How come more new builds don't use all concrete?

[Anonymous]

ICFs are not a great building medium above ground.

[Anonymous]

Anonymous wrote:I want a straw bale house.

I'm holding out for a cob house.

[Anonymous]

Hempcrete or you're not really trying.

[Anonymous]

Anonymous wrote:concrete walls have an r value of around .1 per inch, so basically a thermal conductive highway.

What are you talking about? You think that is the only calculation for efficiency?

[Anonymous]

The funny part about this is that everyone is assuming that homes are actually built properly. They aren't.

99% of contractors don't look at, care about, know how to read, or apply specifications.

The next big house bubble will be in 8-15 years when all of these house were thrown up over the past few years start to fail. You are going to have full neighborhoods of several hundred homes and a bunch of close in neighborhoods with unhabitual homes that people will walk away from and mortgage companies will not be able unload them.

[Anonymous]

Anonymous wrote:

Anonymous wrote:concrete walls have an r value of around .1 per inch, so basically a thermal conductive highway.

What are you talking about? You think that is the only calculation for efficiency?

"What am I talking about?" I'm talking about putting in a concrete wall for a single or two story house that has a wide profile for the wall assembly with almost no insulating value. So then you have to add significant width with a framed wall and insulation on the interior, or layers of XPS, EPS, or polyiso on the exterior. What is the point of that significant inefficient wall assembly with an enormous carbon footprint?

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:concrete walls have an r value of around .1 per inch, so basically a thermal conductive highway.

What are you talking about? You think that is the only calculation for efficiency?

"What am I talking about?" I'm talking about putting in a concrete wall for a single or two story house that has a wide profile for the wall assembly with almost no insulating value. So then you have to add significant width with a framed wall and insulation on the interior, or layers of XPS, EPS, or polyiso on the exterior. What is the point of that significant inefficient wall assembly with an enormous carbon footprint?

You aren't comparing apples to apples or considering the whole picture. You can't compare 1" of concrete to 3/4" sheathing. We have 4" and 6" prestressed concrete walls. And then we have continuous insulation behind thermally broken metals studs. So the efficiency is better than sheathing with studs and insulation between the studs. Not to mention the continuity of concrete vs the seams/joints of a stick built house.
As far as the carbon footprint, our 11k sf house was, foundation set, "framed" (walls, interior perimeter and 40% of interior walls studded & insulated, 3 floors ready "framed" for wood flooring), exterior finish complete, roof sheathed in 3 days. And completely enclosed in 7 days.
Think about all of the labor, equipment, deliveries going to and from a traditional stick built site to accomplish that over weeks or months.

Plus there is a lot more room for efficiency error in a traditional stick built house.

[Anonymous]

Anonymous wrote:The funny part about this is that everyone is assuming that homes are actually built properly. They aren't.

99% of contractors don't look at, care about, know how to read, or apply specifications.

The next big house bubble will be in 8-15 years when all of these house were thrown up over the past few years start to fail. You are going to have full neighborhoods of several hundred homes and a bunch of close in neighborhoods with unhabitual homes that people will walk away from and mortgage companies will not be able unload them.

Yeah, but there's no reason to believe that concrete houses will be built any differently.

[Anonymous]

Anonymous wrote:

Anonymous wrote:The funny part about this is that everyone is assuming that homes are actually built properly. They aren't.

99% of contractors don't look at, care about, know how to read, or apply specifications.

The next big house bubble will be in 8-15 years when all of these house were thrown up over the past few years start to fail. You are going to have full neighborhoods of several hundred homes and a bunch of close in neighborhoods with unhabitual homes that people will walk away from and mortgage companies will not be able unload them.

Yeah, but there's no reason to believe that concrete houses will be built any differently.

Sure there is. Far fewer penetrations, joints, seams. Harder to hide issues, most issues would be very apparent.

Everyone uses zip wall sheathing, hardly any contractor does it correctly and that is something that is utilized everyday everywhere.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:concrete walls have an r value of around .1 per inch, so basically a thermal conductive highway.

What are you talking about? You think that is the only calculation for efficiency?

"What am I talking about?" I'm talking about putting in a concrete wall for a single or two story house that has a wide profile for the wall assembly with almost no insulating value. So then you have to add significant width with a framed wall and insulation on the interior, or layers of XPS, EPS, or polyiso on the exterior. What is the point of that significant inefficient wall assembly with an enormous carbon footprint?

You aren't comparing apples to apples or considering the whole picture. You can't compare 1" of concrete to 3/4" sheathing. We have 4" and 6" prestressed concrete walls. And then we have continuous insulation behind thermally broken metals studs. So the efficiency is better than sheathing with studs and insulation between the studs. Not to mention the continuity of concrete vs the seams/joints of a stick built house.
As far as the carbon footprint, our 11k sf house was, foundation set, "framed" (walls, interior perimeter and 40% of interior walls studded & insulated, 3 floors ready "framed" for wood flooring), exterior finish complete, roof sheathed in 3 days. And completely enclosed in 7 days.
Think about all of the labor, equipment, deliveries going to and from a traditional stick built site to accomplish that over weeks or months.

Plus there is a lot more room for efficiency error in a traditional stick built house.

I don't want anyone with an 11K SF house lecturing me about efficiency or sustainability!

Listen, I'm happy that you're happy with your house. But if you're coming here expecting affirmation for being eco-conscious, economical and just generally smart for building your concrete house, you've come to the wrong place. And while you've clearly absorbed all of the marketing information from the ICf people, your ignorance of building science and construction in general is kind of painful.

You apparently don't know that the IRC -- the International Residential Code, the building code in effect in DC and environs -- now requires continuous insultation on a wood-framed house. That's code-minimum -- the worst house you can legally build. You still haven't told us what the R-value of your miracle house is, but no matter what it is I'm sure there are wood-framed houses being built that would put it to shame. Google "Pretty Good House" for examples. It's probably not that much more -- if anything -- than code minimum.

If speed of assembly is important to you, check out panelized or modular construction. There's an outfit in Baltimore called Blueprint Robotics that builds custom houses as big as yours in a CNC factory, then ships them in pieces for on-site assembly. They stand up a house as big as yours in one day. With continuous insulation and air sealing all around.

Again, if you really want to get the lowdown, go to a site that specializes in building science. I recommend GreenBuildingAdvisor.com. They'll set you straight.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:The funny part about this is that everyone is assuming that homes are actually built properly. They aren't.

99% of contractors don't look at, care about, know how to read, or apply specifications.

The next big house bubble will be in 8-15 years when all of these house were thrown up over the past few years start to fail. You are going to have full neighborhoods of several hundred homes and a bunch of close in neighborhoods with unhabitual homes that people will walk away from and mortgage companies will not be able unload them.

Yeah, but there's no reason to believe that concrete houses will be built any differently.

Sure there is. Far fewer penetrations, joints, seams. Harder to hide issues, most issues would be very apparent.

Everyone uses zip wall sheathing, hardly any contractor does it correctly and that is something that is utilized everyday everywhere.

You ever worked with concrete? Once it's poured there's no way short of coring or xraying to tell it was done properly.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Concrete is expensive. It has terrible ecological impact. It's not very insulating, so you'd still have to insulate it, so the walls would have to be very thick.

A properly built wood house has few problems.

Not true at all. Concrete homes are way better insulated than homes built with wood and walls. You will save as much as 30% in energy in a concrete home.

So tell us, oh building science master, what is the typical wall r-value for a concrete house? And what is code minimum in the US?

Yeah, seriously. A ding-dong has invaded the thread.

[Anonymous]

Anonymous wrote:Brick too! Why isn't anyone using beautiful brick anymore?! It's such a shame.

Cost....brick is expensive - laid down one at a time, adds significant time to the project, AND you have a
work around the weather (freezing temps, rain, etc). Signed....builder.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Concrete is terrible for the environment.

https://amp.theguardian.com/cities/2019/feb/25/concrete-the-most-destructive-material-on-earth

https://psci.princeton.edu/tips/2020/11/3/cement-and-concrete-the-environmental-impact

https://climate.mit.edu/explainers/concrete

https://www.fairplanet.org/story/concrete-climate-change-environmental-injustice/

https://www.greenspec.co.uk/building-design/environmental-impacts-of-concrete/

Maybe the initial cost upfront is more to the environment, but concrete structures use a lot less heating and cooling over the lifetime of the structure. How much environmentally better is building a home with cheaper materials if you have to constantly fix it or even knock them down and build new again when they've reached their end of life? Concrete can last for way longer.

I'm still waiting for you to provide the r-value numbers that show that a concrete building is better-insulated.

Concrete or wood isn't the only thing providing the r.

But 60lb concrete has r of about .52/" 4" would be +/- 2. 1" Sheathing is about 1.25. But there are still a lot for places for loss. ie joints/intersections of multiple elements, fasteners etc.

[Anonymous]

Anonymous wrote:I want a straw bale house.

DH's good friend from childhood built a ton of these out west. Skeptical builders would come by for a tour of his place and some were converted.