Affordable green prefabs

When it comes to green building, some professions and industries get it, and some don't (yet).

Those who get it are architects and manufacturers. Those who are playing catch-up are suppliers and retailers, and most contractors and subcontractors.

So if you can get those who get it -- architects and manufacturers -- into one room, mix them up with an enlightened builder and entrepreneurial type, and ask them to create green homes, you can then train or hire the people to put them together.

That's the idea behind green prefab homes, built in a factory and delivered to your site. One company, Details, makes them in a former aerospace facility (which is using a green practice, to reuse existing space) in the Sacramento area.

Homes by Details are designed by architects and use green, healthy and energy- and resource- efficient products made by companies such as Kohler, Andersen and GE Monogram, as well as super insulation, tankless water heaters, and amazingly efficient HVAC systems.

According to vice president Bruce Evans, the total cost for one of these homes is from $115 to $215 per square foot, which includes site preparation, delivery and set-up. Some of the designs are pretty small, around 1,150 square feet (the Egret, shown here), which is again a green principle, to have a not-so-big house.

For more info, check out Details house designs.

Comments

[sheila]

too bad they don't have any modern designs!

this is probably a dumb question, but next time you are discussing modular/prefab/green building with your people, i'd love it if you asked this: can't you basically build on a modular basis on-site (as in using pre-established materials sizes as part of the design, like plywood being 4 X 8 feet) and create almost as much savings in wasted materials and labor as if you build it offsite and transported it?

i met with a builder recently and we were discussing the difference between adding dimensions of 24 X 20 X 8 feet and 25 X 20 X 10 feet. the labor and materials were almost double for the latter, because everything would have to be measured, cut, and built in a more wasteful, difficult way. plus, it put me at 500+ square feet, which meant an additional fee on my property taxes.

many things like appliances, water heaters, pex "home run" manifold plumbing system, blown-cellulose insulation, solar thermal and/or PVs etc. would be the same, i think, in-slab radiant water heating is always done on-site and if you just tidy up the concrete, you don't need an additional floor (which seems greener and cheaper than prefab, right?).

in other words, especially once you factor in transporting the structure, i wonder if there is much difference if you use the same principles of modular building on-site as opposed to in a factory? are there economies of scale that are truly significant?

thanks!

[Craig D. Rosenberg]

You could not duplicate the modular process on site. All of the work done in the plant is assisted by jigs and machines. In the plant, one man does the work of six men in the field. Overhed cranes move all heavy objects. A wall section that is 9 feet high and twenty feet long is moved into place with one man using an overgead crane for example.
The modular home plant buys materials in quantities for hundreds of homes. If you try to purchase on an individual basis materials can cost 30 percent more.
Just the setup for each step can cost more in the field than the entire job cost in the plant. For example, for spray foam nsulation, the contractor needs to set up a generator, a compressor, the hoses and spray nozzle as well as deliver the 50 gollon drums of foam. In the plant, this set up is permanent. The job itself takes only minutes.
The ecomimies of scale truley are that significant.
Also, if you build in the field and it rains, everthing gets wet and dirty. Modular homes built in the plant are imaculate and dry. Which would you rather have?

[Inland Empire]

As for "modern" designs, I am pretty sure they can change the exteriors. (I am assuming the idea of "modern" is something like mid century or minimalist). This type of house is popular in other areas because of not only the green aspects but the costs and quality.
After looking at floor plans for all types of homes for the last few years, I actually found my dream floor plan on the site. I will be looking into purchasing one in the next year.