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Cement is the source of 8% of the world's CO2 emissions (2018)

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Re: Cement is the source of 8% of the world's CO2 emissions (2018)

#141

Post by nemo44x »

refurb wrote: post #128
nom wrote: post #96

Earlier quoted context omitted.

> Buildings are just boxes for people which keep the cold/heat/moisture at a comfortable level. So true. With the knowledge we have now about building materials you could create a very versatile, rigid, energy efficient base structure that lasts > 100 years, and adapt/update the internals to the current needs. You could even change the room layout completely. I live in Europe and I can't understand why houses in the…

Renovate every 20 years? There are plenty of wood houses that are hundreds of years old and have had minimal renovation to the wood frame.

Yeah if you can keep it dry (take care of roof and siding) and keep termites away they can last a long time. Especially older homes that have sturdier frames (when a 2x4 was really 2x4) built with old growth wood which tends to have tighter grain and therefore more strength.

Re: Cement is the source of 8% of the world's CO2 emissions (2018)

#142

Post by nemo44x »

lotsofpulp wrote: post #86
notahacker wrote: post #80

Earlier quoted context omitted.

> Do we want 100 year old buildings? At least a fifth of the UKs housing stock is over a century old, so the answer to that question is yes, if they're built properly ...

I haven’t been impressed by any of the old UK houses I’ve been in, from rowhouses in London to detached houses in a midlands to mansion in Cotswald. The insulation, pipes, and wiring all are quite inferior to modern standards.

We call that “character”.

My biggest issue with old homes is the layouts tend to be weird for today’s uses. Where I live many of the homes have a lot of small rooms and and narrow doorways instead of larger ones, for instance.

This of course goes back to conserving heat. But it makes house hunting difficult when trying to find a house with a layout you like.

Re: Cement is the source of 8% of the world's CO2 emissions (2018)

#143

Post by ValentineC »

teruakohatu wrote: post #65
BossingAround wrote: post #29

Earlier quoted context omitted.

> High end selvedge jeans might run a couple hundred bucks, but they will last a decade. Is there any data supporting this? Because while I think this is our intuition, i.e. "it's expensive therefore it's better quality," I wonder if there's any way we could verify this other than anecdotal evidence.

You see the British aristocracy wearing 30+ year old shoes that look as good or better than they did when they were new. I think it is common sense that emissions are far lower for extreme-luxury clothing that can be repaired and is timeless verses disposable clothing that last one or two years.

I'm not sure if jeans that are torn/blown out can be seamlessly mended the way shoes can be.

Re: Cement is the source of 8% of the world's CO2 emissions (2018)

#144

Post by refurb »

nemo44x wrote: post #141
refurb wrote: post #128

Earlier quoted context omitted.

Renovate every 20 years? There are plenty of wood houses that are hundreds of years old and have had minimal renovation to the wood frame.

Yeah if you can keep it dry (take care of roof and siding) and keep termites away they can last a long time. Especially older homes that have sturdier frames (when a 2x4 was really 2x4) built with old growth wood which tends to have tighter grain and therefore more strength.

This is true. Longevity of wood homes varies a lot by location.

California? They last a long time. Deep South? I assume they don’t last as long. Canada? They last a long time.

Re: Cement is the source of 8% of the world's CO2 emissions (2018)

#145

Post by yourapostasy »

ehou wrote: post #104
yourapostasy wrote: post #100

Earlier quoted context omitted.

While CLT has been certified for 60 years, I don't know how the adhesives they are using are certified for that long. The working life of common industrial adhesives is remarkably short [1]. The key is not just moisture control, but also temperature regulation. With rigorous humidity and temperature regulation, some adhesives have an as-yet undetermined lifespan. I'm still looking for transportable passive designs wi…

There is also CLT without glue, see my other comment. Check https://www.youtube.com/watch?v=4j_UjIshzMc . "passive designs without active mechanical assistance" - do you mean passive (highly insulated, air tight) designs without mechanical ventilation?

Thanks, I follow Matt so I saw that, but couldn't figure out how they made the exterior wood stand up to the elements.

Yes, PassivHaus or even NetZero type standard, but without an electrically-powered ERV. I don't think it is possible, so I've been looking at minimizing the power requirements.

Re: Cement is the source of 8% of the world's CO2 emissions (2018)

#146

Post by stjohnswarts »

barumi wrote: post #119
shortercode wrote: post #68

The largest issue with concrete is that we misuse it. As a building material it has great thermal mass ( aiding temperature stability ) and longevity. But all too often buildings are poorly designed for renovation, and hence end up being torn down after a couple of decades. A small fraction of the useful lifetime of the structure. Any building using concrete for a structure should be aiming to last at least 100 years…

> Any building using concrete for a structure should be aiming to last at least 100 years. I don't know which country you have in mind but in Europe the construction industry by law is obligated to design concrete structures for residential buildings that ensures a useful life of at least 50 years, and by definition that means that the building structure shall not require maintenance for at least 50 years. Moreover,…

Maybe in Europe, but in the United States if you want to tear down a building and build another one, there is about a 99% chance you can do that and get the paperwork for it without too many hurdles other than NIMBYs.

Re: Cement is the source of 8% of the world's CO2 emissions (2018)

#147

Post by stjohnswarts »

lostlogin wrote: post #137
decasteve wrote: post #97

Earlier quoted context omitted.

You are not wrong. However, houses could still be built from wood like the 500 year old houses and churches made with actual timbers. Timber framed houses would use a lot less wood in the long run due to less waste and greater longevity (especially when coupled with bricks and concrete). Milling large trees down to 2x4s and coupling it to drywall to build homes that don't last is a travesty.

What are you counting as a house that hasn’t lasted? 50 years? 100? The house I am in was built in the 1940’s by the state as an employment and housing scheme for returned servicemen post WW2. It’s wood framed and has a fair few years of life left if cared for. The bulk of NZ houses are wooden, and have been for its entire history. They are also cold and are often damp, though these problems can be solved with decent…

I think that Europeans just are biased against wood frame houses. I've heard this argument over and but a wood frame house can easily last 100+ years with maintenance and owners who care about what happens to it.

Re: Cement is the source of 8% of the world's CO2 emissions (2018)

#148

Post by nom »

stjohnswarts wrote: post #147
lostlogin wrote: post #137

Earlier quoted context omitted.

What are you counting as a house that hasn’t lasted? 50 years? 100? The house I am in was built in the 1940’s by the state as an employment and housing scheme for returned servicemen post WW2. It’s wood framed and has a fair few years of life left if cared for. The bulk of NZ houses are wooden, and have been for its entire history. They are also cold and are often damp, though these problems can be solved with decent…

I think that Europeans just are biased against wood frame houses. I've heard this argument over and but a wood frame house can easily last 100+ years with maintenance and owners who care about what happens to it.

OP here. I guess you are right about the bias. I've learned a lot from this thread, thank you!

Re: Cement is the source of 8% of the world's CO2 emissions (2018)

#149

Post by nom »

krab wrote: post #134
throw0101a wrote: post #114

Earlier quoted context omitted.

> I live in Europe and I can't understand why houses in the US are built with wood and drywall. It surely must be cheaper to use bricks/concrete and then renovate it fully every 20 years, or am I wrong here? I would think that renovations are much easier to do, regardless of the time interval between them, with wood and drywall. Drywall can be torn apart with by someone with just their hands; wood may need some cutti…

Why would you remove concrete and masonry every 20 years? I don't have much experience with wooden houses, so I don't know if it's the case there. But in brick houses renovation often means fixing what's broken and adding modern technologies such as insulation. Moving or adding walls can easily become quite a large scale project.

I think he means changing the room layout. In Europe, usually all the walls are 'set in stone'. Using a combination of masonry/concrete for the outer shell and timber/drywall for the internal walls would eliminate this problem though.

Re: Cement is the source of 8% of the world's CO2 emissions (2018)

#150

Post by nom »

immmmmm wrote: post #120

Also the power needed to grind clinker down to powder is huge, overall comminution (grinding) industrial processes are among the biggest electricity consumer in the world. Cement ball mills are less than 1% efficiency. https://en.wikipedia.org/wiki/Cement_mill Having done two postdocs in the field i can tell its not progressing very fast...

Oh wow that is interesting! Thank you!
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