3D printing a concrete house?

[David]

Interesting technology.

Although billed as a 3D printer I think the main technological advance is the concrete which can be laid from a nozzle and keep its shape. It must set very quickly as well to be able to build a complete single storey house within 24 hours. I wonder how well this would work with normal shuttering as a former just being constantly jacked up?

The walls are dual thickness with cavities (but not continuous) and look as though they should be strong.

Not up to building regulations (unless the concrete is also a very good insulator) as there isn't insulation built into the walls.

Looks pretty good for fast build accommodation on a suitable site, although you would also have to be laying all services prior to the build. That would go with the concrete slab for the base, of course.

It looks to require a flat site, as well.

At the moment I'm trying to work out how this stacks up against a traditional block build using brickies.

As far as I know the main constraint to speed of build is the time it takes for the mortar to go off. You can only lay so many rows of blocks or bricks before you have to leave it alone to cure.

I'm pretty sure there was a mechanical brick layer about 30-50 years ago. Ah, yes.

Haven't seen many of them around on building sites. Still better and faster than me, though.

Cheers

Dave R

[The Natural Philosopher]

Having watched brickies I would say they spend 25% of the time doing nothing productive, 25% moving materials from where te truck left them to where they nmeed them, 40% of the time laying out the strings and 10% of the time actually laying courses.

[Jethro_uk]

I am amazed that of all the jobs that have been mechanised, bricklaying remains an exception.

Mind you, modern dwellings seem quite brick-shy anyway.

[GB]

Are they really saying the entire cost was $10k, at US labour rates? Including clearing the site, laying the foundations, that complicated roof, all the windows and electrics, etc?

The extruded mortar machine is very impressive, and it does allow for those very pretty curves, but a few blokes could run up the blockwork equivalent (without the curves) in much the same time. The blocks and mortar are not expensive.

It's economics, innit? Of the total cost of a house, the cost of a brickie is a tiny part. For example, the cost of the bricks laid in a day is typically several times the cost of the brickie. And the cost of the walls is only a fairly small part of the overall cost.

The robots do exist:

[Andy Burns]

And yet, with all the novel materials and off-site construction methods brick'n'block still remains the cheapest built method - arguably with the other methods, you can get a better insulated house to a more predictable timescale.

[The Natural Philosopher]

Crap. When I built my house the general spilt was 1/3rd material 2/3rds labour.

The brickies cost up to 5 times as much as the bricks they lay, even including the mortar. Same goes for render even moree so - its ALL labour and even slapping on weatherboard is not that quick.

Only when you are fitting out a house does the materials cost exceed the labour cost.

[The Natural Philosopher]

Well no it doesn't.

The developer/builder whos building site I was living in last yeat simpley premakes wooden panels with strawboard walls and 6x3 structural members, eecdts them, and then clads them in brick, weatherboard or render depending.

Way faster than all blockwork and cheap as chips

And that saves money as well.

[Steve Walker]

It's also amazing just how fast a brickie can work when he's being paid a fixed price for a job!

SteveW

[Andy Burns]

faster, but every cost estimate I've seen says you pay more for brick-skinned SIPs, or brick-skinned timber frame.

[The Natural Philosopher]

£20/square meter A brick is about £1 give or take.

60 bricks to the square meter, so if you CAN get that productivity out of the bricklayer yers, the bricks are more expensive. I've never seen it

[The Natural Philosopher]

Depends on how prefabbed your frames are.

[GB]

I've never built a house, but my impression is that the walls go up very fast. It's all the other stuff that takes the time.

[The Natural Philosopher]

TBH walls are just one bit = theres groudnwork amnd site laying out, foundation laying floors, walls, cladding, roofing, ..kitchens floors bathrooms leccy and heating ...the list is long.

>

[James Wilkinson Sword]

Link fixed. You had it wrapped.

There are air gaps, just like the walls in my house. Looks like the air is less free to move around too.

Surely mortar can be made to set at different speeds, and if it's laid by machine they could make it very fast setting?

[James Wilkinson Sword]

You forgot drinking coffee and nattering.

-- =

What advice don't you want to hear from a doctor before an operation? "Whatever you do, don't go into the light."

[dennis]

The limit is on how many courses they can lay in a day. Too many and the wall fails.

Thin joint systems can do a lot more courses in a day but people prefer traditional walls AFAICS.

[DerbyBorn]

Stubborn and traditional. Unorganised. On the phone. Poor planning.

[James Wilkinson Sword]

If builders had brains they'd have a better job.

[GB]

You missed rent off that list. One of my neighbours decided to knock his house down and rebuild it a bit grander.

He decided he needed a basement. By the time he'd piled and dug, he found it kept filling with water. He was on his third lot of builders, last I heard, and the work is in its third year. The house is up and complete on the outside, but it's still being fitted out.

Meanwhile, he's been renting round the corner. I assume that rent is his biggest single cost.