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Wasp 3D-prints eco-homes from local raw earth for $1K

The building code wouldn't know what to do with 3d printing. You might suggest using IBC Section 104.11 but I suggest that most building departments do not have the technical expertise to evaluate such proposals. In addition 104.11 was intended for one off exceptions. If you used 104.11 to justify a generic solution the building official would have in effect modified the building code, a power he does not have. The problem is that in our system of laws adoption and modification of laws, including building codes, must be adopted by a properly empowered legislative body.

While 3 D printing is intriguing more research is needed to understand how it can be used. A major concern is that 3D printed concrete typically does not have reinforcing bars. For example, this could create real problems if the structure is subjected to earthquakes or uneven ground settlement. I suspect that we would need other tests to sample the concrete to verify concrete strength.

Injecting soil and local materials in the concrete is a real concern since it will not perform the same was as traditional concrete.

The end result is that it is questionable whether a building official has either the technical expertise or legal authority to permit a structure using 3D printing of a structure using soil from the site.
 
Mark K said:
The building code wouldn't know what to do with 3d printing. You might suggest using IBC Section 104.11 but I suggest that most building departments do not have the technical expertise to evaluate such proposals. In addition 104.11 was intended for one off exceptions. If you used 104.11 to justify a generic solution the building official would have in effect modified the building code, a power he does not have. The problem is that in our system of laws adoption and modification of laws, including building codes, must be adopted by a properly empowered legislative body.

While 3 D printing is intriguing more research is needed to understand how it can be used. A major concern is that 3D printed concrete typically does not have reinforcing bars. For example, this could create real problems if the structure is subjected to earthquakes or uneven ground settlement. I suspect that we would need other tests to sample the concrete to verify concrete strength.

Injecting soil and local materials in the concrete is a real concern since it will not perform the same was as traditional concrete.

The end result is that it is questionable whether a building official has either the technical expertise or legal authority to permit a structure using 3D printing of a structure using soil from the site.
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I am rather confident that since this is all R&D, there is certainly a level of engineering involved as they continue to develop this technology and figure out the best use for these types of structures. In my humble opinion, this is a long way off from the point where it can be used as a functional, occupied building, even if an R3, for example. It appears to have a concrete foundation in place. Technology has to start somewhere. Concerning the building code, I am not sure this would even qualify under alternative methods and materials at this point due to so many other factors not being addressed. I am sure that by the time this is ready for commercial use, there will be an army of engineers performing calculations and testing.

If there is no prescriptive method already in place, you are right, it is questionable whether a building official has the technical expertise to permit a structure such as this. At the same time, I am also confident that there are no engineers that have the technical expertise and tools available to design solely based on structural calculations. This, like many construction-related areas, would be beyond the scope and limits of engineering and in the realm of testing. We all have our limits.
 
The advantage is that the material is sustainable and already at the site. The disadvantage is the material. Such a structure could be suitable for uses other than habitable structures such as horse stables and chicken coops but the expense is most likely way more than conventional construction and takes a long time.
 
To say "that there are no engineers that have the technical expertise and tools available to design solely based on structural calculations." ignores some realities.

First engineers do not design solely based on structural calculations. Calculations are a useful tool that inform the engineers understanding of the characteristics of the materials and elements involved. There are many engineers that would demand the test results and previous efforts. In addition, the design is informed by a number of other configurations.

Testing does not exist separate from engineering. In fact test results and their use is central to the practice of engineering. Inspections and testing are basic engineering activities

Yes there are engineers that practice outside of their area of expertise, but it is inappropriate to judge all engineers based on these individuals.

There is a difference between proscriptive provisions such as those included in the IRC and provisions which exist in the IBC that provide a methodology with limits that allow the engineer to select a solution that will provide acceptable performance. These more general provisions are not considered proscriptive. It is these more general provisions that allow an engineer to produce designs that would not be allowed by proscriptive codes.
 
I could not find an example of rebar in printed concrete but the discussion suggested that plumbing and electrical need to be surface mounted rather than cast in the concrete. This would suggest that there is a problem with 3D printing a concrete structure with reinforcing. There was a video of 3D printing of a building but I saw no vertical reinforcing. in the video. These buildings will have difficulty resisting earthquake loads.

Without reinforcing I do not believe that you can satisfy the criteria of Section 104.11

Trying to 3D print the reinforcement opens up another group of questions regarding the steel properties.

The standards used to design concrete structures are typically ACI (American Concrete Institute) standards. Now we are supposed to accept a UL standard to replace the ACI standards. There is a credibility problem. UL has credibility when it comes to electrical safety but I suggest that this does not transfer to concrete design.

Remember UL was paid by the proponents of 3D printing of concrete to develop this standard and as such there will be a bias.

When they talked about building codes it was clear that they were using Section 104.11 but as I noted that section was intended to apply to truly special cases. What they are proposing is that if a building complies with the UL standard that code compliance is assumed and that you could build as many buildings as you want using this technology. Effectively this is the same as modifying the building code without having the legislative body approve the standard.
 
The first post I made was after just a few minutes of the video where the content was the simple structure. I just watched the entire video and I must say, I am impressed. The amount of discovery these folks have made with 3D printing is substantial. New materials and new uses for established materials are the focus of a brilliant team. The versatility of 3D printing lends itself to the whims of imagination as no other form of construction can.

If the constraints of structural engineering can be met there is a future for this technology. Given what has been achieved to date, that will happen.
 
"Printed" concrete and mud seems little different than adobe construction, which has served well. Was interesting but not surprising to Google adobe and find it's major disadvantage is the difficulty of obtaing building permits. It's a problem if no special interest (bias) who benefit from this type of construction.
 
To say that everybody is biased in one way or another ignores the fact that most structural standards are not directly funded by the special interests and the standards bodies make an effort to involve a diversity of viewpoints. If the 3D printing advocates have the guts, they should propose that ACI address 3D printing. If this is done, I suggest that some changes will need to be made to the technology and the end result will limit where 3D printing can be used.

The concrete codes have been developed with the recognition that reinforcing is needed to compensate for the fact that concrete is weak in tension. Without the reinforcing you have problems.

Mention was made to adobe which is essentially a form of masonry. It is well recognized that adobe structures are particularly likely to be damaged in earthquakes. Because of the poor performance of unreinforced masonry buildings, it is now necessary in California to retrofit such buildings.

So now UL is saying that concrete without reinforcing is just as good as concrete with reinforcing. I suggest that UL has a credibility problem.
 
I've watched the AISI and PCA and the wood organization and other reps at code committees and hearings and respectfully disagree with "ignores the fact that most structural standards are not directly funded by the special interests". None of them want less expensive materials with less high cost laborers required permitted.

And thank heavens we don't all live in California nor all in seismic zones, and because we don't, shouldn't be held to those same standards. There are adobe structures that have lasted lifetimes.
 
jar546 said:
Still in its infancy with technology improving while in R&D, this looks promising in the right climate. Very interesting.

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What remains unanswered is, who will buy them and secondly will builders invest in the printer that will do the job? Maybe the builder gets cut out of the loop and using GPS, the structure is printed from the design firms office. Also left unaddressed are Specialty Codes and their application. I think it is important to keep in mind that these printers print horizontally which makes them kind of a "one trick pony". Get back to me when printers can printed metal{s}. There may be some application here, however it appears there are severe limitations in the residential arena.
 
Very interesting thank you for sharing. My question too is more on structural integrity, then fire resistance, then insulating qaulities. The science of concrete is thousands of years old. It has a long track record for predictable reliability, use, and history. I like concrete.
 
Well Jar if they did that in South Florida the "lake" they created would become an instant mosquito breeding ground. Also the "lake" will be classified as a wetland (did you notice the cattails) by some, if not all local, state or federal agencies.:D

Only time and the free market will determine if this takes off in developed nations
 
local12.com

Woman moves into first 3D-printed Habitat for Humanity house in US

WILLIAMSBURG, Va. (WTKR/CBS Newspath) - On the first day of winter, a Williamsburg woman officially took ownership of her new home: the first-ever completed 3D printed house in the U. S. made by Habitat for Humanity. Crews broke ground in July on the 1,200 square foot, three-bedroom house, and...
local12.com local12.com

www.cnn.com

World's largest 3D-printed neighborhood to break ground in Texas

Scheduled to break ground next year, the project will see 100 single-story houses "printed" on-site using advanced robotic construction.
www.cnn.com www.cnn.com

There’s are a handful of examples out there in the United States.
 
mtlogcabin said:
Well Jar if they did that in South Florida the "lake" they created would become an instant mosquito breeding ground. Also the "lake" will be classified as a wetland (did you notice the cattails) by some, if not all local, state or federal agencies.:D

Only time and the free market will determine if this takes off in developed nations
Click to expand...
That's why you add fish, preferably invasive Tilapia or something equally problematic. Mosquito eats you, fish east mosquito, you eat fish. Sounds like the circle of life right?
 
I saw an article on the Williamsburg house, and it had wood studs inside the 3-D printed concrete walls so it could be wired. I'm not sure there would be a significant cost savings until somebody develops a way to put in electrical boxes and conduit as the walls are printed, so they can be left exposed.
 
The statement that a building survived a 7.4 earthquake is not very comforting since a building 50 miles from the epicenter is subjected to much smaller forces than one right next to the epicenter. Even if we can suspend belief and assume that a particular building can provide equivalent safety how do we know what variations can be accommodated before such an assumption is no longer justified. Antidotal evidence is not sufficient.

Without sufficient technical data I do not see how we can reconcile an assumption that the process produces safe code compliant buildings when for example unreinforced concrete is not accepted.

Years ago, I briefly looked at the use of soil mixed with concrete and became aware that the material properties were subject to significant variation. Given the natural variation in earth materials I do not see how you can extrapolate safety of one building constructed of earthen materials from another "similar" building.

Bottom line: I do not believe there is sufficient evidence for a building official to justify the permitting of a building constructed using 3D printed earthen materials.
 
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