Status of 3-D Printing for Single Family Dwellings

[surfer08]

Seeking general information and thoughts about my hopefully good idea. I plan to develop 3 Florida residential properties using 3-D printing. The 3-D concept is very interesting. My plan is making an architectural and engineering 'statement' while developing the know-how for future projects. FYI I am a licensed architect in the State of Florida and California frequently working with difficult problems, codes, engineering, jurisdictions.
Thanks in advance for your thoughts.

 

[MotorCity]

It seems to me that 3D printing structures poses more of a constructability issue that a design issue, the major difference being of course the method in which the concrete is placed. Its definitely a newer concept but certainly not unprecedented. I see two major players that should be consulted before attempting this: the AHJ and the contractor(s). I'd talk to the AHJ to see if there are any special local requirements for this type of construction that they would like to see during a plan review. My guess is that you will get the deer in headlights look from them because they probably have not dealt with this before. Regarding contractor's, I'd talk to contractors that do this type of work and get their input on the design. In my neck of the woods, I imagine they are few and far between and I would not even know where to begin finding a contractor that does this. Also talk to subcontractors. Since the walls are concrete, how are they insulated? how are interior and exterior finishes attached given the irregular (i.e. not flat) wall finishes I've seen? Are utilities run in the wall or on the wall surface?

 

[kipfoot]

The printed houses seem to be pushed as a low cost method of the future, while relying on subsidies in the name of research. I like the organic feel of the layered surface, and think you could do some interesting things by introducing curves in the plan. It would be interesting to know if you can make it economically viable.

I'd say to make a call to these guys: Alquist who were involved in a project near me. project link

 

[Brad805]

I would look at some of the case studies in the Netherlands. Personally, I am not sure how viable this is nor do I see how much of a savings this is. In most common homes the structure is less than 30% of the project cost. If I save 5%, yipee? These machines will not like rebar except for horizontal bars either, so it could be tricky in some parts of CA.

 

[CrabbyT]

Structurally, the first thought that comes to mind is that the design wind speed in some parts of Florida is very high, and I would be curious how the walls would be reinforced. I don't like the idea of using post-tensioned cables; someone might drill into one and get cut in half while trying to hang a picture or something.

Philosophically, my hope is that these houses will eventually prove to be pretty cheap to make, and that as a society we can end homelessness. My concern is that these houses will eventually prove to be pretty cheap, and homelessness could increase as developers use house printing robots to cut out skilled laborers while maintaining the same price point on their structures as what they would for conventional houses.

 

[MotorCity]

I'm just waiting for an ambitious DIY'er on Youtube to give this a shot and see a bunch of cringe worthy video clips.

 

[canwesteng]

We could end homelessness now if we wanted to - homelessness was largely non existent in the soviet union and they were much poorer than we are now. The solution is slightly cheaper houses though, it's zoning, social housing, supports to help people get employed, addictions treatment... and so on

 

[GC_Hopi]

Here is another firm that has built a 3D Home. The technology seems limited to wall and 1 story structures. Foundation and roof is done with traditional construction.

 

[CrabbyT]

The solution is slightly cheaper houses though, it's zoning, social housing, supports to help people get employed, addictions treatment... and so on

Did you mean "the solution isn't"?

I'll tread lightly, because we're dangerously close to talking politics, and it's nots polite to talks politics on the engineering forum, plus I don't want to hijack the thread. I agree with you that housing alone wouldn't fix all the societal issues at hand. But I wasn't talking about slightly cheaper. I'm talking about... what if houses cost less than $10,000?

I guess what I really meant was, no one currently wants to foot the entire bill to create shelters for the homeless. At the current prices, it's untenable. Here's my math.

[ul]
[li]Cheapest home in my area according to Zillow is about $75,000.[/li]
[li]Approximately 552,830 homeless people in the USA[/li]
[li]Approximately 60% of homeless people are kids[/li]
[li]Assume 20% of homeless people are adults who would buy a house.[/li]
[/ul]

0.2 × 552830 × 75000 = $8,292,450,000

Now, consider that Icon is trying to produce 600 - 800 sq ft houses that cost $4,000 to build (source:

https://www.dwell.com/article/icon-3d-printed-homes-for-4000-dollars-23d715bf).

0.5 × 552830 × 4000 = $442,264,000, or about 5x cheaper than a THAAD missile defense system. That's a much more palatable cost. Maybe we could all collectively agree to just donate whatever money we've thrown at the lottery and put it in an escrow account to be used as the need arises.

 

[phamENG]

That was a $4,000 house...in 2017. Today, the wood in the roof will cost as much. I take you're point, though, and tend to agree.

As for the 3D printing and reinforcing, I had the idea several years ago to go for a PhD to try to develop a method akin to masonry design for 3D printed houses. I might be giving away the farm here with some amazing business idea (somebody else probably patented it a decade ago), but I don't have time for that:

If you look at a lot of 3D printed houses, they use curves and internal stiffeners within the wall. This works great for small, single story houses in low wind and low seismic areas. What if you develop a pattern that gives you 'cells' like you have in a CMU building? (My first thoughts were interlocking tear drop shapes.) Then you can build the wall with cleanouts, drop in the bars, and grout using high lift grouting techniques. If you want to go multistory, use a large cleanout at the second floor where you can get access and install a mechanical coupler or weld the bars.

 

[driftLimiter]

Here is a good article with some references to historical and current practices in this field.

Link