WikiHouse – Open source, modular, wood based, zero carbon housing
wikihouse.cc
wikihouse.cc
First, looking through their design guide (https://www.wikihouse.cc/guides/design), the only thing they mention is that space (32mm in walls, I guess, and 70mm under ceilings) is provided.
Given that the plumbing, electrical, ventilation, appliances, etc. are the majority of the cost of a home, I find this a bit odd. A typical American full bathroom costs something like $5k to $20k (and up... way up) depending on the quality. A kitchen can cost multiple times more. Sure, you can build them cheaper, but that's the rub... most people who are in the market to purchase a home don't want low-end bathrooms and kitchens. Or windows. Or lighting. Or wall fixtures. Or anything really.
Second, IMO, the problem with affordable housing is not a construction cost problem. We can build small, livable (for various definitions) homes for $50k (or less) today, ignoring land costs. But the regulatory costs, the land costs, the market demands all make building such homes a non-profitable endeavor. Why build 20 $50k homes on the land and make $200k profit when you can build 10 $500k homes and make $1mil in profit?
The affordable housing crisis in the America do not have a technical solution, only a socio-political one. And since nearly all the power related to zoning, building costs, etc are managed at the local and state level, that means engaging with local politics.
Also, what's the soil like where you're building those $50k homes? I've often seen that being spent just on the foundation.
That said, I'm not sure this construction method is cheaper than existing similar techniques like for example structural isolated panels.
And taxes, and a myriad of other things that have nothing to do with actually building the thing.
Lots of factors contribute to all this and like anywhere it's always 'location, location, location', but outside a few major cities and popular holiday locations I think it's probably pretty cheap - in relative terms.
[1] https://en.wikipedia.org/wiki/Area_and_population_of_Europea... [2] https://www.researchgate.net/figure/Secondary-property-owner...
Not sure I agree with this. If we assume a labor at a rate in the order of 1 worker-hour per square foot (this is highly variable, from 0.5 to 2 hr/ft^2), a 2000 sqf home would require 2000 hours. At minimum wage ($15/hour) that means $30K, just for labor. This does not include concrete, lumber, stucco, sheetrock, electrical, HVAC, plumbing, appliances, landscaping, etc. It also does not include permits and design fees. And of course, assuming $15 per hour would not be accurate at all. By the time you get a contractor involved and various trades you are paying significantly more than that, perhaps closer to $75 per hour on average. That gets you up to $200K, again, just in labor costs.
DIY is a different matter. And yet, it isn't. At some point opportunity cost comes into the equation. It would be silly for me to DIY a home until I am retired or unemployed. The loss of income --opportunity cost-- of devoting thousands of hours to home-building would be massive.
If we are talking about building homes at scale, except for some very specific locations and types (pre-fab?), I am not sure you could build something for $50K these days. For example, I have personally had to deal with LA County's Building for permits and plan-checks for my 13 kW solar array (yes, I DIY'd that). They easily added $50K, if not more, to my budget without reason or justification. The most grotesque example of this is that they made me put in 64,000 lbs of concrete into the footings for my ground-mount structure. An architect friend of mine told me I could support a four-story building with that amount of concrete. Why? Nobody knows. Once the plan checker made that decision there was no way to reason with him. Power trip? It was death by a thousand cuts.
Low-cost building is something like $85 a square, so 50k gets you about 600 square. It is totally doable and that's with "current" setups (these are often built as "cabins" etc.
But the permits and other things destroy them (which is why so many "tiny homes" are technically mobile homes because then you just deal with the DMV).
And you can buy brand new homes including land around here for $300k so I suspect that they didn't cost $200k in labor. But maybe they do?
The truth of the matter is, as a percentage of the population, very few people live in 600 square foot homes. This is particularly true in the case of families. That's where you really have to start talking about double that space.
Anyhow, all-up home construction via traditional means is not cheap. These days transportation costs likely add a non-trivial amount of money to the total. Costs do vary across the country, and so does median income.
It would be interesting to find a comparison of construction costs of the kind of home the average family is looking for to the median family income for the area in question.
I don't even know if many people are building 1 bedroom houses anymore; those only seem to show up as condos now and then.
Everything is built as a three bedroom and so all you have as an option is three bedroom.
You may turn every block into kwaloon walled city and there will still be housing shortage.
I am not against density - I am fond of European 6 story buildings. But you have a fundamental demand problem. The big cities are bleeding dry the rest of the countries.
At the population density of Kowloon in 1987, 1,255,000 per square kilometer, and today's population of 8 billion people, it would only take 6375 square km to house everyone.
That's less than five cities the size of Phoenix, Arizona.
Reasonable urban population density -- the kind where there is still green space and buildings are mostly just a few stories high -- would be about 7500 per square km, about 1.1 million square km for the world population. That sounds like a lot, but it's only about one tenth the metro area of Paris.
There is a clean water problem. There is a good sewage treatment problem. There are energy delivery problems. But people will happily live in much denser arrangements than they do on average, and cities make all of the other problems more efficient to deal with. These are policy problems.
It's a chicken-and-egg problem, made worse by people who want to not pay for the infrastructure and maintenance.
If you step back into southern Brooklyn, Queens, the Bronx, the prices go down to reasonable, while still being within < 1 hour commute by public transport from the downtown area.
13,024,518 people, 18,940.7 km2
I don't understand this comment. This is the same profit margin. You invest 1 million (20 * 50k) and make 20% (200k) or invest 5 million(10 * 500k) and make 20% (1 million).
Depending on the amount of initial capitol you want to invest you may choose one over the other.
Homeowners benefit because it drives up the prices of homes, which has become one of the most important financial investment tools to normal people in this country.
If you, as a single household, plan to build a 50k house on your land, you might be unable to find someone to build it for you.
Of course in larger cities/projects with a single developer reselling units it's a bit different.
As I said, that's how I'm reading it.
Even if they have the same profit, o ly one of those strategies scales to allow you to pump more money in and get more money out without significantly changing the resources required to accomplish it.
You have to connect to water, sewer, power (or build a well and septic), you still have to get it permitted and inspected, etc, etc, etc.
It's a walmart "Neighborhood Market" which looks like a grocery store to me. There's even pictures of the inside.
The nearest grocery stores appear to be on the other side of the highway, and like an hour's walk from inside the neighborhood. Although literally no one here is walking to Trader Joe's. Just having a Trader Joe's here kind of implies that.
I'd be surprised if there are many suburban areas that are more than 5/10 miles from "stores" for some value of store. Taking some central place of Ridglea gets me a 2 mile walk to Walmart. But there are no sidewalks.
Your chance of finding a sub-dividable lot in a suburban area is essentially 0.
- Standardising on screw pile foundations. Standard concrete foundations are often be about 30% of the build cost, with the quantity of earth removed and cement used it's a massive part of the carbon footprint of a home. For a "light weight" timber construction, screw piles are the future.
- Having services recesses and notches built into the panels, and there is no need to batten the internal walls for boarding. this will increase the speed of construction significantly.
- Being an "Open" standard allows any timber frame or prefab construction company to adopt it.
My one concern (I wouldn't go as far as criticism) is that the panels have a somewhat complex manufacturing process by having to be CNC machined. Realisticly they almost always will be, but I would have liked to see the panels designed to be constructed a little more simply - you will always have to make changes on site.
I wander why they went with ply over OSB, they have similar structural properties but OSB can be cheeper.
My biggest concern with this system is given this system's "tightness" to water vapor (similar to SIPs), all of the same issues with mold and related air quality are inherited. If structures don't breathe they rot. i
Building sciences are both fun and fraught with peril. I'm somewhat excited and cautiously optimistic about Boxabl from a housing manufacturing perspective.
OSB is a fine air barrier, and most water vapour volume happens through air leaks. Vapour diffusion tends to be a smaller percentage:
* https://www.youtube.com/watch?v=FXXgjvOJcYI
The main place that vapour concentration really becomes a problem is at the highest point of the house (e.g., ridge):
* https://www.buildingscience.com/documents/building-science-i...
The main point is to not have your condensing surface on the inside of your structure:
* https://www.buildingscience.com/documents/insights/bsi-001-t...
Which is why so many jurisdictions are encouraging / mandating external insulation. When the sheathing is the coldest surface, of course there's going to be condensation, but if it's the same temperature as the inside air how would moisture accumulate.
> If structures don't breathe they rot.
If structures don't dry they rot. There are plenty of of <1.0 ACH@50 structures that do not "breathe" that have no moisture/rot issues because they take care of water mechanically, e.g., ERV/HRV and (whole house) dehumidifiers.
In theory vapor accumulation is only really problematic in the overhead plenum spaces. In actual practice (setting aside acute water ingress) 100% of the time moisture problems start in the crawl space and then spread to the plenum.
Yes absolutely it is possible to design complex interlocking systems that at least in theory both provide high efficiency sealed construction and control moisture. In practice the complexity of these systems is sufficient that even top-end contractors frequently run into issues that lead to full blown abatement projects. There is also the minor issue of what happens if all of these systems aren't subjected to aggressive inspection regimes and/or a structure goes a significant amount of time unoccupied. The one thing all of these super high-efficiency sealed systems have in common is they quite literally tear themselves apart if neglected or the power gets turned off for any meaningful amount of time.
The statement "If structures don't dry they rot" is absolutely true, but only in the context of traditional lumber products that are comparatively resistant to rot in the first place and are capable of weathering swell/shrink cycles without falling apart. Highly engineered products degrade aggressively just by getting damp in the first place as swelling wood fibers break down bonds with the adhesive that's holding the material together.
I absolutely stand by my original statement that OSB shouldn't be code-compliant and with the exception of shitty flat-pack furniture has no business anywhere in a home.
> In theory vapor accumulation is only really problematic in the overhead plenum spaces. In actual practice (setting aside acute water ingress) 100% of the time moisture problems start in the crawl space and then spread to the plenum.
Which is a good argument for conditioned crawl spaces.
* https://www.buildingscience.com/documents/bareports/ba-0401-...
Shit is wack yo. Perfectly usable houses are remodeled all the time.
I hate OSB so much. And it no longer is that much cheaper than plywood, which still can die in water but at least doesn't die immediately.
* https://www.greenhomeguide.com/askapro/question/i-m-concerne...
* https://greenhomeguide.com/askapro/question/we-have-osb-that...
Unless you're using planks for siding and your flooring, you're going to have to use some kind of glued product product. Further your OSB is generally behind your drywall (sheet rock, gypsum) which can act as an air barrier.
Ideally you should have an HRV/ERV that exchanges the air in your dwelling constantly.
The fact that you have to cut that many backflips just to get the stuff to work should tell you something. Once it finally does get wet all hell breaks loose because OSB cannot tolerate wetting cycles in the same way plywood can.
If you're ever curious about just how big the gap in durability is here's a free demonstration: next time you see a new house going up stop by after the framing crew has the place sheathed and ask for a small scrap of OSB sheathing and plywood they have sitting in the scrap pile. Take both home and let them sit out in the yard for six months. The plywood will warp a bit, and it might discolor. The OSB will disintegrate unless you live in a desert.
1850s-1960s: Termite damage followed by rot. This time frame is notable for ready availability of dense, tightly grained building materials. Lumber from this time period shrugs off all but the most egregious wetting cycles. So what happens is high humidity attracts termites which break down the structure. This in turn gives rot a plate to establish a foothold and spread (slowly).
1970s-1990s: This period is notable for a steady decline in quality of building materials and introduction of first and second generation engineered products. First-to-market siding products, condensation issues due to the aluminum craze in the 80s, and material adhesives edging out toward the end of their life expectancy all contribute to problems with mold/rot. Looser grained building materials also mean that when a problem is present it will quickly spread to larger areas of the structure than older materials would permit under similar conditions.
2000-2010: Easily the absolute nadir of home building in the US. The industry saw a massive influx of "budget" engineered materials, with no substantive changes to code to address the deficiencies of these materials. My personal favorite from this era include OSB siding that turned into a kitchen sponge whenever the paint layer was breached.
2010-present: same as it ever was. The market is still flooded with engineered materials that have a fraction of the life expectancy of more traditional materials. Building codes have largely caught up with the obvious limitations of these materials, however now the biggest issue is as a nation we are short two full generations of trained craftspeople in the construction industry and as such installation errors are rampant. This leads to more and bigger issues, bigger abatement projects, and in significantly newer homes. Case in point: a pinhole leak in a caulk seam on a window surround that resulted in all of the structural members surrounding that window, the wall cladding, the sill beam, a section of the floor, and several joists rotting out in short order. Root cause: didn't use plywood. Engineered sheathing acted like an enormous sponge both retaining and broadcasting moisture to all of the surrounding materials.
So yeah, you're not wrong inasmuch as according to theory and per code it is within the realm of possibility to use these construction methods and materials successfully. In practice, however, the least competent subcontractor on any given jobsite presents a hard ceiling to what one can get away with. You design a fault-intolerant system that has any flavor of complexity to it's installation and odds are good someone's going to screw something up. The Achilles Heel of modern vapor tight building systems is the fact that houses leak. Either through incompetence during the initial build or breakdown of materials over time all houses leak. Whereas older construction methods would tolerate this to varying degrees, newer systems do not.
- Hardwood timber framing
- Stone or masonry curtain wall from the foundation to the bottom of the window sills.
- Fully sealed crawlspace with inline registers broadcasting conditioned air into the space
- Insulate the curtain wall instead of the interstitial space between floor joists
- Standard soffit-to-peak venting in the attic space
- Two layers of plywood subfloor separated by a layer of tar paper
- Double layered sheetrock on all interior walls
- Wall-to-wall sheet vinyl floor treatments in all of the rooms where water is a thing.
- 3/4" hardwood flooring everywhere water isn't a thing.
- Passive/active solar combo meal on the roof to offset any efficiency losses incurred by "loose" construction methods
- Temperature & humidity sensors in the crawl space & plenum
- Wood window frames and sills. Modern plastic window frames and sills are excellent at hiding a problem until it's turned into a $50k project (see also: aluminum siding). By comparsion wood trim acts as a bellwether. I'd much rather have to scrape, recaulk, and paint a window than be looking at deconstructing an exterior wall that's rotted to the foundation.
Doesn't this risk any water that does end up getting in, to accumulate and cause more damage over time since there's no route for it to dry out?
I was always taught in my building science courses to put the water/air/vapour control layer inside the wall, before the insulation, so vapour can dry out from both sides.
If you really want to rot a floor though the absolute best A+ gold star method for doing so is adding a gas log fireplace with surround. I had a house a couple years ago that had moisture from the flue pooling inside the surround and under the unit. Rotted through 3/4" red oak hardwood flooring, 2 layers of 3/4" plywood, and bit off the top 4" of the 2x8 joists under the unit. Interior space was a solid sheet of black mold. That was one of those bag-the-room negative air pressure break-out-the-space-suits jobs. Six months later I was on a job where condensation off another gas log flue pooled inside a surround and got into the OSB cladding, then wicked 9' straight up. Only time I've ever seen cedar siding actually rot. We ended up having to cut the entire fireplace surround and a portion of the roof off the side of the house and rebuild it studs and all. Never a dull moment I tell ya.
> ... and the floor treatment rejects both vapor and spills.
That's a good point I didn't consider. Drying out the inner surface works well for interior vapour that gets into the enclosure, but won't handle spills, or standing water well.
>Which material is better, ply or OSB?
>Ply is lighter and generally better structurally but more expensive. OSB is cheaper but heavier. With the recent research on WikiHouse Skylark we did test both materials, but in terms of the full spanning floor beams it’s clear ply offers advantages in terms of strength but also because it’s lighter it’s easier to move and carry. A hybrid approach is also a possibility.
I feel this way about the current trend in plant-based meat replacements. I’ll trust the hype about lower carbon footprint, but they take food production further into industrialisation and profit motive territory which was, in part, how we got into this environmental crisis in the first place.
There are also better ways for agriculture which can regenerate soil, maintain biodiversity while at the same time harvest more.
The places where industrial agriculture has taken off, that seems not to be the story. Grandparents in China are thrilled to see their children working city jobs. It's a hard life still, but much easier than they had.
> regenerate soil, maintain biodiversity while at the same time harvest more.
I very much want those things. And corporations do sometimes make stupid decisions. But it's hard for me to believe there are such free lunches on a large scale. If there were, some enterprising soul ought to go start a business exploiting them, make a killing, put Monsanto out of business, etc.
Also there are many potential biotech revolutions - like China developing rice that can use salt water - if our crops could use seawater like the mangroves, that wouod be huge.
Another massive thing, is perrenial crops - meaning you dont have to plant them every year. There are perrenial cousins of our staple foods like wheat, but firstly they are harder to automatically harvest/manage, secondly they do not benefit from thousands of years of selective breeding. So we gave to invest massive amounts of money to ger their yields up, and even if you do, there is no guarantee consumers will eat them - they taste a bit different
Fun fact: Italians hated tomatoes for centuries.
https://lithub.com/unhealthy-smelly-and-strange-why-italians...
When most corporate leaders don't care what happens 2 years from now?
Unless you think cavemen shouldn't have burned sticks for warmth out of concern for CO2 emissions, the way out for humanity will be through (further technological gains enabling more energy expended per capita, hopefully cleanly), not backwards.
The problem with that is it's only one man that gets the benefit.
Yes, I'm twisting your words a bit. The point I'm making is that these profit motives tend towards capital hoarding by individuals. _That_ process tends towards selfish decision making where the only long-term benefit is the individual and their family, often at the cost of short and long term damage or hinderance to other people and the environment. I confess I make many such decisions myself, but it's very hard not within our current economic system.
I'm not arguing for a return to some imaginary glory projected onto images from the past at all. I'm trying to feel out ideas for future systems more of us can engage with comfortably, which don't promote the double hit of individual-focused power imbalances and environmental damage.
If you want to go all in on modular, wood based, zero carbon housing then learn how to build a timber frame house. If you really want zero carbon you can use only hand tools and harvest your own trees.
Wikihouse seems more for people who want to buy something off the shelf, pretty much a kit house. That's not a bad thing since it takes a lot of effort to build something as big as a house and lots of people don't want to do that. But I don't think this should be sold as a solution for DIYers since the existing methods already satisfy the listed requirements.
What you're glossing over here is that about 10-15% of the timber you buy to frame a site-built house is wasted (ad-hoc cuts, bracing, jigs, etc.) and thrown into a dumpster.
If a house is pre-planned, you can use a machine that cuts each board to length, and join the ends of each board using basic joinery processes that aren't practical when building a site-built home. You can pre-fabricate things like trusses and wall segments so you (or your workers) aren't driving 100k fasteners to fabricate something a robot could build in 1/10th the time.
> A typical WALL block weighs around 40-60kg and can generally be carried by two people.
They're a little light on detail about how these wall segments join and seal to each other so that could be a bunch more work. All this is considering you'd be able to get pre-manufactured blocks from somewhere, if you had to CNC and assemble them yourself then the labor is off the chart.
aren't prefab trusses readily available these days? i feel like i've seen plenty of trailers hauling stacks of 10 timber trusses down the road.
we've also got prefab homes (not mobile/trailer/whatever homes), with modules assembled in factories and brought together at the site. unfortunately they seem to carry class connotations here in the US.
Why on earth can't power tools run off renewables? And even hand tools/nails/ bolts etc. have embedded CO2 emissions.
[0] https://www.amazon.com/s?k=house+framing&crid=ZT0KPA5JG1EY&s... [1] https://www.youtube.com/results?search_query=house+framing [2] https://www.habitat.org/volunteer/near-you
https://www.youtube.com/c/HouseImprovements/playlists
Canadian I think, but their standards seem on par or higher than the US.
How is that zero carbon? That's actually higher carbon than the regular way with power tools.
Human power is very inefficient, you'll emit far more carbon because you'll need to eat more. And hand harvesting a tree is also far more wasteful of CO2.
for a 500 sq ft studio that works out to $30k.
Build a post-frame "barn" and get a massive space with no interior walls and get it for quite cheap.
In a 2000 sq foot house, a $2k tub costs a dollar a square. That's a significant part of the total price!
"Land of the free" doesn't mean the land is free of dickheads or immoral people who endanger others in their attempts to "get ahead".
And so laws are born...
Whether there are too many is totally a question though.
Why does adding a socket into a wall cost more than $50? Should be able to just open the wall panel, plug in an extra cable, close panel, done.
Adding a socket is the easy bit. It's the putting everything back to how it was that's hard.
If you want plain panelled walls you could install that now. And have your $50 socket. Most people probably don't like that tradeoff.
Of course, not everyone values the same things to the same degree, and a homeowner could cut a 4x8 piece of drywall into smaller pieces and have more easily removable panels like you're imagining.
what are you envisioning? using cheap consumer power cables inside of walls, and paying extra to have unused sockets hidden away inside of walls for years/decades, just so that it's fast to add an outlet?
we use screw terminals inside of the wall because they're cheaper and more reliable than the socketed connections. and we use heavy gauge cable with thick jackets for safety.
Secondly a minor addition, if there were a standard for junctions of power cables, so they could easily be added to, that would be nice.
Then installing a socket would be: open wall, connect socket you just bought with standard junction connectors, close wall. $50
Rather than: cut a load of holes in walls, connect socket using annoying wiring techniques, fill in holes you made, plaster and repaint so that next time it'll cost all that money again. >>>$50
If you want easily accessible utilities then there are ways to build to code where all of that is visible and accessible, it just won't be pretty. Aesthetics or utility, pick one.
Facit Homes, Wikihouse, and the Plywood Frame - https://news.ycombinator.com/item?id=27666320 - June 2021 (33 comments)
WikiHouse – Open source buildings and interiors for self-build - https://news.ycombinator.com/item?id=13856917 - March 2017 (53 comments)
The WikiHouse chassis system [pdf] - https://news.ycombinator.com/item?id=13029982 - Nov 2016 (1 comment)
WikiHouse's DIY kits are the open-source way to build a house - https://news.ycombinator.com/item?id=5768030 - May 2013 (3 comments)
SIPs are neat (https://www.sips.org/what-are-sips), but even they are an added cost.
Dirt-based construction is an intriguing idea, but generally you are trading materials cost (which is already relatively low) for quite a bit of labor cost.
A system that cheaply allows for enduring dirt-based construction would be an interesting advancement, but I'm not sure how universal that system would be.
We had looked into SIPs for our relatively fancy house, but budget won out. There are lots of neat building solutions that cost too much. If you think labor costs are high, wait til you try to find someone who will learn a new system.
Construction cost is not the reason that housing supply is tight—but engineers don't have as much fun fighting for better zoning policy.
https://www.opensourceecology.org/
There is just too much labor involved for the material savings unless you are in the third world.
Bagged earth construction is similarly cost effective given a cheap labor force.
In addition, in my area I would have to have my dirt amended because we have very sandy soil, but I don't know by how much because a few feet down that sandy soil turns to clay.
They have some mobile dirt brick factory machines, but those seem to be home-built prototypes for the most part.
you wouldn't mean clay brick, would you? I see some of the advantages, but want to be pendantic about calling a 10K old technology an 'advancement'
> WikiHouse is intended for buildings of up to 3 storeys. This covers 95% of all buildings, and allows gentle density neighbourhoods of up to around 75 dwellings per hectare.
> The main constraint on height is not gravity, but wind. In high winds, lightweight structures are more prone to slight lateral flexing, which is not allowed within most building codes. Further structural research and testing is ongoing.
---
[0]: https://seagatemasstimber.com/how-tall-are-tall-wood-buildin...
This can also be provided by sheet materials like plywood, securely attached, providing diagonal structure preventing racking of the frame.
In older houses, sheathed with one inch by eight or ten or twelve inch boards, diagonal wood bracing was cut into the two by four inch wall studs for diagonal bracing and structure.
https://theprepared.org/features-feed/segal-method
With many of these less common methods it's more work to show safety, code compliance, etc. For example the Segal method doesn't really allow for modern levels of air sealing and insulation.
On the contrary, I'd rather see more open designs for modern post-frame homes. They're lighter, cheaper, simpler, faster, and provide some design benefits. The only real downside is zoning needs to catch up.
Do you have any inductions on the cost of this building?
- carried on a truck - used while in place on the truck or is easily removed from it and then set up - which has an interface suited to a job site in terms of setting up a design and cutting
The Shapr3D seems to get some jobsite use, and there is at least one digital saw where one plugs in a dimension and the stop moves to the correct position for the cut --- the Yeti SmartBench seems like it might be a contender in this space, but still not seeing the CAD/CAM interface which would make it workable.
Really miss Saltire's SketchRight and FutureWave's SmartSketch for quick jobsite sketches.
The next phase for something like this--to bring more utility--is to make a CNC with an automatic feeder and ejector. That way you could put a stack of 4x8ft plywood in one side and get finished parts out the other end. Presumably at the speed at which a worker can take the finished part, install it, and come back for the next one.
The first use I'd imagine for something like that would be custom crown molding, drywall with electrical and plumbing holes pre-cut, perfectly-sized shims and frames for anything and everything, turning regular floor boards into snap-lock flooring, shelving and cabinetry, and other housing materials that could be made on-site if it were not for the complexity/detail.
One reason I can think of why they’re not used during regular carpentry/building a home is the time it takes to setup. It’s much faster to measure, mark, cut vs setting up a CNC equivalent.
A bit of search turns up this link: https://www.facit-homes.com/post/we-re-back-on-site-manufact...
Ahh but the maximum height is 14'! Well, on most roads and Federal highways anyway (plan your route!).
Also, the maximum trailer width is actually 12' with a realistic payload for non-flatbed of around 11'. The maximum width that'll fit in the bed in your typical American pickup truck is around 5-5.5'.
This seems to fix one of the big problems with pre-fab houses, that they are expensive to ship long distances, and therefore can’t benefit from economy-of-scale centralized manufacturing.
If 10% of houses switched to a single "system" with a small set of SKUs, such that everything is optmized for manufacturing, shipping and assembly - you could reduce the cost of construction significantly. This is basically an extension of the IKEA model for the house itself instead of just the furniture.
Took 4 people 6 days to build it. Slotted together like lego, it was quite something to watch.
Does this support mesh networking to extend the coverage?
[1]FreedConn:
https://www.researchgate.net/publication/339956316_The_lifec...
One obvious way to do that is to build one, or a few, giant centralized plants that pump out a zillion of these each year, i.e. economies of scale. Like Honda Civic cars or Lego blocks (which also are machined with tight tolerances).
Yes, I know that the founders want these to be manufactured in a decentralized way, all over the world, but that's not how economies of scale work. Systems that can be run decentralized (e.g. email, Bitcoin mining) often end up becoming centralized anyway.
In other words, stick construction has been public domain for so long that it would be impossible to even acknowledge its creator and significant contributors.
> And when the farmer has got his house, he may not be the richer but the poorer for it, and it be the house that has got him.
> It is possible to invent a house still more convenient and luxurious than we have, which yet all would admit that man could not afford to pay for. Shall we always study to obtain more of these things, and not sometimes to be content with less? Shall the respectable citizen thus gravely teach, by precept and example, the necessity of the young man’s providing a certain number of superfluous glow-shoes, and umbrellas, and empty guest chambers for empty guests, before he dies?
And the coup de grace, his own accounting of building his own house:
> The exact cost of my house, paying the usual price for such materials as I used, but not counting the work, all of which was done by myself, was as follows; and I give the details because very few are able to tell exactly what their houses cost, and fewer still, if any, the separate cost of the various materials which compose them:—
> Boards.......................... $ 8.03½, mostly shanty boards.
> Refuse shingles for roof sides,.. 4.00
> Laths,........................... 1.25
> Two second-hand windows with glass,................... 2.43
> One thousand old brick,.......... 4.00
> Two casks of lime,............... 2.40 That was high.
> Hair,............................ 0.31 More than I needed.
> Mantle-tree iron,................ 0.15
> Nails,........................... 3.90
> Hinges and screws,............... 0.14
> Latch,........................... 0.10
> Chalk,........................... 0.01
> Transportation,.................. 1.40 I carried a good part on my back.
> In all,..................... $28.12½
> These are all the materials excepting the timber stones and sand, which I claimed by squatter’s right. I have also a small wood-shed adjoining, made chiefly of the stuff which was left after building the house.
> I intend to build me a house which will surpass any on the main street in Concord in grandeur and luxury, as soon as it pleases me as much and will cost me no more than my present one.
I've heard the equivalent amount of hemp made into boards holds 60% more carbon than tree wood so perhaps that would be better, depending on the carbon required to convert the hemp to usable lumber.
>Is it firesafe?
>WikiHouse is not really any different from most kinds of 1-3 storey buildings with timber roof, floors, or internal walls, in that the building needs to be designed with adequate means of escape, and the chassis needs to be reasonably protected from catching fire. This can usually be achieved either with a plasterboard internal lining, by using a non-toxic fire protection coating, or by installing a basic sprinkler system.
>If you are building several adjacent houses, located close together in a row, you will usually need to use an external fire barrier material to prevent fire spreading from one building to the next.
https://www.wsj.com/articles/wooden-skyscrapers-are-on-the-r...
https://www.thinkwood.com/mass-timber
https://www.naturallywood.com/topics/mass-timber/
https://www.ijpr.org/housing/2022-09-04/oregons-mass-timber-...
And regarding fire retardation - Cross Laminated Timber Fire Testing from the Forest Products Laboratory and US Forest Service - https://youtu.be/HuVTCOmRGd0
As to the cost - https://www.fs.usda.gov/treesearch/pubs/62676
> Based on commercial construction cost data from the RSMeans database, a mass timber building design is estimated to have 26 percent higher front-end costs than its concrete alternative.
And from the paper:
> The resulting TLCCs of the two buildings under these scenarios are shown in Table 6 and Figure 5. From the results of these scenarios, it was found that the TLCC for the mass timber building would have a cost advantage with its longer life span (100 yr) than the concrete alternative (75 yr) when other factors are the same (see Scenario S0 and S4), and the higher front-end cost (value) showed an even greater advantage of 7.0 percent difference (Scenario S4). When the life spans of the two buildings were the same, the end-of-life cost or value of the mass timber building was not able to be offset by the higher front-end costs (see Scenario S1 [12%], S2 [6.7%], and S3 [5.9%]). In this case study, the two buildings were designed to be functionally equivalent. Thus, we assumed the same operational utility and maintenance during the building-use stage. No impact from these parts were considered in the TLCC calculations on the cost- performance for the comparison of the two buildings. But if there are energy savings discovered in the new mass timber buildings, the LCC analysis would reveal more cost benefits (Liang et al. 2019).
I can't find any sources that agree with your cost assessment... instead: https://www.bdcnetwork.com/5-myths-about-cross-laminated-tim...
> When considering the total in-place value of a CLT system, it is cost competitive to other plate building materials. But you also need to consider all the value added benefits:
> • More savings can be found in the reduced installation cost, usually 50% cheaper than installing other plate materials.
> • With an earlier project completion date, you are open for business sometimes months ahead of schedule.
> • The building structure will weigh less than half the weight of other construction types, so the foundation costs less money.
> • Job site safety is dramatically increased due to the prefabricated CLT panels and usually the only power tools are pneumatic drills.
> The intent of cross laminated timber is not to replace light-frame construction, but rather to offer a versatile, low-carbon, and cost-competitive wood-based solution that complements the existing light frame and heavy timber options while offering a suitable candidate for some applications that currently use concrete, masonry, and steel.
And the beam size gets into "don't design a concrete building and swap in mass timber". https://www.woodworks.org/resources/creating-efficient-struc...
Another aspect to the beams is that the structural elements are often left bare for aesthetics ( https://uploads.map-dynamics.com/0518_Structurlam-U.S.-Mass-... ).
Table 6 in https://www.structurlam.com/wp-content/uploads/2019/04/Struc... gets into the snow loads and I don't know enough engineering to be able to do a comparison between mass timber and other building approaches.
The main thing to consider is this isn't a "it costs 2x" or "it uses 2x more materials" because they are different materials with different designs. If comparisons are to be done, they should be done at the building level ("it cost X to make a N story building with M square feet per floor" and "building A had a sustainability rating of P while building B was rated at Q with a difference in cost of Z%").
Yes, trees remove carbon, but now you've just cut them down and released a bunch of carbon in that process (plus all the CO2 you emit, you know, building the actual house).
Edit: Ok, looking more through their website I came across this: https://www.wikihouse.cc/product They say that the upfront carbon cost of building a WikiHouse is - 17T CO2, compared to a normal house of + 30T CO2. This is so fucking misleading, I've just lost all respect for the makers of this. I think it's a great project, but once you start bullshitting like this, you can get the hell out.
The carbon from the trees is now not in the atmosphere, it's in the wood components, and won't be in the atmosphere until the wood components reach end of life and are burned/rotted/whatever.
So yes, carbon has been removed from the atmosphere. I don't understand the objection.
If X amount of carbon was in the trees, X amount of carbon is now in the building materials (at best). There's no further removal of carbon from the atmosphere by this alone. And all of the future carbon the trees would have sequestered is now not going to be sequestered by those trees. So more likely carbon positive than negative.
> The space the trees were in will now have more trees grown in them.
That's an assumption. And even if it were true, those trees would take years to begin to sequester the same amount of carbon that the previously existing trees did. And even then, it's not obvious that those new trees would sequester more carbon than the previous trees would have had they been allowed to continue growing.
Plus if you're going to say that building with blocks is carbon negative, you're going to have to talk about how those trees get turned into blocks, and how the overall process including that, is somehow carbon negative.
It sounds like you might be making a stock vs flow error here. Or I could be misunderstanding you.
> And even then, it's not obvious that those new trees would sequester more carbon than the previous trees would have had they been allowed to continue growing.
1. Trees slow as they grow (after a certain point).
2. Commercial tree farms exist to grow trees. If they weren't growing trees for consumption, something else would be done with that land.
Yes, for example let the natural vegetation take over, increase biodiversity, and sequester more carbon thanks to the increased biodiversity and better soil than fucking tree farms.
- A lot of the time plantations are planted on less productive farmland. - Not all plantations will naturally regenerate quickly back to native vegetation.
- Those trees were planted for a reason and a lot of plantations are planted on degraded farmland or scrubland.
It's a very safe assumption
And we’re already doing this for centuries - using wood for making buildings - so we’re merely continuing the status quo, not magically putting more carbon away suddenly.
You're ignoring material waste. This process doesn't consume 100% of the tree; only a portion of the tree's carbon is sequestered into the building. The rest is rotting.
> The space the trees were in will now have more trees grown in them.
Trees are renewable, but it's not quite "copy&paste". Further, the harvesting of the trees was certain to be carbon intensive.
So, on the whole, you can trust this process IS NOT CARBON NEGATIVE.
What it may be is LESS CARBON INTENSIVE than a traditional process. They are VERY FAR from crossing the neutral line and yet are trying to claim carbon negative? That's pretty brash.
Does the objection make more sense now?
> You're ignoring material waste. This process doesn't consume 100% of the tree; only a portion of the tree's carbon is sequestered into the building. The rest is rotting.
It's ply. Apart from the root system, it's quite close to 100% indeed.
> Trees are renewable, but it's not quite "copy&paste". Further, the harvesting of the trees was certain to be carbon intensive.
Tree harvesting is pretty much fine. Transport is what pollutes the most here. The new growing trees are carbon sinks. It's not a question of renewability. It's just that you used to have CO2 in the air and now it's a house. Processing will mostly use electricity so it depends of how your local electricity is produced of course.
> They are VERY FAR from crossing the neutral line
They are probably not very far. It's not an heavily mechanised project. Assembly is mostly done by hand. Considering the amount they sequester, being neutral is not that far fetched.
I disagree on your accounting (largely because the house is torn down one day and further a CNC throws wood dust everywhere and this project requires one front and center), but none of that matters. Carbon negative is a strong claim that requires strong evidence. Of which, none has been offered.
Is it, though? Because operations I've been to use every last available ounce of the tree. Trunk and limbs are sawn, small limbs, branches, bark, and offcuts are ground for biomass heating. Yes, it's burnt, but releasing no more carbon than it captured in its lifecycle and to provide a tangible end result that would otherwise be achieved with fossil fuels.
Root stumps rot, yes, but providing a breeding ground for insects and hence birds and small mammals and hence predators. They also fix soil beneficial bacteria and fungi, and having spent all their energy breaking up the soil and then breaking down they prepare the best soil bed for the new tree to take its place and sequester more carbon.
It's not the perfect process, by any means, but wood as a building material is infinitely more sustainable than concrete, gypsum and stone.
Cool, show me the part where any of that means this company has a right to claim carbon negative?
Onus isn't on me here.
I just pointed out that your emotional response that backs your argument isn't necessarily reflective of what actually happens.
But I mean, if we want anything to be carbon negative we need to capture carbon from the atmosphere and put it somewhere; e.g. reclaiming land for forests or putting carbon back into the ground where we got it from, but putting carbon in constructions as part of the solution, why not? For dealing with climate change, the important part is getting it out of the atmosphere.
I'm not sure what "upfront" means here, but it makes sense if talking about overall net CO2 usage. The amount of CO2 in the atmosphere after building would be 17T less than before the tree started growing. Ie the tree absorbs 17T more during its growth than is emitted during harvesting, transport and construction. Whereas an equivalent brick building puts 30T more into the atmosphere than the (unharvested) tree absorbs.
1) The wood the house is built with will not be there forever, some day the house will be torn down and the wood burned or rotten
2) Cutting down trees and planting new ones is not a good way of carbon sequestration. Otherwise, why not cut down all trees and just plant new ones? Bam, carbon negative, climate problem solved.
People need to understand that trees should not be seen as a renewable resource in the context of climate change. Not for building, not for burning as fuel.
Another thing worth considering is that building small houses uses a lot of land, land which might have had forests. That needs to be considered too.
This carbon negative claim taken to the extreme would mean, that we should just cut down all trees and plant new ones. I think you can see why this is ridiculous?
Another wood-house project created by civil engineering or building material science graduates (Leeds Beckett University)--similar to the last one.
Build costs similar to brick (ouch!), requires a specific CNC operator to build panels (supply chain ouch!), and creates an integrated house (ouch! to any renovations using conventional materials; ouch! to system longevity).
I hate these as they're basically the results of a couple of graduate students operating under a innovation grant.
The practical results of this are that someone is going to find a local CNC operator (within 320km based on the study), find out the costs of buying 300 sheets of quality 7-layer plywood and running a custom project with the CNC operator, find a local engineer willing to sign off on the project (for insurance, mortgage, and to maintain the 10 year defect free period), and then have to find a local labour contractor willing to use their building materials as the structure.
After all that legwork, they're going to go with a traditional building contractor.
Unsure what this means. The CNC files are open source, and there are millions of CNC machines in the world. What specific CNC operator?
In general, I'd say your comments are valid for a random homeowner that decides they want to try this out. If you think in terms of a contractor who wanted to start specializing in this in their region, it seems quite doable. They could have their own engineer that has seen many of these, and a stable source of plywood/OSB and access to a CNC shop.
The specialized manufacturing requirements for modules makes sourcing materials from traditional suppliers functionally impossible, adds additional (highly specialized) manufacturing overhead, and drives up the cost of materials.
The wildly non-standard construction methods mean subcontractors will have to train on using the system, and projects will start from a functional zero-prior-experience knowledge base, which invites a diversity of headaches and potential safety issues.
On an unrelated note, insurers are likely to be deeply skeptical of unproven construction methods in general, and plywood-heavy construction methods in particular given their propensity to fail catastrophically from even relatively minor moisture-related insults. Insurance premiums are likely to reflect that.
Folks love to knock on traditional “stick built” buildings. I don’t get it. I live in a frame house built in 1927. It’s not going anywhere so long as the owners are stewards of the property.
Watching similar houses get built, it’s a fairly efficient process. I don’t think the costs of homes are really driven by framing.
Super conservative code requirements like electric socket requirements (my kitchen remodel required the addition of *5 dedicated circuits with arc fault breakers in most cases), fire sprinklers, etc and others drive costs.
A frame house with a thoughtful architecture that incorporates passive heating/cooling, etc will cost less, be easier to bike and require less fiddling.
I really liked the idea and team but (at least at the time) it was still very new.
Too much risk to take on for individual homeowner and it was cheaper for me to get a local contractor who had experience in developing what I was after.
P.S. The concrete foundations look far from zero-carbon.
The main strike against suburban lifestyles today is that they’re energy intensive and thus carbon-heavy. There is nothing wrong with a energy intensive suburban life if that energy is carbon neutral.
(And yes, as other posters point out, there are some additional environmental externalities associated with suburban versus urban lifestyles. It’s not clear to me how severe these externalities are, and thus whether they are worth the tradeoff of increased quality of life for the many people who love living in the suburbs. As an extreme example, living a pre-industrial lifestyle would be much more environmentally friendly, but it isn’t remotely worth the quality of life tradeoff.)
Also note that, due to much heavier weight of electric cars, asphalt concrete surfaces will be damaged a lot faster. The relationship between vehicle weight and its damage to the road surface is exponential, not linear.
Sure, convenient for individuals but absolutely not sustainable for society, nor the planet. Even with electric cars and green energy.
The insane cost of cars: https://m.youtube.com/watch?v=ztHZj6QNlkM
The hard truth is that if we don't want to abandon our comfortable modern lifestyles, 80-90% of us will have to live in dense cities and use mass transportation 95% of the time.
People also don't have to live in what we think of as cities at all. Rural living is fine if people live closer together in those areas. Such that they live in walkable towns that don't require driving and can be easily connected to other towns and cities via a bus or train. Europe is much better at this but you see vestiges in New England. It's just nobody should really be living beyond walking or biking distance of core services (transport, shopping, etc). The benefit for those who love nature is more untampered natural beauty in the surrounding areas. If anyone has ever been to a place like Banff it's lovely when fine right.
We don't even need more than that on average, we don't need Hong Kongs everywhere. "Brownstones" will do :-)
A home with space and a nice sized yard and an automobile to travel around in is great. It's nice to have a local train too to get into the adjacent metropolis, etc.
I have three kids. The eldest is 15. I’ve never owned a car. I probably never will.
For short stuff, bakfiets. For the second part, sure, why not? Get a baby buggy for multiple kids.
Walking is also good for you.
Also, is all of this happening as a single parent? How many single parents with 3 kids are even out there? 0.00001% of the population?
All these problems are solvable. With probably less than half the money spent on car infrastructure and 5% the pollution.
Why does it matter how many parents? One could be away or working and the other has to go 5 miles to Costco or whatever. Your little bike things don’t work. Also there are lots of single parents with 3+ kids.
I don’t want your terrible solution or way of life. I like having a large home with a large lawn and a large SUV to drive my family where we want when we want. I take trains and walk too and use strollers of course. But that’s like 20% of the time. Your comment reads like a person who doesn’t have kids.
It's impossible to service low density housing efficiently.
The Strong Towns ideology is attractive (especially for northern US cities), but I think if self driving cars come into existence, the ideas might not get very far in most places. Self driving cars are going to encourage sprawl like no other force ever has. I know I'd move further out if I had a self-driving car.
Just look at NYC to find the typical pattern: Young person lives with multiple people in an area like the Lower East Side or Williamsburg (yay social life!), then begins to settle down in a place like Park Slope (just married!) and has a kid (dedicated to urban living) and then another kid comes along and/or the reality of urban living (the schools are awful, it's cramped and expensive, the city offers you nearly nothing since you don't go out like you used to) and the brownstone is sold for a tidy profit and they're off to the NYC suburbs to get more space and a better quality of life to raise a family in. The city is a short commute away still.
I mean sure, if you live somewhere without building codes, don't need a foundation, and don't care how long something lasts or how safe it is. Just chuck it together. Just some 2x4s and plywood is all you need for a treehouse. Maybe.
Stick framing is cheap and simple- 2x4s are abundant. And you can do it yourself solo with minimal tools.
Also, using plywood is way more prone to water issues than solid wood.
I wouldn't build most houses today out of 2x4s, simply because its not a big enough insulation cavity for a modern home. Stick framing being cheap does not substitute for planning. As you say - you need to design a structure and that includes hiring an engineer for more than just 'passing codes/inspection' but also for structural design of your home.
It's unlikely you'll be able to design a roof out of 2x4s without making major sacrifices to the design of the house, and you're probably not qualified to judge the worst case loading in your area or capacity of a 2x4 roof (or else you wouldn't even mention 2x4s).
The linked site includes several guides including an engineering guide most non engineers would struggle to understand. https://www.wikihouse.cc/guides
Plywood is not particularly prone to water issues, and isn't used in the same way as solid wood would be. In situations where plywood would be having water issues, so would solid wood. You might be confusing plywood and OSB. Structurally, plywood sheathing is primarily used for shear capacity to let structures handle lateral (sideways) loads to resist racking, and to have somewhere to attach the exterior materials of the structure to.
The linked engineering guide provides structural testing numbers of their panels for various capacities that a structural engineer understands. Like proper stick framing, it requires planning and design, rather than grabbing some 2x4s and letting er rip.
I’m happy to see this project and would like to see more like it, even if this is not quite ready for show time. The possibility of using advances in technology and open source methods to allow people to make more stuff for themselves and their communities in a way that is efficient and feasible is exciting to me.
(It also, in general, makes humans feel good to make and then use something).
And does it solve it at a price point that makes it practical in comparison to other high efficiency house building technologies?
Perhaps when compared to this CAD/CNC approach. In the traditional stick-built house you need wood and other materials, tools of all sorts, and specialized workers who know the steps in order. If some critical material hasn't been delivered yet, workers have to pivot to a different task or simply stop working.
With this other method, 100% of the material is cut/delivered to the site, and the workers need only to follow the instructions. Their tools are fewer, too—hammers, nails, hand-crank lift.
In the future, anyone who likes putting together IKEA furniture may consider an exciting new career in home construction. I say that half in jest, half in hope.
Framing, cladding, and insulating a structure, which is all that is represented here, are the simplest, least tool-intensive tasks involved. Additionally this style of construction can seamlessly cope when a foundation is poured a couple inches out of dimension or a few degrees off square. By comparison I shudder to think what flavor of chaos would kick off on a DIY Ikea house project when the assembly team has to cope with similar issues with only pre-fab components to draw from.
Standard building methods expect all of the material for each phase of construction to be trucked in in one bundle, identical to a pre-fabbed system, but with the added benefit that if any material is found to be sub-standard, or if there are errors with the delivery materials to make up the difference can be trivially sourced from any lumber yard or big box home improvement store.
Long story short, framing a house isn't particularly complicated. Folks that are intimidated by the process don't have enough experience in the industry to know first-hand that there isn't a single task involved that isn't routinely completed by individuals who have little prior experience, are high out of their mind, or both.