We can't get you one right way in Washington but we are hoping to be able to supply energy efficient prefab houses to the West Coast in US and Canada in the near future. If you fill out the 'request a quote' form that can be found on each different model you can get more info on particular house designs, and we will be able to send you an email when there are some available in your region. How soon are you building?
Where do I start to build a small, affordable, low-maintenance house?
What we can do is give you a list of things to consider and things you will need to decide on. This is at least a starting place, feel free to ask follow up questions about any of it, here goes!
A ‘Tiny House’ is typically on wheels, but in our opinion, immoveable homes are better. If you are looking for a mobile tiny house, here are a few links to check out:
If you are looking for a stationary house, you need a piece of land to build on. I’m not sure, but do you have that land already? Great if so, but before purchasing a building lot I would check with the local municipality if they have a minimum home size requirement, and if that is a size you are comfortable with. Here are some pages to help.
Choosing between a slab on grade and basement – slabs are cheaper, more ‘eco-friendly, healthier and more durable. You can buy a prefab slab kit, or you can have one designed by an engineer and build it yourself (with your army of helpers) Keep in mind, depending on site conditions an soft costs such as engineering and permitting, one isn’t always cheaper than the other between prefab and hand made, so price them out.
We will have more news in the near future about innovative prefab kit homes that are LEED Certified and Passive House ‘ready’, in that they are of a quality that can meet those requirements. That’s a good thing for living off grid because it keeps your heating costs down, which In your case I imagine is likely firewood? Some solar heating options are linked below.
This is probably waaaayyy more info that you were expecting, and some you may have read before but I just wanted to make sure you found a few of our more obscure and interesting off grid articles. You can find all that stuff and more in the Ecohome Building Guide Pages, but also pop in any keyword like 'off grid' in the search box at the top of every page and you will find even more. Good luck!
What are the most cost-effective green building strategies in new home construction?
There are for sure a lot of green home building technologies and products out that will eat up your money rather than help you save it, but for the most part a more energy efficient, durable home will save money, and it will do so fairly quickly.
And to address the rest of your questions, I think that's an awesome list so I’m copying and pasting to go through it point by point, and I’ll add thoughts and comments and pertinent links, though some you may have already read.
Calculating the amount of glazing (not too much, not too little) – Windows facing North, East and West will always lose more heat than they gain on a daily and seasonal cycle, so be sparing with them, and see our pages on choosing the best windows for high performance homes, and remember that it’s best to have different low E coatings on the south than other sides.
Having glazing facing the right direction (e.g., south) See our page on passive solar home design, but the short story is - south facing windows can gain more heat than they lose.
Tight air-sealing of the envelope – Absolutely, make a home as well-sealed as you can and let your ventilation equipment do their job. A poor air barrier and lots of air leakage can account for 1/3 of heat loss in a home.
Geothermal heating/cooling – We love it as a concept and its great for larger buildings not smaller homes. Your money would be better spent on insulation, quality windows and all the stuff mentioned above. Geothermal will ‘cut your bills in half’ for maybe 25-40K, so if your heating bill is only 3 or 4 hundred bucks a year then you’d need to live longer than Yoda to make it worthwhile. Read here to see if geothermal is worth it for homes