♪♪ Kevin: On "Ask This Old House," our experts travel across the country to answer questions about your house.

♪♪ Today, Ross heads to Austin to visit a company that is 3-D-printing homes.

Ross: It almost looks like soft serve coming out.

That is cool.

Kevin: Then we meet a landscaper who is passionate about making Detroit grow and flourish.

And Tom shows us how to turn a square bowl... ♪♪ ...coming up next on "Ask This Old House."

♪♪ Ross: We're here in Austin, Texas, a city known for innovation and one of the fastest growing tech hubs in the country.

And there's one company that's reimagining how we design and build homes.

Alright.

You must be Conner.

Conner: Ross.

Ross: Yeah.

How's it going?

Conner: Good to meet you, man.

Ross: Nice to meet you as well.

Conner: Yeah, absolutely.

Ross: What are we looking at here?

This is crazy.

Conner: Welcome to Austin, Texas, where we're 3-D-printing homes in the wild, man.

Ross: Wow.

Conner: This floor plan in particular is over 4,000 square feet.

It's 4-bed, 3 1/2-bath, single story.

I think all the things that consumers typically want with some additional stuff that we think they'll value over time.

Ross: Yeah.

For sure.

So take me through the wall assembly.

Conner: Yeah, absolutely.

So you're looking at a 12-inch-wide wall kind of from out to out.

So we have a bead on the interior of the home, a bead on the outside with a cavity in the middle.

Ross: Okay.

Conner: While we're printing, we cut in openings for outlets and switches.

You're seeing behind me an opening for plumbing as well.

Ross: Yeah.

Conner: So that by the time you're done printing the wall system, all your openings for plumbing and electrical are where they need to be, and that saves time for the plumbers and electricians.

Ross: Right, but there's no studs in the way, so you can rough in all that MEP from above and drop it in.

Conner: That's right.

Ross: That's clever.

Conner: We install the roof, run all that stuff above and drop it in.

Ross: Got it, got it.

Conner: Once we roughen the home, we blow in open-cell foam.

It's moisture-resistant, mold-resistant, kind of meant for a masonry application.

And that gives us our high R-value that we end up with in our homes.

Ross: Got it, got it.

I mean, I'm looking at a masonry wall and, like, CMU block typically has reinforcement.

I saw some rebar here on the floor.

Conner: That's it.

Ross: So I assume you're doing the same thing?

Conner: Yeah.

Similar principles.

So we install reinforcement along the beads, across the bead so that it's all tied together.

And then after we print the wall we drop it in vertically.

Ross: Got it.

Conner: Yeah.

Ross: So it gives you a structural integrity.

Conner: That's it.

Ross: Make sure it's shear.

Conner: Yeah.

So a lot of those same principles of CMU.

Now, Ross, I do want to call out that it's similar in some ways but pretty different in some ways.

Right?

Ross: Yeah.

Conner: When we're done printing the wall, you don't just have the framing of the walls, but you have multiple layers.

So typically you'd frame, you'd have sheathing, a water barrier, you'd have your cladding on the outside, drywall on the inside, and tape, float, texture.

Right?

I just rattled off like five or six different things.

Ross: Yeah.

Conner: When we're done printing, you have it all in one.

So it's reducing the number of people kind of in and out.

So confusion and clashes.

It also simplifies the supply chain.

Ross: I can see that for sure.

I mean, your double-pass design represents a lot of different layers in the assembly.

Conner: Yep.

So really simplifying things.

Yep.

Ross: That is cool.

Now, as far as how long this should last, you know, resiliency, talk to me about that.

Conner: That's something that we take a lot of pride in.

So in the short-term kind of construction picture, we hope to bring down cost and time.

But there's a lot of long-term value here.

It stands up well to flooding.

Termites don't want to eat concrete.

And then even things like fire, right?

We think about California.

It stands up well to fire.

Ross: Yeah.

So the cement is being poured.

Conner: Yep.

We're mixing the dry powder in our material delivery system and then extruding it one layer at a time.

You're seeing it stay fluid enough to kind of get through the hose, but it's standing up on its own.

By the time the printer gets back here, it'll be stiff enough to hold itself up.

Ross: It almost looks like soft serve coming out, you know, making for an ice cream or something.

Conner: Some may say.

Ross: Yeah.

Conner: Some may say.

Ross: That is crazy.

Conner: Yep.

Ross: Okay, so now I see what you're talking about with the two-layer pass here.

Conner: Yep.

Ross: So each one, you're saying one inch by two and a half?

Conner: By two and a half inches, that's it.

Ross: Got it.

And what's going on with these right here, these channels?

Conner: Yeah.

You're looking at a core that we print really intentionally.

We place these where we need them by windows and doors and kind of throughout the wall system.

We use this as a cavity to bring strength to our wall system.

So we'll drop in a vertical stick of rebar and then we'll grout it.

Ross: Got it, got it.

So that will literally be a grouted column all the way up with rebar for reinforcement and stability?

Conner: That's it.

Ross: Got it.

Whoa.

Watch your head there.

Conner: Yeah.

Watch out.

Coming your way.

Ross: This thing's sneaking up on you.

Conner: That's right.

Ross: I know.

That is cool.

That is really cool.

Now, what about hanging a picture on the wall when it's all said and done?

What are you doing there?

Conner: I'm glad you asked, Ross.

That's our number-one question.

Really simple.

We get a masonry bit, drill into the wall, put in an anchor, put in a screw, and then hang whatever you need to hang.

Ross: Nice.

So this printing process, I can see it happening pretty fast here.

Like, how long does it take to actually 3-D-print a home?

Conner: We'll stack anywhere from a foot to a couple of feet in a given day.

So you can imagine a 10-foot wall taking about, 10 days, 7, you know, a couple of weeks.

It kind of depends on the size of the house, but we'll mobilize in a couple of days, get to printing, and then get out of here all within about two weeks.

Ross: Awesome.

Conner, this is really cool stuff, but I'd love to see a finished product.

Conner: I'd be happy to take you to one.

Ross: Really?

Conner: Yeah.

Ross: Look at the house there.

Conner: Ross, welcome to House Zero, one of our houses in the wild.

Ross: Wow, it is cool to see the finished product here.

Conner: Yeah, absolutely.

Ross: Look at that.

Floor-to-ceiling windows coming down, the curvature.

Beautiful.

Conner: Yeah.

Thanks, man.

We were excited to bring floor-to-ceiling windows to this home and have carried into designs like you saw on the slab today.

Ross: Yeah.

So I mean, obviously floor-to-ceiling windows.

Great.

Obviously got to get the architecture details right.

The flashing details, the air-tight details right.

So that looks like a little bit of a challenge where you have the mixture of two.

Conner: That's right.

One challenge of of our technology is a lot of curves with the wall but often straight materials.

We love letting those straight materials kind of float out past the beads.

And we'll do a lot of our weatherproofing kind of back in the cavity.

Ross: Nice, nice.

And then of course the shape, you know, it just -- it looks really cool.

And typical builders that we work with, curves, that's cost and that's complexity.

Conner: Something we're really excited about with our technology is bringing a lot of architectural freedom to designers in the world right now.

And the feedback we've gotten is "thank you," right?

The reason we can do that is because the printer doesn't care if it's printing a straight line or a zigzag or a curve, right?

So you can kind of open up your imagination and not be restricted by time or cost when you're designing the home.

And you can see that really highlighted here.

Right?

So on this home, we wanted to call to kind of large sequoia trees.

Right?

And you can see that these walls have kind of high undulation at the bottom of the wall and then really smooth out to the top.

So not only varying kind of horizontally but also vertically as you move up the wall.

Ross: Yeah.

So literally limitless as far as how you can design and get those undulations and the look that you guys want.

Conner: Yeah, yeah.

Ross: That is cool.

Conner: That's right.

Ross: Can I see the inside?

Conner: Would love to show you the inside.

Ross: Alright.

Let's go.

Conner: Let's go.

And, Ross, welcome inside, man.

Ross: Wow!

Look at this.

Even nicer inside than it was outside.

Conner: Yeah.

Ross: This is really cool.

Conner: Thanks, man.

Ross: I love the wood, the accents, you know.

This is really cool.

Conner: Yeah.

Ross: Interior finishes?

Conner: Yeah.

Ross: Let's jump right into it.

So I see the bead design there.

Conner: Yeah.

Ross: What are my options?

Conner: Yeah, a lot of options around interior finishes.

You can see on this home we wanted the beads to kind of stand alone, right, and really highlight them.

So we left them raw, which is an option of itself.

If you like the beads and you you want to accentuate that, you can.

Ross: For some people, that's probably what they'll do, yeah.

Conner: Exactly.

The next option would be just to paint it, which we do on many of our projects.

Another really popular option to cover the walls is plaster.

And this home actually has plaster on the walls in the bathrooms.

Tile is an option that we can place on top of it.

And then lastly, you can always fir these walls out, so we'll put some kind of wood studs up against the wall.

And then you can put kind of any kind of wall cover on top of that... Ross: Got it.

Conner: ...that you might need.

Ross: And then cost-wise.

Conner: Yep.

Ross: How are you -- I mean, a lot of efficiencies picked up here.

It seems to be some cool stuff.

But how does that translate into the cost side?

Conner: Yeah, yeah, that's something that we're highly focused on, Ross.

So, I'll start with speed, actually.

Right?

This is something that's really important -- important to us, delivering homes quickly.

We think that's really important to addressing the housing crisis.

There's not enough stock and we need to meet that challenge.

An equally important part of that puzzle is cost.

And so to understand the goal that we were going to hit, we studied the kind of national homebuilding averages.

And what we realized and saw in the data was that framing, sheathing, waterproofing... Ross: Conventional stick build.

Conner: Yeah, conventional stick-built wall system, it's about $35 a square foot.

We were really excited last year to have hit that with our wall system.

So we hit our goal of $35 a square foot.

We exceeded that goal on a couple of cases, and that's what we're averaging right now.

Ross: So you're on par with market right now.

Conner: We're on par, and what the future is going to hold is a home that's delivered faster, at a higher quality, and a lower cost.

So we're excited to get there.

Ross: That's magic right there.

Conner: Yeah.

That's it.

Ross: Now, everything we've seen has been slab-on grade, single family, single story.

Other kind of building types, other heights, basements?

You know, where does the future go for you guys?

Conner: Great question, Ross.

We're getting into developing all kinds of different technologies.

Our chief development coming up is the next iteration of our printer.

So right now we utilize kind of this large gantry system.

Coming next is more of an articulating arm.

And what that does for us is really open up the possibilities around what you can print.

So we're going to be looking at multiple stories and multiple buildings at once... Ross: Nice.

Conner: ...which allows us to do more types of buildings and deliver them more quickly.

Ross: Conner, thank you so much for the tour.

Conner: Absolutely, man.

Ross: Great to see you.

Conner: Thanks for coming.

Ross: We'll see you soon.

Okay?

Conner: Alright, man, see ya.

Ross: See ya.

♪♪ Kevin: We are always looking for contractors who are worth celebrating, and today we meet Aaron Smith.

Aaron is a landscaper and a gardener who is fostering connection and sustainability in the heart of Detroit.

He also has a tool library that gives his neighbors access to landscaping and power tools, and he manages a vibrant garden that hosts farmers markets and community gatherings.

♪♪ Aaron: My name is Aaron Smith, and I am founder and executive director of Motor City Grounds Crew.

This is the East Warren Tool Library.

And look, you can just leverage all of these tools, any of these tools and equipment to do home improvements, to share the love and go out and maybe help the elderly neighbor.

We'll even deliver the tools to your project in your -- in the various neighborhoods in the city.

So that's that's the love of Detroit that we have here at Grounds Crew.

I appreciate you.

Yes, sir.

Yes, sir.

We're going to turn Detroit around despite what others think.

We're not going to have that negative stigma that was attached when folks would come from all over the world.

And so there's just been this push and this sense of pride among us as Detroiters that, hey, we're turning this -- this city around, and I'm proud to be a part of that.

The Grounds Crew brands have been all about maintain the change and known as curb-appeal specialists.

So what does that property look like when you drive by?

How does that curb look?

Is it appealing?

And that's what it's all about.

Let's start with the outdoor space that makes the individuals who live or work or pass through feel better.

It becomes safer places of passage for children to go to and from school.

And so those are some of the driving forces of what we're all about and why we why we do what we do.

My partner, Annie Hakim, and I are co-owners of Featherstone Garden.

So next year I want to make sure we have a collard-green patch.

Annie: Oh, for sure.

Aaron and I have always aspired just to build beautiful spaces that are productive in the city.

Aaron: These just flourished this year.

I'm a guy who likes raw veggies and I just love -- love to eat it raw like that.

Annie: So, when it's ripe, this is how adorable they are.

Aaron: Mm-hmm.

100 years ago, my mother's, uh -- both her grandparents had come to Detroit, had gardens, fruits, vegetables.

And just exploring those places as a kid is great to me.

I loved it.

I happened to get involved in doing some cleanup of the city of Detroit, where I met John George of Blight Busters, and we hit it off swell.

John: I think we both have that same gene where we can see past the dust.

We're turning blight to beauty, like the mayor likes to say.

Aaron: The mayor coined the phrase, an initiative, all about "blight to beauty."

We're all a part of that.

Look at these cool seats.

John: Well, this is all from the mayor.

This is all from the mayor.

Yeah.

Aaron: I mean, John is an energetic guy.

He is something else.

So we had an opportunity that came about to kick off a program within the non-profit that brought in a cohort of returning citizens, being those that were incarcerated and now out.

And so drawing from some of my military background, I thought that, "Oh, yeah, we can do this, John.

We're gonna put this together and we can just have a roundtable, not just of what's the technical aspect of things, but let's teach them the soft skills.

Let's teach them how to engage with others and go from there."

And so that became a success.

I would say to -- particularly to young people that while you may either consider yourself not college material or you may say that "I don't want to go to college," but a skilled trade can be a very valuable, lifelong, rewarding experience because that trade that you pick up, no one else can take -- take away from you that skill.

So I say bravo to those who choose to go into skilled trades, or who consider it as an alternative path.

I wanted to continue to show the way, and here's a place that we can make better throughout the city of Detroit, no matter where we live or where we find a home or where we find our workplace.

I do it for love.

Love.

One word -- love.

Kevin: Do you know a contractor in your area who's worth celebrating?

If so, write to us and let us know who they are.

♪♪ Hey, Tommy.

Tom: Hey, Kevin.

How are ya?

Kevin: Alright.

So, keeping your steel sharp?

Tom: You got to keep it sharp if you're going to turn wood.

Kevin: Yeah.

And apparently, if you're going to turn wood, you need a new lathe.

Look at that thing.

Tom: We needed a new lathe, a bigger and heavier duty lathe.

Kevin: Alright.

What are you thinking of turning?

Tom: I'm actually thinking about turning a square bowl.

Here's one right here, a little square bowl.

Kevin: What?

You can turn something square?

Tom: Yeah.

Kevin: How the heck do you turn something square?

What's this species?

Tom: This is solid teak.

Kevin: Wow.

That's gorgeous, huh?

Tom: And I got this one here.

We could turn with four legs.

Kevin: Oh, yeah.

Tom: Legs like that and the bowl set in the middle.

Kevin: So are we going to do one of these or...?

Tom: I think I'm going to turn one with the four legs, but I'll make one a little bit bigger.

And I got two species here.

I got bubinga and African mahogany.

Kevin: Oh, wow.

Those are beauties right there.

Tom: Yeah, it's pretty wood.

It's exotic.

Kevin: Which one you thinking?

Tom: I think I might do the bubinga.

Kevin: Okay.

Bigger and bubinga.

Tom: Alright.

So the first thing I want to do is I want to make the block square.

So I'll take an eighth of an inch off of this side.

Now we need to find the center.

Walk from corner to corner.

Now we got to drill a hole right there so we can mount it to the lathe.

[ Drill whirring ] Alright.

That should be good.

Put the lathe forward.

Low speed.

I put a woodworm screw in the chuck.

Will attach the block in the hole that we just drilled.

Kevin: Okay.

Tom: Into that.

Kevin: So that's attached to the chuck.

Tom: Right.

Kevin: How does that feel?

Okay?

Tom: It's good.

Yeah.

Kevin: So what is generally the plan, Tommy?

Like, what's your approach?

Tom: Alright.

So I'm going to do the bottom first, underside of the bowl.

Kevin: Pull in the -- I want to call this the prototype.

Tom: Yeah.

We're going to define the legs and turn the bottom.

I also want to make sure that the bottom of the bowl is higher than the bottom of the leg so it looks like it's floating on a table.

Kevin: So you're basically -- this part here, you're turning that right in the middle here.

And what you leave behind on the four corners becomes your legs?

Tom: Right.

And you just want to make sure you don't get hit by those legs when they come by.

So you've got to get in there with the tool because you don't want to break the leg off.

Kevin: Yeah.

Tom: So now I'm going to just flatten the bottom and then go after the center location and get that bowl started.

[ Clacking ] Turn a lot of air.

You can hear the skipping of the tool.

[ Clacking continues ] Okay.

So you can see all the clear wood.

Nice, smooth.

So now I'll go after the bottom of the bowl.

♪♪ ♪♪ ♪♪ ♪♪ ♪♪ I'm now creating a round mortar so I can attach the bowl to the chuck so I can turn the inside.

♪♪ ♪♪ It's a lot easier to keep the bowl mounted and turning on the lathe so I can sand it.

♪♪ Alright.

We're going to put a little bit of oil and wax on it.

Put it in.

I'll rub it around and we're going to... Kevin: Oh!

Look at that color come out.

Tom: Yeah.

It brings it right out.

Kevin: Yeah.

Tom: I want to get it on kind of thin.

You have to do this outside without the lathe spinning.

Kevin: That's just beautiful wood.

Tom: It turns nice too.

Alright, so now we're ready to turn it around and do the inside.

Kevin: It gets me excited just seeing the back side there, how rich that looks.

Tom: It definitely looks good.

Alright, so now we'll take this off.

[ Grunts ] Now, see if I cut the hole right.

Kevin: Good fit.

Look at you, Pops.

Tom: Huh?

Huh?

Kevin: Look at you.

Tom: Once in a while, you get lucky, sonny.

Kevin: It seems like it happens a lot with you.

Tom: [ Chuckles ] Now that it's flipped, it's time to turn the inside of the bowl.

♪♪ ♪♪ ♪♪ ♪♪ Unlike the bottom, I'm going to put a polishing or a sanding paste in here before we use the oil.

♪♪ So this is where we're going to put the oil on.

Going to use very little and put it on thin.

♪♪ Kevin: Yeah, it sort of just gets a little more rich, a little more depth with each pass.

Tom: Yeah.

Kevin: I got it.

Tom: Don't let it fall now.

Kevin: [ Laughs ] Never.

Oh, Tommy, that is awesome.

Tom: Yeah, I like that finish.

It's nice and rich.

It brings out the depth of the grain.

Kevin: The depth, the wood.

But I mean, also this shape.

I mean, it's just tremendous.

That's one of your best turns.

I got to say.

Tom: Really?

You think so?

Kevin: Well done.

Tom: It's amazing what you can do with just changing the angle of your cut and doing other things.

I mean, you can make a square bowl without legs.

Kevin: I am always amazed.

Tom: Yeah.

Alright.

So we have one more thing to do.

Flip it over.

Kevin: Oh, yes.

Right.

Tom: We got to put a name on it.

Kevin: There you go.

Just went up in value right there.

Tom: [ Laughs ] Probably went down.

Kevin: Uh-huh.

That's awesome.

Nice job.

Tom: Thanks for your help.

Kevin: Alright, well, that's it for us.

But if you've got questions or ideas for another build-it, we'd love to hear from you.

So until next time, I'm Kevin O'Connor.

Tom: And I'm Tom Silva.

Kevin: For "Ask This Old House."

♪♪ Kevin: Next time on "Ask This Old House"... do your stairs need a refresh?

Mauro shows a homeowner how a fresh coat of paint can elevate the look.

Then we hear about some new tools our team is using in the field.

Mark: They are easy to use.

There's a little knob on there, Kevin.

Kevin: And Heath helps a homeowner install a set of sconces.

Man: Can it go up a little bit higher?

Kevin: All that on "Ask This Old House."