ideas I feel would better serve a just, sustainable world!)

Proper engineering of any structure should help in hurricanes, earthquakes, and the like. Part of the beauty of a post and beam system (or timber frame, or steel frame) is that at some point in the future varying systems of the house can be stripped away, recycled, and possibly reused. A stick built home will probably go into the shredder – as fast growing wood, full of nails will likely be difficult to reuse. Keeping the materials simple and honest, for as long as possible into the lifecycle, affords great flexibility of design – 50, 100, or 200 years from now. Large beams can be re-used, and if not – they often can be made into smaller members – either for timber, or for flooring, furniture, framing, or other millwork.

I agree with Tim’s comment about natural venting – but I would extend that to ANY properly designed structure. There is no magic bullet – we need to study the land where we live – and build withing the logic of that landscape. Pole houses make sense in certain climes, when designed properly to meet the needs of the site, weather, occupant usage, and hopefully the future. I feel strongly that most of our housing woes could be fixed by simply paying attention to our local environment and evnironments of regions similar to our own – and adapting our construction techniques, details, and lifestyles to suit those parameters.

Nice work! And good discussion!

In arid, warm, or tropical climates, thermal massing is not a major concern, as you state. Promoting proper air circulation underneath, over and through the home is essential in mitigating the damaging effects of heat, humidity, mold and mildew. A properly designed and vented pole house will not require an HVAC system for cooling comfortably. Insect infestations (especially the voracious Formosan termites) are easily controllable with a pole house.

Conversely, conventional stick-built slab on grade houses in warm or tropical regions are not inherently eco-friendly, nor energy efficient. A slab on grade house will usually require expensive energy consuming HVAC systems (which are prone to support molds and mildew in warm, humid and tropical climates). Sitework disturbances are also expensive and the natural surface water run-off patterns are interrupted with slab on grade construction. Termites and other damaging insects can have a field day with a slab on grade house. A pole house sits gently on the land requiring virtually little natural site disturbances.

As for a pole house in an extreme winter climate, we recommend the use of SIPS (or other rigid foam insert panels) for floors, walls and roofs. Passive solar systems are still viable solutions with a pole house. A pole house can also be built over an existing or new basement, utilizing the cost savings inherent in the engineered structural pole house system. The exterior non-load bearing walls of a pole house can even be placed over low concrete stem walls, creating a traditional crawl space beneath the home.

In AE and VE Flood Zones, as well as the High Wind Hurricane Zones, a properly designed and engineered pole house will perform far superior to any conventional stick-built slab on grade house, or an elevated post and pier stick-built house, at a comparable per SF cost factor. We design our pole houses to meet and exceed the current IBC (International Building Codes) for high wind hurricane zone uplift loads, AE / VE flood zones, as well as seismic resistance requirements.

Thank you,
Tim Cornell
Managing Director
Polehouses.com

Thanks for writing

Sarah

prefab homes are obviously more sustainable than a typical trailer and the average development house, but i don’t think you could say they are more sustainable than a site-built home which was built with sustainability and the health of the immediate surroundings in mind.