I live in a prefab home that was trailered in and placed on the basement with a crane. I visited the factory in Indiana, which was basically a lot of carpenters building homes inside of a warehouse.
My house is 1568 square feet and looks almost exactly like the picture on the website. The price from Rochester was $120,000. From the factory, the house was almost completely finished (drywall, bathroom, cabinets, etc). Carpeting/flooring was done after the house was delivered, as well as some customizations and modifications for code (sprinkler system).
$77/square foot.
There are tons of other costs with building a house on vacant land, but those are the same regardless of how the house is constructed.
Mighty Homes has some really interesting technology, but there is definitely a premium to be paid for it. It's really, really hard to beat the economics of stick-built construction. At least right now.
walrus01 1345 days ago [-]
One of the problems I ran into when researching 'manufactured homes' is that it's difficult to distinguish from the marketing materials, the homes which are built from the cheapest possible lumber, particleboard, MDF and chipboard. Such as: https://en.wikipedia.org/wiki/Clayton_Homes
And those which are built to a higher quality standard, indoors in a factory as you describe, but are not something that will begin falling apart after 5-10 years.
Unfortunately in many parts of the US and Canada any 'manufactured home' may be prohibited by zoning laws, because cities don't want more trailer parks. And they can be totally ineligible for the same rates of mortgage as a home built on site.
syedkarim 1345 days ago [-]
The term you are looking for is modular home—a house that comes in pieces and is finished on site, though smaller modular homes can be just a single piece. The big difference between the two is modular homes are put on a foundation, whereas manufactured (previously called mobile homes) housing is built on a frame that has temporary axles. If a manufactured house is set on a foundation, it might not be considered a manufactured home anymore.
The quality of the build can be good or bad for either type, though cheaper materials tend to get used in manufactured homes since cost is usually the driver on those homes.
imtringued 1345 days ago [-]
This doesn't surprise me. Metal 3d printing is more expensive than conventional manufacturing processes. It's primarily used to create shapes that are otherwise impossible.
The gif in the article shows a trivial L shape that could be extruded with a simple die. Granted the die would have to be quite large but a large scale 3D printer like the one shown isn't cheap either.
basch 1345 days ago [-]
Does anyone know of companies in the United States making cross laminated timber / cork hybrid prefabs? I thought these were pretty cool.
>There are tons of other costs with building a house on vacant land, but those are the same regardless of how the house is constructed.
When I was building, I quickly learned that the first $50-100k I was going to spend went entirely to preparing the lot for construction.
simonebrunozzi 1345 days ago [-]
Great point. Right now you can build in the insanely expensive San Francisco Bay Area for something between $400 and $500 per square foot. $330 is certainly not a great improvement.
jamestimmins 1345 days ago [-]
Have you written about the extra costs and challenges of building a house on vacant land? I'd love to read about that experience.
syedkarim 1345 days ago [-]
I have not, but only because it’s all been written about before. It’s pretty normal stuff: Bringing electricity out, digging a water well, installing a septic system, getting permits, calling the inspector. Some people have general contractors to manage all of this, but it’s perfectly reasonable to manage it all without a GC, who charges 20% on top of whatever is spent.
I live on 14 acres of ag-zoned land in a very suburban area not too far from Chicago (30 minutes without traffic). Maintaining ag-status is a pain in the ass and eats up way too much of my time.
mc32 1345 days ago [-]
Is it zoned for airstrips? It could be something useful if it could act as park and fly to midway (who knows maybe this makes no sense for that area).
syedkarim 1345 days ago [-]
I'm in the northwest suburbs and about 20 minutes away from O'Hare.
teruakohatu 1345 days ago [-]
> Maintaining ag-status is a pain in the ass and eats up way too much of my time.
What does this mean? Do you have to plant some crops to be considered ag?
syedkarim 1345 days ago [-]
Yes, that’s exactly what I do. I have a couple acres of pumpkins. A free pumpkin launch (by trebuchet) is included with each purchase.
OldHand2018 1345 days ago [-]
Do you have a website or other contact method? I'd love to come visit this fall (assuming you are open). I'd also like to talk about your experience, as I'd like to have a small ag-zoned house+farm not too far from Chicago. Right now we are learning via a garden plot in the city and hope to have the skills in place within a few years.
syedkarim 1344 days ago [-]
Sure, my email address is in my profile. You are welcome to come out anytime, though I’m no expert in any of this.
malandrew 1345 days ago [-]
What’s the benefiting of maintaining the ag-zoning?
syedkarim 1344 days ago [-]
I have 14 acres and my property tax bill is about $9000 a year. Virtually all of that tax is for the house and the one acre that it sits on. The rest of the acreage has an annual tax bill of about $100. The property adjacent to me is smaller and is vacant, raw land. They pay $22,000 a year in property taxes.
rbanffy 1345 days ago [-]
> "350-square-foot studio, starting at $115,000"
Pricing is not always a function of the cost, but a function of what the market will take. They also need to amortize all the investment they made on R&D.
syedkarim 1345 days ago [-]
Correct. But the article states that they offer a lower-cost alternative to conventional construction.
rbanffy 1344 days ago [-]
That's a very good point. Maybe they are comparing with options using the same materials.
madengr 1345 days ago [-]
Not to mention that $115k price almost doubles to $220k once they tack on the additional costs. I wonder how much of that are fees paid to government?
Animats 1345 days ago [-]
The homes are made of Light Stone, a thermoset composite material that hardens when exposed to UV light. - Mighty Buildings.
The material used is more interesting than making prefab houses this way. Lots of companies make prefab houses, many of which are better and cheaper than these. Being able to 3D print big, weatherproof parts is useful in itself.
"Light Stone" appears to be a name used by Mad Maker Filament for NatureWorks 3D870.[1] It's high-temperature PLA (polylactic acid), a better version of the plastic used with 3D filament printers. I'm puzzled at the use of UV lighting. That's not something normally done with PLA, but it's not unknown. Also, PLA is a thermoplastic (melts and re-hardens to the same form) as opposed to a thermosetting plastic (changes molecular structure when heated.) Did they find something that can be heated to make it soft, put in place, and then hit with UV to crosslink the strands, like the plastics used for dental fillings?
This is almost certainly not the same Light Stone. I'd wager a fair amount of money it's a UV resin-based extrusion setup that they mix themselves.
simonebrunozzi 1345 days ago [-]
A great segue question would be: what's the real environmental impact of "Light Stone", compared to cement, wood, or CLT, or others?
tootie 1345 days ago [-]
I was surprised by that too. All the human-scale 3D printed construction I've seen before used some form of concrete and not polymer.
Animats 1344 days ago [-]
3D printing in concrete remains more a curiosity and artistic device than a useful way to make strong concrete objects. There's no compaction.
Compare the Lil Bubba Curb Machine.[1] This is a simple slip-form device for making road curbs and such. You pour in concrete, and it pushes itself along by pushing concrete into the slip form. The concrete is compacted by the push, and a smooth curb emerges from the output end of the form.
Somebody should combine pumped concrete 3D printing with a compacting device like the Lil Bubba. Then you could get smooth surfaces, not things that look like stacked layers of toothpaste.
there is no way that anything PLA based is being used to build homes that will be out in the weather.
elihu 1345 days ago [-]
> The startup, which launched from stealth today and graduated from Y Combinator’s tech accelerator in 2018, developed a synthetic, lightweight stone material similar to Corian, a material sometimes used in countertops. As the material is printed and exposed to light, it creates a reaction that immediately hardens it. “It literally freezes in air,” says Solonitsyn. It can support its own weight, making it possible to print horizontally in the air.
This seems like the most interesting part; they're using a new material rather than just coming up with a new kind of 3D printer. The obvious follow-up questions are whether it's cheap enough, or strong enough, or environmentally sustainable to manufacture on a huge scale, and whether the material has a long usable lifetime and doesn't have flammability issues or off-gas any unpleasant chemicals.
simonebrunozzi 1345 days ago [-]
> Correction: We’ve updated this article to clarify that the units currently under construction by Mighty Buildings are not entirely 3D-printed, but the next iteration will be.
Very important correction.
tintor 1345 days ago [-]
Fake it, 'till you make it.
elihu 1345 days ago [-]
I think that an important missing piece in realizing the full benefit of machines that print houses is software that does automated building design.
The way most suburban residential construction is done these days (at least in the U.S.) is to start with a large area, split it up into relatively homogeneous lots, and flatten them out as much as possible so that they fit the requirements of one of some set of floor plans that were designed without regard for any specific lot.
The alternative to this is to do custom designs that take the considerations of particular lots into consideration, like the position of the sun during the day, the direction of the best views, layout of the yard, etc.. This is expensive and hard to do on a large scale, because you can't amortize the cost of the architect over multiple buildings.
Another alternative is to have a software package that takes a given lot and generates a floorplan optimized for that lot (and the needs of the buyer, if known). This is a hard problem, but I think it gets easier, or at least more interesting, when combined with machines that can build houses. With 3D printing, the design can be as complicated as you want, with little impact on cost. You can have funny-shaped walls that aren't at right angles with each other, vaulted ceilings, gothic arches, flying buttresses, or any kind of ornamentation or functional feature without regard for having to consider the difficulty of expressing the design to human workers. If done well, it could be a major step forward for well-designed residential construction -- you get a custom building on every lot that's optimized to match the site rather than forcing the site to match the builder's requirements, and the marginal cost of the design work is low (probably more than zero, since you'd need a human to review the design and possibly negotiate with customers).
alteriority 1345 days ago [-]
Was just listening to a podcast today that went over this, a different pre-fab house startup whose killer app sounds like basically the software you're describing, or at least the first steps towards it.
(Full disclosure, I haven't looked any further into it or even finished the podcast, so I'm not sure how much of that description is straight hype).
> You can have funny-shaped walls that aren't at right angles with each other, vaulted ceilings, gothic arches, flying buttresses, or any kind of ornamentation or functional feature
You're going to have to allow for a lot more negotiation with customers once you start adding "frills" - one reason that houses built in bulk are so plain is that tastes vary hugely and you have to bet on what flavor is going to be popular right when you want to sell them all. Flourishes are the kind of thing that will rarely make a sale but will easily break it.
elihu 1345 days ago [-]
Sure, but if one were to design the software to construct houses in a distinctive style that a lot of people like, then it probably won't be too hard to find people willing to buy.
Part of the developer's "brand" could be to invent new and interesting styles without getting too carried away with ornamentation for its own sake, or adding features that most people don't want.
Flying buttresses and gothic arches were kind of a silly example; probably most houses wouldn't benefit from looking like Notre Dame (especially if everyone started building their houses to look that way), but there may be other styles that would look nice and would fit well into their environment, but which wouldn't catch on now because it's too complex and therefore too expensive to build.
notahacker 1345 days ago [-]
It's not difficulty in planning that's responsible for the ubiquitous right angle, it's the tendency of people to like familiar features and want their furniture to fit (they're also often fond of materials not particularly amenable to 3D printing). Architects would love to design the sort of curvaceous things from concrete, steel and glass they went to architecture school to admire, but the need to sell the houses gets in the way.
I'm struggling to see procedural generation of the designs as doing anything but subtract from the ability to conceive 'distinctive style a lot of people like', given that architects are people with likes, can talk to prospective purchasers about their likes and understand at a high level how people might use [or not use] particular design features and what designs regulators might reject.
Neural networks, on the other hand, produce outputs which are just a function of their inputs. Procedural building generation is what designers of 3D worlds use for the bits whose appearance they don't care enough about to detail by hand. The one place software design might lead to improved efficiency is randomising features for McMansions on a street from a simple library of squares and automatically generating the docs...
djrogers 1345 days ago [-]
> Compared to an average house in California, the new homes cost as much as 45% less.
> The company is making homes in a variety of sizes, ranging from a 350-square-foot studio (starting at $115,000,
These two statements do not compute. I’m in the process of planning an ADU, and $115k for 350sq ft is smack dab in the middle of the ‘really nice’ prefab ADUs in the Bay Area, and as much as 50% higher than the less expensive options.
If these truly were cheaper, I’d be willing to take a risk on it.
titanomachy 1345 days ago [-]
Probably, they are taking the average over all homes built rather than just prefabs.
robomartin 1344 days ago [-]
I would be interested in learning more about how it is that YC accepts a company like this into the program, which, by definition, excludes others.
I place 3D printed homes right up there with flying cars. It makes for great futuristic articles, sure, yet, outside of corner cases nobody wants or needs a 3D printed house or a flying car. One could make an argument that these are places where dollar bills go to die and will be so for twenty-five years or more.
I am puzzled because of notions such as product-market fit, traction, and “build something people want”.
Outside of that, anyone with experience in construction can rattle-off at least a dozen ways for which a 3D printed home could be undesirable.
Even better, anyone with experience dealing with construction regulatory bodies (Building and Permit, inspections, zoning, planning, fire) knows full-well how much of a surreal nightmare this can become.
As a simple example, LA County Building and Permit added six months and at least $50K to my solar energy project simply because it didn’t fit within checkboxes the people I was dealing with were used to. Trying to introduce materials not on the approved lists could take decades and millions of dollars. I learned more about this than I care to admit.
So. Yeah. Why?
JoeAltmaier 1345 days ago [-]
Isn't a large part of house building, installing the plumbing and electrics? Is this handled by 3D printing? Or is it just the framing that is accelerated?
I'm thinking this may be a more expensive prefab approach, and may not be better than current approaches.
Very nice. Having worked in home construction weekends and summers to pay for about half of my college, any technology that can reduce the labor and time to build homes, especially if it's cheaper, is a winner.
Rendered at 03:43:11 GMT+0000 (Coordinated Universal Time) with Vercel.
$330/square foot is not cheap.
I live in a prefab home that was trailered in and placed on the basement with a crane. I visited the factory in Indiana, which was basically a lot of carpenters building homes inside of a warehouse.
https://www.rochesterhomesinc.com/tiptown
My house is 1568 square feet and looks almost exactly like the picture on the website. The price from Rochester was $120,000. From the factory, the house was almost completely finished (drywall, bathroom, cabinets, etc). Carpeting/flooring was done after the house was delivered, as well as some customizations and modifications for code (sprinkler system).
$77/square foot.
There are tons of other costs with building a house on vacant land, but those are the same regardless of how the house is constructed.
Mighty Homes has some really interesting technology, but there is definitely a premium to be paid for it. It's really, really hard to beat the economics of stick-built construction. At least right now.
And those which are built to a higher quality standard, indoors in a factory as you describe, but are not something that will begin falling apart after 5-10 years.
Unfortunately in many parts of the US and Canada any 'manufactured home' may be prohibited by zoning laws, because cities don't want more trailer parks. And they can be totally ineligible for the same rates of mortgage as a home built on site.
The quality of the build can be good or bad for either type, though cheaper materials tend to get used in manufactured homes since cost is usually the driver on those homes.
The gif in the article shows a trivial L shape that could be extruded with a simple die. Granted the die would have to be quite large but a large scale 3D printer like the one shown isn't cheap either.
https://www.pslcomp.com/projects-catalog/houses-from-corkbea...
https://www.pslcomp.com/construction-technology/glued-cork-b...
When I was building, I quickly learned that the first $50-100k I was going to spend went entirely to preparing the lot for construction.
I live on 14 acres of ag-zoned land in a very suburban area not too far from Chicago (30 minutes without traffic). Maintaining ag-status is a pain in the ass and eats up way too much of my time.
What does this mean? Do you have to plant some crops to be considered ag?
Pricing is not always a function of the cost, but a function of what the market will take. They also need to amortize all the investment they made on R&D.
The material used is more interesting than making prefab houses this way. Lots of companies make prefab houses, many of which are better and cheaper than these. Being able to 3D print big, weatherproof parts is useful in itself.
"Light Stone" appears to be a name used by Mad Maker Filament for NatureWorks 3D870.[1] It's high-temperature PLA (polylactic acid), a better version of the plastic used with 3D filament printers. I'm puzzled at the use of UV lighting. That's not something normally done with PLA, but it's not unknown. Also, PLA is a thermoplastic (melts and re-hardens to the same form) as opposed to a thermosetting plastic (changes molecular structure when heated.) Did they find something that can be heated to make it soft, put in place, and then hit with UV to crosslink the strands, like the plastics used for dental fillings?
[1] https://www.natureworksllc.com/Products/3D-series-for-3D-pri...
Compare the Lil Bubba Curb Machine.[1] This is a simple slip-form device for making road curbs and such. You pour in concrete, and it pushes itself along by pushing concrete into the slip form. The concrete is compacted by the push, and a smooth curb emerges from the output end of the form.
Somebody should combine pumped concrete 3D printing with a compacting device like the Lil Bubba. Then you could get smooth surfaces, not things that look like stacked layers of toothpaste.
[1] https://youtu.be/NJZMpu4MKn8
This seems like the most interesting part; they're using a new material rather than just coming up with a new kind of 3D printer. The obvious follow-up questions are whether it's cheap enough, or strong enough, or environmentally sustainable to manufacture on a huge scale, and whether the material has a long usable lifetime and doesn't have flammability issues or off-gas any unpleasant chemicals.
Very important correction.
The way most suburban residential construction is done these days (at least in the U.S.) is to start with a large area, split it up into relatively homogeneous lots, and flatten them out as much as possible so that they fit the requirements of one of some set of floor plans that were designed without regard for any specific lot.
The alternative to this is to do custom designs that take the considerations of particular lots into consideration, like the position of the sun during the day, the direction of the best views, layout of the yard, etc.. This is expensive and hard to do on a large scale, because you can't amortize the cost of the architect over multiple buildings.
Another alternative is to have a software package that takes a given lot and generates a floorplan optimized for that lot (and the needs of the buyer, if known). This is a hard problem, but I think it gets easier, or at least more interesting, when combined with machines that can build houses. With 3D printing, the design can be as complicated as you want, with little impact on cost. You can have funny-shaped walls that aren't at right angles with each other, vaulted ceilings, gothic arches, flying buttresses, or any kind of ornamentation or functional feature without regard for having to consider the difficulty of expressing the design to human workers. If done well, it could be a major step forward for well-designed residential construction -- you get a custom building on every lot that's optimized to match the site rather than forcing the site to match the builder's requirements, and the marginal cost of the design work is low (probably more than zero, since you'd need a human to review the design and possibly negotiate with customers).
(Full disclosure, I haven't looked any further into it or even finished the podcast, so I'm not sure how much of that description is straight hype).
Episode: https://www.stitcher.com/podcast/founders-fund/anatomy-of-ne...
Company in question: https://www.buildcover.com/
You're going to have to allow for a lot more negotiation with customers once you start adding "frills" - one reason that houses built in bulk are so plain is that tastes vary hugely and you have to bet on what flavor is going to be popular right when you want to sell them all. Flourishes are the kind of thing that will rarely make a sale but will easily break it.
Part of the developer's "brand" could be to invent new and interesting styles without getting too carried away with ornamentation for its own sake, or adding features that most people don't want.
Flying buttresses and gothic arches were kind of a silly example; probably most houses wouldn't benefit from looking like Notre Dame (especially if everyone started building their houses to look that way), but there may be other styles that would look nice and would fit well into their environment, but which wouldn't catch on now because it's too complex and therefore too expensive to build.
I'm struggling to see procedural generation of the designs as doing anything but subtract from the ability to conceive 'distinctive style a lot of people like', given that architects are people with likes, can talk to prospective purchasers about their likes and understand at a high level how people might use [or not use] particular design features and what designs regulators might reject.
Neural networks, on the other hand, produce outputs which are just a function of their inputs. Procedural building generation is what designers of 3D worlds use for the bits whose appearance they don't care enough about to detail by hand. The one place software design might lead to improved efficiency is randomising features for McMansions on a street from a simple library of squares and automatically generating the docs...
> The company is making homes in a variety of sizes, ranging from a 350-square-foot studio (starting at $115,000,
These two statements do not compute. I’m in the process of planning an ADU, and $115k for 350sq ft is smack dab in the middle of the ‘really nice’ prefab ADUs in the Bay Area, and as much as 50% higher than the less expensive options.
If these truly were cheaper, I’d be willing to take a risk on it.
I place 3D printed homes right up there with flying cars. It makes for great futuristic articles, sure, yet, outside of corner cases nobody wants or needs a 3D printed house or a flying car. One could make an argument that these are places where dollar bills go to die and will be so for twenty-five years or more.
I am puzzled because of notions such as product-market fit, traction, and “build something people want”.
Outside of that, anyone with experience in construction can rattle-off at least a dozen ways for which a 3D printed home could be undesirable.
Even better, anyone with experience dealing with construction regulatory bodies (Building and Permit, inspections, zoning, planning, fire) knows full-well how much of a surreal nightmare this can become.
As a simple example, LA County Building and Permit added six months and at least $50K to my solar energy project simply because it didn’t fit within checkboxes the people I was dealing with were used to. Trying to introduce materials not on the approved lists could take decades and millions of dollars. I learned more about this than I care to admit.
So. Yeah. Why?
I'm thinking this may be a more expensive prefab approach, and may not be better than current approaches.