I want to build a house: 1,500 sq.ft., passive solar features, $100,000 - possible?

March 7, 2008 9:16 AM

I want to build a house: 1,500 sq.ft., passive solar/energy efficient features, $100,000 - possible?

Barring the cost of the land. I'd like to be able to do this *realistically* - meaning, local contractors and nothing that would require building in the middle of nowhere to get a permit...

posted by raikkohamilonso to Home & Garden (25 answers total)

I think I've seen that ballpark for rammed-earth tire and bale passive solar designs. Probably depends in part where you're building it, both in terms of latitude and southern exposure. Permitting's going to be down to the locality, though. Certainly there are lots of places in the US with pretty restrictive notions of what a house should look like, which can seriously constrain your design options.
posted by mumkin at 9:20 AM on March 7, 2008

It's possible, but extremely unlikely. Residential construction would generally cost $100/square foot, and that figures a couple years old, but that would put your construction cost at $150K. Some energy efficient features won't cost so much--passive solar just means careful placement of your windows, with maybe some thermal mass--but just regular construction will probably break your budget.
posted by LionIndex at 9:23 AM on March 7, 2008

Maybe. A bunch of the passive design features are very low cost if you do it yourself, but permitting restrictions and the like may make it hard for you to incorporate them (eg: are you even allowed strawbale walls? What sort of building features are mandatory in your area?)

...you definitely want to nail down everything related to permitting and local codes ahead of time. With this budget you cannot afford to be surprised by a recalcitrant inspector, or find out that you are required to have some ridiculous building features. Lots of places have weird requirements that are secretly intended to keep low-cost homes out; the whole point of them is to add cost to the building.
posted by aramaic at 9:34 AM on March 7, 2008

Probably depends in part where you're building it, both in terms of latitude and southern exposure.

Make that definitely. Where geographically and environmentally (city/rural/etc).
posted by danOstuporStar at 9:35 AM on March 7, 2008

I reckon it'd be real helpful if you were to clarify what kind of passive solar home you're wanting to build, too, if you've decided. Are you thinking about traditional stick-construction with a big-ass bank of southern-facing windows? Poured concrete? Something quite a bit freakier, like an earthship?
posted by mumkin at 9:40 AM on March 7, 2008

I don't know the gritty details, but Auburn University's School of Architecture Rural Studio program is doing innovative things with recycled materials and alternative construction methods to build energy efficient low-cost homes in rural areas.
posted by BitterOldPunk at 9:45 AM on March 7, 2008

BitterOldPunk, things like what the Rural Studio does would be great to do, but I think that whatever you save in material costs by using alternative methods of construction would more than be eaten up by having specialty contractors or by paying to fix the mistakes of contractors that are unfamiliar with those techniques. The Rural Studio's secret weapon is that it's contractors are the students designing the things.
posted by LionIndex at 9:59 AM on March 7, 2008

I just built a house and it came out at $200 p.s.f. You're talking about $70 p.s.f. It is possible to build at that price, since that is pretty much what tract home developers' actual cost is, but the compromises you have to make are enormous. For example, shitty insulation, the cheapest possible heating (baseboards or gas-fired air), bulk-poured basements and so on.

Based on my own experiences I reckon I could build a decent, but basic, house for around $100-120 p.s.f. Anything less than that, especially if you are using unconventional construction methods, and I would be scared.
posted by unSane at 10:10 AM on March 7, 2008

You might want to check out these guys: http://enertia.com/

Price list for a kit here: http://enertia.com/Prices/CurrentPriceList/tabid/114/Default.aspx
posted by moitz at 10:11 AM on March 7, 2008 [1 favorite]

based on my limited personal experience it seems unlikely to me. my brother is planning on building a house similar to what you have described. last time i spoke with him he figured it was going to cost him $150,000 - $200,000. realistically he thinks it is going to be closer to the $200,000 end of the spectrum because things always go wrong.

he will be doing most of the construction himself.

my understanding is that prices can vary tremendously depending on your location though. he will be building in massachusetts.
posted by phil at 10:14 AM on March 7, 2008

Check your area, would be it economically feasible to buy a $1500 sqft warehouse and add "passive solar features" to it for $100,000? I think that would give you a very basic house with what you want. Would you want to live in it? Probably not.
posted by blue_beetle at 10:21 AM on March 7, 2008

You should really check out the blog 100Khouse. It is by a developer trying to build a home in Philadelphia for $100,000 (which he will resell) and that is exclusive of the land I believe. But this blog has lots of information about his costs, and the decisions that he is making to keep the costs down. I believe his home is only going to be about 1100 square feet, so I think your goal would be very difficult to achieve.
posted by bove at 10:34 AM on March 7, 2008

I don't know about permits--it probably depends on where you are--but cob houses are neat, and supposedly inexpensive to build. Might be worth researching some.
posted by hought20 at 11:09 AM on March 7, 2008

Just a data point:

About 3 years ago, I spent about $100k on a 900 sq ft addition in the Washington DC area made from SIPs. I was my own general contractor, but didn't do much labor myself. No passive solar, but top-of-line windows/doors and a solar hot water system...so maybe not really at all what you're looking for (esp if your building in an area where alternative materials are a good option), but maybe this will help you think of costs you've overlooked. The basic cost breakdown:

25k - SIPs manufacture/install (plus some very basic interior wall framing)
20k - Heating/AC (baseboard radiators, using existing gas furnace. New AC unit.)
15k - Asphalt roofing and vinyl siding (cheap, environmentally evil)
8k - Windows doors (7 largish windows, 2 french doors)
7k - Solar hot water system
5k - Floor decking and joists, beams
5k - Bamboo flooring
15k - Everything else (drywall/paint/trim/etc)

I spent another 12k or so on architect fees. There's a lot of stuff that goes into a house.
posted by danOstuporStar at 11:33 AM on March 7, 2008

Just a data point: Here in St. Louis, EcoUrban, a new local green home company, built an 1,875-square-foot, LEED for Homes Platinum–certified display home for $275,000. That was starting with a base model that would've been $219,000 and adding about $50,000 in upgrades, and not counting the cost of the land. They crammed a lot of amenities into that, and the home's gorgeous.

Now, they're able to do this by building pieces of the home in a factory in advance, then putting them together on-site. That probably cuts costs a lot. But if you found a similar green home builder in your area, they might be able to work something out.

You could also buy a couple of Rocio Romero's LV150 modular home kits and add 'em together.

I think what you want to do is definitely possible—you just have to find the right combination of ingredients!
posted by limeonaire at 12:18 PM on March 7, 2008

If you are willing to do a lot of labour yourself and use the cheapest of everything (the cheapest flooring, the cheapest trim, the cheapest fixtures, the cheapest IKEA kitchen, etc.), you would have a chance of being able to do this, but it would be far from easy. It would also depend a lot on the costs in your area.

You might be able to afford straw-bale construction (straw, cement, and sand are cheap and your labour is cheap too), an on demand gas hot water heater, and an EPA certified wood stove or an efficient gas furnace, and cheap low-E windows (good glazing, cheap otherwise). I don't see how you could afford solar hot water or solar electricity, though you can build the house so that it is easy to add them later.
posted by ssg at 12:28 PM on March 7, 2008

Bah to the nahsayers!
Go for it, and remember, having a house built doesn't mean having the whole damn thing built.
Once the subfloor is in, do the flooring yourself. Once the walls are framed up, apply the tyvek barrier yourself. Do your own drywall and paint. Do your own cabinets, especially in the kitchen (metro shelving is cheap, sexy, durable and EASY). Roof it yourself (meaning, get five buddies to help). Insulate it yourself. Some of the stuff you can do can be put off and done later, as time and money allows - like trim and crown molding, installing the toilet and cabinets in a second bathroom, etc.

Sure, most contractors will frown on a lot of this stuff, but they're used to working with bozo customers and making good money for their trouble. So don't be a bozo. Think things through. And find a contractor that's excited about your project!
posted by terpia at 1:12 PM on March 7, 2008

No.

Build something smaller you can add on to.
posted by flummox at 1:43 PM on March 7, 2008

Look up prefab housing... I think that I just recently saw a prefab home builder doing environmentally friendly jobs for under 100k. You might have to give up your 1500 sqft dreams though.
posted by zhivota at 2:22 PM on March 7, 2008 [1 favorite]

Read this first, then this, then consider carefully whether you really do want all 1500 of those square feet.
posted by flabdablet at 3:25 PM on March 7, 2008

Check out the Copod. Don't know if you can get it in the states or not. But it becomes the center of your home. You can use solar panels and such.
posted by nimsey lou at 4:05 PM on March 7, 2008

Paying for labor and contractor mark up, I doubt it. However:

I long for a world where green doesn't equal big bucks in the minds of the people. Heck, it's part of my job to push that idea. First off, decide on your goals. Are you looking for "sustainable" or "Efficient" or "both." Right now, if you choose "both", you're going to be hard up. However, choosing one or the other and you might have some luck.

"Passive Solar" just means, generally, lots of southfacing windows with overhangs, strategically planted trees, and intelligent use of blinds and carefully selecting the windows you DO use. For more info, checkout southface.org, they are awesome.

For complete house plans that are AMAZING, check out the "national affordable housing network", at www.nahn.com.

Few non-niche contractors are currently going for green materials, however with the new LEED requirements for federal building, as well as with several states adding bonus points for LEED and Green Advantage certified builders, that will soon change.

My point is that you're not going to get a contractor to build you a cobb house, or a strawbale, or an earthship, or likely even rammed earth. You will have some success with SIP'S, AAC's (I <3>
I would, as I start to talk to contractors, call them and throw some terms at them. Tell them you don't want "Sticks and bricks", but you'd like to consider "ICF's or AAC's". Contact a local university, green advantage, or other green-certifying organization and see who's who in your community.

If you live in the country and can get out of bassackwards code enforcement of 25 years out-of-date codes, then you're set. Otherwise, it can be a nightmare.

Really though, check out all those links. Those NAHN houses are meant to be built fast and cheap, and they are amazingly efficient. It's also important to add that if you do a little extra planning, you can modularize all these systems and make your home bigger as you see fit.
posted by TomMelee at 7:03 PM on March 7, 2008 [1 favorite]

Don't forget that whatever you pay in better heating and air conditioning now, the higher the savings. I don't know your climate, but a decent heat pump in a warmer area will return more than its higher cost in savings after a short time. Same thing with good air-air heat exchangers which are becoming a necessity with tightly insulated homes. Consider geothermal heat/ac. Just like a heat pump, but it runs water down a coil drilled or buried into the earth to extract heat or spill heat.

My point is, as was the point of others, make sure the house is actually what you want it to be, and ignore the things you can easily change later. Maybe you deal with painted floors in exchange for more insulation. Trim is hard to upgrade after the fact, doorknobs are easy.

Most important is choosing the right piece of land and using it to your advantage. Make sure whatever your southern view is is something that can't easily change. You'd hate to spend the time and money designing and building a home and systems that account for the solar power, and then have an apartment building sprout up next door blocking the rays.

Also a good idea to use stone or concrete on the south facing wall as a natural heat absorber and retainer. And then insulate the bejesus out of the thing. I grew up in all brick homes that didn't have overhangs (or insulation) and the walls would just radiate heat all night during the summer. And my grandfather built a house into a hill where the south face of the house was three stories of glorious southern exposure, and the north face was one story. A really neat house.
posted by gjc at 7:49 PM on March 7, 2008

Response by poster: Thanks to all for the really great answers!

Let me elaborate:

I am in the southeast;

I believe the construction costs in my area are "quite low" relative to the rest of the nation;

I am really thinking along the lines of "what can be done to a relatively "traditional" construction house" - geothermal heatpump, south-facing alignment, passive internal mass, etc..?;

I'm thinking strawbale/etc. would be too difficult to arrange permits for - and to make happen in general, although I am not looking at lots in "overly restricted/covenant-laden" developments.

Thanks for all of the great replies -
posted by raikkohamilonso at 8:24 AM on March 8, 2008

Geothermal alone for a house that size is going to be in the $15k-$25k range. Geothermal is great (I put it in the house I built) but it's not a cheap option. You can downsize it by increasing your insulation, but again that costs $$.
posted by unSane at 6:06 AM on March 9, 2008