An Unconventional Approach to Building My Own House
I’d like to get a “minimum $180/sq ft” price estimate from a local builder down to $50/sq ft by being an owner/builder in partnership (more like apprenticeship) with a builder because my loan requires a licensed, bonded and insured builder to be involved and I’m coming into this with only book knowledge. I’d like to build my house from mostly onsite materials (general assumptions as site is to be determined); 1 foot thick cob (natural “concrete” of clay sand and straw) walls, with 2 feet thick of light straw clay exterior insulation, reinforced by bamboo if needed. I’m considering a rubble trench foundation, but the roof and foundation are still largely undecided. With design, I’d like to achieve enough insulation and passive heating/cooling to keep the house between 65-75 degrees year round with the smallest possible heat pump for back up in Hood River, OR. I’m planning a single story rectangle in form, East-West oriented with a full south glazing. 2000 sq ft, 4/5 bedrooms, 2/3 baths, office, open kitchen/great room etc.
Some questions:
Where do I find a mentor/builder? Any takers? Or good references?
Any pointers on my initial design ideas?
Do my initial build/material ideas seem reasonable/doable/reliable etc?
Any general suggestions on foundation and roof? (The more on site materials the better)
Any advice that helps achieve $50/sq ft?
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A quick search on Google for "natural builders in Oregon" will give you several folks to call. That's a niche construction that few of us have knowledge and/or are experienced at.
> Do my initial build/material ideas seem reasonable/doable/reliable etc?
No. Seems like you want to do this yourself (otherwise how would this go from $180 -> $50 sq. ft.?), and with those materials it's likely to take forever to build a 2,000 sq. ft. house.
> Any advice that helps achieve $50/sq ft?
A time machine.
> I’d like to get a “minimum $180/sq ft” price estimate from a local builder down to $50/sq ft by being an owner/builder in partnership (more like apprenticeship) with a builder because my loan requires a licensed, bonded and insured builder to be involved and I’m coming into this with only book knowledge.
In this theorized relationship, the builder is taking on all the risk (and more of it). I would expect them to charge you a risk premium for doing so (if you could even find such a builder). I'd also be surprised if a bank would even approve such a design given how non-traditional it is for 2021. Also, DIY building pretty much rules out construction loans because construction loans are time-bound. Any bank is unlikely to have a loan duration long enough to account for this sort of project. If they do, the rate is likely to be quite high.
Armondo, thank you for the advice. I have already been down that route and am still going down that route. I’m trying to cast as wide of a net as I can.
I do not need any advice on how to handle my loan. This is already approved by my loan. My loan is for low income, with interest rate subsidies down to 1%, zero out of pocket expenses, and extended loan terms up to 38 years. It is a non profit loan program. They want me to be a part of the build process.
I do not need advice on building codes. There are already permitted homes in my area built from these materials.
Patrick, I do not need advice on timeline. Similar builds have been completed in much less time than I have. I would like constructive advice instead of a “time machine.” In an apprenticeship, the mentor does take on the risks, and apprentices do not get charged premiums. I am looking for an apprentice - mentor relationship. Constructive advice in regards to this would be appreciated.
Dc contrarian, I am cheap! You could also call it leveraging funds as much as possible. This is why I want to find an apprentice - mentor partnership.
Malcolm, the builders estimate is not based on an apprentice - mentor partnership. $50/sq ft is based on owner/builder figures with these materials of $5-$40/ sq ft and the national average being $129/sq ft. Constructive advice on how to get anywhere between $50-$100/sq ft within an apprentice - builder relationship would be appreciated and maybe more willing to be answered.
Martin, I plan to keep things on the simpler side. Any constructive advice and cost estimates within an apprentice - mentor relationship would be appreciated.
I’m surprised there isn’t much advice on these materials as this site is called “Green Building Advisor.” These are some of the greenest materials you can use. Beautiful, permitted homes are built from cob.
Insulatedcobber,
If you don't need the advice of the experienced builders and editors on GBA, I'm at a loss for why you posted your question. Unfortunately the replies you received aren't what you wanted to hear, but looking for someone to simply confirm your biases is a dangerous way to start any project.
Malcolm, I’m receiving unconstructive advice unrelated to my questions. Constructive comments are appreciated. I am looking for an apprentice - mentor builder relationship.
Insulated,
Lots of people in your position improve their skills by enrolling in courses at Yestermorrow School in Vermont.
Rest assured, Yestermorrow is cob-wall-friendly.
Insulatedcobber,
Good luck with your project. Martin's suggestion is a good one. Yestermorrow would be exactly the right type of community to find what you are looking for.
> In an apprenticeship, the mentor does take on the risks, and apprentices do not get charged premiums.
Yes, apprentices do "get charged". Apprentices work for below market rates. Why is this? Because they're effectively paying to learn.
Wouldn’t this be what I’m looking for then? I’m willing to work for below market rate ($0) and I’m willing to pay to learn (up to potentially $300,000).
Not meaning to make light of the situation, but there is a builders joke that goes:
My rate is $60 an hour.
$70 if you watch.
$80 if you want to help.
Let's do some math. You're talking about going from $180/sq. ft. to $50/sq. ft. for a 2,000 sq. ft. house, a savings of $260,000.
Let's put aside things like per sq. ft. pricing being a horrible metric, and how it doesn't scale well.
Your claim is that your involvement in the job will yield $260,000 savings. Let's assume your hourly wage would have been $25, which is probably generous in most areas for inexperienced labor. This imputes your hands on contribution to be 10,400 hours of work, or 5 years of 8 hours a day, 5 days a week, 52 weeks a year.
I'm sorry if I seem to be negative, but your numbers simply do not add up.
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I deleted that last comment because It looked like it was placed in the wrong area of this thread.
Malcolm, fair enough with the builder’s joke. I’m looking for something sort of like Habitat for Humanity (it’s not in our area) or at least something like This Old House where they teach when it saves the homeowner money.
Patrick, I can make it work up to $100/ sq ft (fair enough with price per sq ft being a bad metric, let’s say the total cost of the build dividing out to $100/sq ft or less) and as small as 1000 sq ft, preferably at least 1500 (2000 was for room for extended family and to possibly add a long term rental to help our affordable housing shortage around here). Add the “Habitat for Humanity/This Old House” context to it plus a reduction of the builders fee. Hopefully that could help get me there. Also, I’d be willing to put in more than 8 hrs on a large portion of the days.
My loan will allow 2 years (maybe even more, haven’t asked) to build. I would like to get it done in 1 obviously.
I think you're going to have trouble pulling this off.
You have to look at it from the perspective of the other people involved. First, the bank. They make money by lending money out and getting that money repaid with interest. The biggest thing they care about -- really the only thing -- is making sure that they will repaid. The reason they insist on a licensed contractor is that they want to be sure the house gets built, and that if for any reason it doesn't, at any step in the process they can foreclose and sell whatever is there for more than they're owed on the loan. Reading your description I don't see a loan officer wanting to take on that risk.
There may be regional differences, but around here the bank requires that you have a fixed price contract with a contractor. They insist on that to minimize the risk of you getting over your head. Pivoting around to the contractor's point of view, you're asking him to take on significant risk. If this project goes into foreclosure the bank's going to sue him too. And he's not going to make much money, you've already signaled that you're cheap! (I'm kidding -- but only a little).
I don't think a construction loan is the way to go.
Insulatedcobber,
Unfortuately I have to agree with the reservations Patrick and DC have expressed - and add another: Where did the $50/sqft come from? The ballpark estimate of $180 you got came from the builder's experience of actual costs on projects. Does the $50 have a similar basis, or is it aspirational - meaning it's more like what you wish it will cost?
For better or worst, over the last decade or so both building codes and financing have made these types of self-builds using unusual assemblies almost impossible - especially if you aren't using your own money. I'm sorry this all sounds discouraging, but it's better to know up front what you are going into than getting part way along and finding yourself in a mess.
Martin and Malcolm,
Thank you for the Tomorrowland suggestion.
Insulated,
Your cob walls may be cheap, but you'll still need roofing, doors, and windows. And it's possible (not certain) that you'll still need a toilet, a bathtub or shower, kitchen appliances, a water heater, kitchen cabinets, flooring, electrical wiring, indoor plumbing pipes (water supply and drainage), a well pump or spring, a septic system and a driveway.
Wall costs have almost nothing to do with the cost of construction.
Using onsite raw materials might sound like it will save money, but it will probably end up costing more. Imagine for example that you want to build using onsite timber, and you have a heavily wooded lot. A regular build would order up whatever dimensional lumber was needed, have it delivered, and start framing.
Now think about the process using onsite timber: you have to fell the trees, you have to haul them to wherever you have your sawmill setup, you have to debark the logs, you have to set the logs up and square them in the mill, then you have to run planks. You have to repeat this process for each size of lumber you need for your project. AFTER you've done all of that -- and it's a LOT of work -- you can start framing.
All those extra labor steps are going to cost money, and time. Yes, there are people that have done this sort of thing, but they usually do it entirely on their own, or with groups of like-minded people. I think you'd find it very difficult to find any general contractor willing to take on a project like this, especially in today's enviornment where all the trades are super busy. No one will want the extra risk, and a super long duration project, when they could churn out lots of regular projects for more money, with less risk.
I think your best case scenario would be to contract someone on a time and materials basis, so that you assume all of the financial risk. Once you've done that, you need to understand that you have no cap on your potential expenses, so if your project drags on, you'll be burning through a lot of money.
I don't think that $50/sqft number is reasonable, either. That's even lower than the number we use commercially for warehouses, and warehouses have essentially NO finishes inside. It's the trim/finish work that eats up a decent chunk of money on a residential build...
Bill
So much of this sounds beyond unrealistic. You are destined to fail without massive reconsideration and it seems I’m not alone. Do you really think all the previous posters are wrong? Sorry.
I’m looking for something along the lines of Habitat for Humanity (not operating in our area), at least something like This Old House, they teach where it makes sense to save money. I’m basing my metric off of $5-$40/ sq ft for cob owner/builders and a $129/sq ft national average. If I could land anywhere up to $100/sq ft I could make it work.
Regarding finding a mentor/builder. My suggestion is to get a job in the trades. Learn how to do the work at least at a helper level and start to build a network of contacts. You'll meet people who might be willing to help you out at a reasonable cost when it comes time to do your own house, and you'll also gain enough experience on other builds to avoid costly mistakes on your own. One piece of advice I always used to give to my kids and sometimes, even my employees, was to always try to learn on someone else's dime.
This. Get a job working residential construction. Work on a house or two from when it's stakes in the ground to when the keys are handed over to the new owner.
Definitely good advice
Not meaning to pile on here or beat a dead horse, but Andy's advice above is fantastic. There really isn't a shortcut to proficiency in the trades - the time is what it is (that whole 10,000 hours thing very much applies here, too).
It sounds like the "mentor-apprentice" relationship you're looking for is best achieved by either enrolling in formal trades education (geared towards natural building, maybe) or finding a job in the trades (you'll be gaining great experience and make some money). The truth is, it's a really hard sell for a good builder to take on and teach one inexperienced person when the builder knows from the outset that the knowledge he or she is imparting won't be moving on to the next job. The benefits there really only move in one direction (which I think is why they make you pay for it when you go to school).
I believe one of the guys over at FineHomebuilding just finished building his own house - I'd recommend a quick Google and checking out that article (and I think he was on the podcast recently talking about it, too). I think there are a few really valuable lessons there, one of which is the idea that "being able to do something much cheaper on your own" sometimes isn't worth the tradeoff for the additional time it'd take. That project is definitely worth checking out.
Habitat for Humanity is a pretty good example of the sort of relationship I’m looking for with a builder (I know, everybody here so far has basically said I’m not going to find it). Natural building schools and working for a local builder are all great suggestions as well. I’m exploring all of these options. My goal would be to find a local builder willing to work with me like Habitat for Humanity primarily, along with small supplements of natural building school/working for a local builder.
insulatedcobber,
That's a useful analogy - and sort of what some of the comments on this were skirting around. You are looking for someone to subsidize your build as an act of charity. Fair enough, and I hope you find someone, but that's why you were getting so much push-back on your plans. It's not an apprenticeship, and there are no shortcuts that will reduce the budget to what you want. The only way this gets done is if someone decides to help pay for your house.
True. I do appreciate all the advice. Warnings of how hard it will be to find or downright impossible do help me to not have unreasonable expectations. I’m always amazed when I hear owner natural builders building their own straw bale/cob/rammed earth/earth bag etc. house for 5,000, 20,000, 50,000 etc. I figured, with the right steps, I could at least hit some sort of middle ground between this and a full budget mid size mid level finish custom home build. We’ll see. I’m shooting for this because I know I can always fall back on a small entry level finish (at the 180/sq ft from the builder) house on a smaller plot of land.
A lot of -- perhaps all of -- those stories you read on the Internet about people building their own houses on the cheap are just fantasy. I won't say the writers deliberately lie, but it's really easy to undercount expenses when you're doing a project that stretches over a long period. When I was a kid I used to love reading Mother Earth News, but as I grew older I realized almost everything in it was wildly unrealistic.
Habitat for Humanity is instructive. If you look at the houses they build, they are modest sized, standard construction and no-frills finishes. That's really the recipe for affordable construction.
If straw bale, rammed earth or earth bag really allowed you to build a cheaper house, wouldn't every house be built that way? Construction is all about cost containment. Even on most elaborate "money is no object" houses cost is still a concern.
A lot of those earthen home building techniques only work financially when you have a lot of free labor. This works in communal living arrangements, where you have a group of like-minded people working towards the goal of building a structure like this that they'll all share. You may potentially get some ideas from Earthship Biotecture along these lines.
If you're planning to go with a more conventional "help me build this, I'll pay you for your time, but when it's done it's mine" kind of project, the labor to use some of those earthen building techniques will likely more than offset the cost of materials involved. That's probably the biggest downside with those techniques. I question some of the other things advocated by people using those building techniques (notable longevity and energy efficiency), but that's not really the kind of info you're looking for in this particular Q+A thread.
You may want to try contacting the Habitat for Humanity people and see if they can refer you to anyone in your area that might be able to help you. I know the Habitat people have some travelling people that work with them periodically, and they probably have some contacts that might be able to help you.
BTW, I recommend you also look into reclaimed materials as another way to help to keep costs down on your project. You can get all kinds of reclaimed materials: insulation is a big one, but also windows, doors, flooring, even electrical stuff! The one thing I'd be careful of if you go this route is certain types of used circuit breakers. Stay away from anything Federal Pacific -- they went out of buisness for a very good reason. Stay away from anything that looks like it weathered outdoors at all too. Clean parts that don't make sound when you shake them tend to be OK, just cycle the toggle several times to wipe the contacts prior to putting used circuit breakers into operation.
Bill
Bill,
Thanks for those tips! We have a great rebuilding center here so that could be doable.
Spot-on analysis. And I'll add that a builder is probably the wrong person to be asking for charity, at least in a professional capacity. There days are full of homeowners trying to get them to do a little bit more than they agreed for the agreed-upon price, and subcontractors trying to do a little bit less than they agreed for the agreed-upon price.
Sounds like a great dream please keep us updated on how it works out.
I have a hard time seeing how or why a builder would work with you. To my ear it sounds like you are asking a lot from the builder and offering almost nothing for lot of headaches.
Your $50 a sqf goal for a custom home seems like a big stretch. Most custom homes builds will spend that much on windows, doors and roofing.
Walta
Habitat for Humanity is a good example. I could go up to $100 with the plot of land it’s planned for right now $150 with some other plots that are available. $50 is what I’m starting with based off of $5-40 for cob owner/builders and $129 for the general average.
It seems your full south windows will be too much. You need to do an energy model on this to optimize the amount of south windows. The south windows need a designed overhang, so they are properly shaded in the summer. Then the windows will loose too much heat in the winter.
You will also need walls for structure on the south side, Oregon has earthquakes. Your plan description sounds like an above ground New Mexico Earth ship, old 1970's building science thinking.
This old house is not = to Habitat. They seem to work on million dollar plus houses in the last 10 years.
I’m aware of the overhang. I have thought similarly to you in regards to the windows. Although, I explained it like this because this is what I’ve seen performing well from completed projects in our area. Any constructive advice appreciated. When it comes time, I do agree with an energy model for my specific building site. Right now, design is in the early stages of discussion. It will be permitted, so what has to be built in regards to earthquakes will be handled.
I mentioned This Old House because it looks like they teach the homeowner along the way but that just might be for tv.
I haven't watched This Old House in decades, but what I remember was the running joke that on the last episode of each season they would present the owner with the final bill and he would just about drop dead because it was two or three times what he had budgeted.
Years ago I volunteered on a lot of time to Habitat for humanity builds. I rarely recall seeing the soon to be owner on site and when they were it seemed like they were selecting paint colors and such. I never felt like the home owners were learning any building skills. Seemed to me they had their hands full paying the rent and feeding their kids so I had no hard feeling.
Walta
The only scenario I can think of where you would be part of the building scenario and be able to get a loan would be through modular building. They could bring in the shell and then you could be part of the finishing carpentry. Depending on your skill level this can involve as extensive as plumbing hvac and electrical yourself or at best you would be painting walls and drywalling. This would never drop down the price to 50 a square foot though. I wish I could find a builder that would only charge $50 square foot. As one poster put it you would need a time machine. I don’t think anyone here is discouraging you or being non constructive they are just being realistic
This type of construction (and low-cost dream) puts you more in line with the natural building community. It's not that green building advisor is particularly against natural building materials (and most would admit that they are very "green"), but it's a bit of different shades of green. Here's the contrast: I'm toward the "light green" side -- renovating a conventionally-constructed house with above-code levels of insulation and air sealing (using high-performance but otherwise conventional materials), triple-pane windows, air-source heat pumps, and grid-tie solar. My sister is more toward the "dark green" side -- dreaming of cob houses, composting toilets, rocket stoves, and off-grid solar. I'd say in general (although there's certainly lots of shades), the GBA community tends lighter-green, and the reactions you're getting here are generally from the perspective of people who build high-performance but otherwise conventionally constructed houses for a living.
I asked my sister for some "darker green" resources -- if you're not familiar with them, she said there's a natural building community on the permies forums. Also, she recommended the Cob Cottage Company -- she said they're great people and are one of the premiere groups developing & educating people on cob technology (and they're located in Oregon also). One nice thing about the natural building community is that it seems close-knit -- go get involved, learn by helping on some projects, and you'll probably meet people willing to help on your projects.
I will say that your 12000 square foot goal sounds enormous to people in that community (unless you're also talking about this being a home for an intentional community of 10 people!) -- seems like a lot of natural building projects are quite a bit smaller.
Also, from my limited knowledge, both cob and light straw clay are very labor-intensive, and also cannot be done too quickly -- cob, for example, needs to be allowed to dry adequately in layers. For this kind of project, my recommendation would be to frame a "pavilion" first -- get a foundation, a post frame, and a relatively conventional roof with generous overhangs. That gives you a dry place to work on the walls and such and store other materials.
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I agree, I've always thought of GBA as a community of high performance builders, and others trying to get up to speed on the newer energy saving technologies and construction techniques. The shared goal is usually to produce the most energy efficient structure possible, while still keeping the project commerically viable. We do see some of the more esoteric stuff periodically, but it's not the norm.
The builders that are trying to minimize their use of manufactured materials are a different group for the most part, but they do have some overlap. Those people tend to be off gridders too, but I know some GBA people also go that route. There are some common goals among both groups, but different specialties that aren't shared between the groups. I don't think there are too many builders on GBA packing earth into old tires to build walls, for example :-)
Bill
I would go through a build log that includes detailed costing and see where you can actually save money and what your final costs in the end will be.
This blog is a great start as it was pretty much a self build:
https://savingsustainably.com/project-budget/
https://www.greenbuildingadvisor.com/article/saving-sustainably-shingling-roof
My folks self built a simple 550sqft cottage on piers about 20 years ago and they certainly know how to watch the budget. The structure is a simple one story gable with 2x6 walls. The build ended up costing $70US/SQFT (about $115 in today's dollars), that did not include well drilling, septic or electrical service.
Last spring I was approached by a couple just down the road who wanted me to design a house for them. Based on their budget I told them they could afford about 1800sf. They replied that they wanted 3000sf (plus an 1100sf deck), that they had a friend who runs a saw mill, and another who is a builder who could do it for $175/sqft - something we haven't seen here in the best part of a decade. Having done what I could, I designed the house, they went in for a permit, and had the hole dug.
About six months have elapsed. The excavation is a pond, and they haven't bothered to pick up their permit as it's clear they have no chance of getting it built. A bit more realism at the beginning and they would probably be moving into their house early in the new year.
This confirms something I've been told and observed, which is that most of the cost of a house is baked into decisions that you've already made when you break ground. Or maybe decisions that you should have already made, or have made by default and don't know it yet. It's very hard to squeeze cost out once the build is progressing.
DC,
It may be different at the upper end of the market, but the houses I design or build don't have much fat on them. What is there to cut? Maybe the countertops could be downgraded? The roof go from metal to shingles? The possible savings that don't fundamentally affect the integrity of the house don't amount to much.
This is the case for commercial projects too. I tell my customers to make extra reviews of the plans first, to avoid changes later when things are in progress. In these cases, I would say you are never able to "squeeze costs out" after things start, but you sure can make costs go up! I had one project where the customer made so many changes during the project, and resisted committing to so many things (which caused scheduling problems, delays, and conflicts between trades), that their project was over budget by double. I warned them the entire time too. To their credit, they told me they should have listened to me at the beginning, and they didn't give me any hassle paying my consulting fees.
I like to say that part of my job as a consulting engineer is to make sure my customers never say "I wish we'd" or "If only we had" years after their project is complete. It's best to work out everything BEFORE starting.
Bill
Yeah, I would say if a person of ordinary abilities wants to contribute to the building of their house their time is probably best spent not in manual labor but in going over the plans. By plans I mean not just the blueprints, but materials schedules, budgets and calendar. Spend time making sure the various versions all agree with each other and making sure nothing is forgotten.
If you can get a few hours of help from a skilled person, their help might best be used in sanity-checking the plans.
True, unless someone owns the land or its in a rural area and/or doesn't care about resale value, the location dictates a large part of the build cost both in size of house and level of finishes. Many planning by-laws even have fits into neighborhood type clauses.
My planned build is an infill in a pretty high cost mature neighborhood. My build cost is already dictated by the neighborhood, unless I disregard resale value.
The rule of thumb I've heard is that it's probably an economic mistake to build a house that is either above or below the average price for the neighborhood by more than 15%.
Like you said, low cost made mostly from site sourced materials. Fully permitted and financed.
So why would you use these natural type, labor intensive methods to construct a home that could be built faster/better using conventional methods and cost less?
Your free labor will walk off (a common theme-see Amazon) from hunger, fatigue and low pay never to return and finish the project. But good luck!
When I was in the design process for my home, the engineer I worked with specialized in strawbale construction and suggested the possibility of signing on to a workshop type plan. She had been part of several projects like this where the homeowner "volunteers" their project for a strawbale workshop. The instructor (and possibly others) lead the workshop , which consists of future home builders like yourself, and supervise all aspects. I don't recall what the breakdown of cost was, but do remember that it was financially appealing. Of course, there's much more specialized labor required for the completion of the house that the workshop has nothing to do with.
Before all the discussions about building techniques, materials, or costs per square foot, you should consider the size of your house. Most people build way too big.
One great resource for designing a home are the series of books Called "The Not So Big House" by the architect Sarah Susanka (you can usually find then at your local library). She teaches various ways of downsizing what you THINK you need for what you actually need.
As mentioned, it is very hard to cut costs once construction has begun because all that's left to change are the finishes (a cheaper countertop, less expensive lights, etc).
Build smaller, and I would also suggest building your house in stages. Design it all now but make it so a bedroom could be added later. Put the framing you'd need for the addition into the exterior wall so that one day when you add on you don't have to rip out framing to put in a door (or put a window there and change it to a door later). Make it as easy as possible to add on later.
It's worth mentioning that the floorplan and general shape of the house can play into build costs. It's cheaper to build a square or rectangular house than one with lots of corners, for example. It's also a little cheaper to build a house where all of the dimensions work out into full sheets of material (which usually means 4 foot dimensional increments). You reduce labor by minimizing corners, and by minimizing cutting.
"Cost per square foot" is not a hard number, it's just an average for an area. You can do things to drive that number up, and you can also do things to drive that number down. If you're trying to minimize costs as much as possible, pay extra attention to to the layout as I described previously.
Since I was just in an Ikea today, I'll mention that I'm always intrigued by their "living in 567 square feet" example apartment layouts. It's impressive what you can do in a small amount of space if you're careful with your design, and you are clever with your layout.
Bill
I worked on a project with a great room with 16 ft ceilings. It was over budget and it got down graded to a "good" room with only 12" ceilings.
New plans & reengineering made it fit the budget.
I agree with the 2,000 sqft seems big. Perhaps build a smaller house with a big garage. Garages can be cheap if left unfinished on the inside.
Should GBA change its name to High Performance Building Advisor?
How about "Good Building Advisor" ?
I went down a similar path with my first house. I built a full scribed dove tailed log house, the vast majority of the materials used were locally sourced and milled wood products. The only things i subbed out were the excavation, plumbing and electrical. I even custom made the toilet paper holders and other small details.
During the build some lady came on site and asked me how much it cost to build a house like that, because she read in a magazine that you can build a log house for $5000. I told her that I had already spent over $1k in fasteners, and $2k in stains/paints, and I was not even close to done. She looked at me like I was lying.
I saved a pile of money doing it myself, and had a great life experience. But it was still expensive!
I may take on a similar project when I am closer to retirement, but I will go in with my eyes wide open.
I love the idea of your project, but listen to experienced voices. If in doubt, downsize the plans. This is the best way to save $.
That's a great rule of thumb, plumb_bob: cutting finishes and detailing and materials might save you 10% if you really use a hatchet, but the best way to cut costs nearly every time is to build less.
My brother in law built a rammed earth house in New Mexico years ago. It was possible because he had grad students working for free.