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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)

#91

Post by dukeyukey »

jmiskovic wrote: post #70
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…

Do we want 100 year old buildings? I don't think we can predict the needs of building even 20 years into the future. City layout could change drastically. Monumental buildings should last a long time, but not every structure. The alternative is to build from wood whenever possible, and capture extra cabon in building material. This increases market need for wood and therefore forestation.

The house I grew up in in rural UK was built in about 1910. My university accommodation was built in the 1880s. The first place I lived in when I moved to London was Victoria, as is where I'm living now. The newest place I've lived for longer than a few months was a flat-share in a 1960s block. For huge amounts of people, >100 year old housing is the norm.

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

#92

Post by ben_w »

jmiskovic wrote: post #70
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…

Do we want 100 year old buildings? I don't think we can predict the needs of building even 20 years into the future. City layout could change drastically. Monumental buildings should last a long time, but not every structure. The alternative is to build from wood whenever possible, and capture extra cabon in building material. This increases market need for wood and therefore forestation.

I’m looking to buy a place in Berlin, and from the search results it feels like half of the apartment buildings are from 1880-1910. I’m renting in a very old (not sure exactly how old) building, and it is… fine. It has been renovated, it is warm, it has double glazing. The only thing wrong with it is the walls are too thin for modern sound systems, but even that is less of a problem here than (for example) my university accommodation in Aberystwyth, because Germans care a lot about quiet time. The only reason I’m skipping anything pre-1950 is that I want to own it for at least 30 years.

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

#93

Post by throw0101a »

jmiskovic wrote: post #70
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…

Do we want 100 year old buildings? I don't think we can predict the needs of building even 20 years into the future. City layout could change drastically. Monumental buildings should last a long time, but not every structure. The alternative is to build from wood whenever possible, and capture extra cabon in building material. This increases market need for wood and therefore forestation.

> Do we want 100 year old buildings? I don't think we can predict the needs of building even 20 years into the future.

My parents live in a house that was originally built in the 1890s. It first had a fire place and wood stove for eating/cooking (surmised via chimneys), then it had gas lighting (some pipe are still in the walls), then it knob-and-tube lighting, then modern electrical lighting and cooking.

Walls were replaced, insulation added, etc. Lots of internal changes.

But the foundations and external brick is original (AFAICT).

Buildings are just boxes for people which keep the cold/heat/moisture at a comfortable level. As long as the "bones" of the buildings are good seismically, the "skin" has proper environmental control, then you can shuffle the inside around without too many issues.

Design/build things with minimal internal load-bearing walls and things can be shuffled fairly easily. Perhaps also use trusses instead of rafters as well for easier running of piping/wire.

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

#94

Post by pornel »

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.

London especially suffers from lots of shoddy conversions.

However, buildings built today to today's modern standards (with a little foresight) could easily be fine 100 years in the future. I'm not talking about fragile glass showpieces, but simple properly insulated homes built from durable materials.

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

#95

Post by rowanG077 »

darawk wrote: post #16
cameldrv wrote: post #13

Earlier quoted context omitted.

This seems unlikely. Clothing is about a $1.3 trillion market, against a world GDP of about $80 trillion. I doubt that an industry that's 1.6% of GDP is contributing 10% to carbon emissions. Also, as pointed out below, the "fashion industry" includes all clothing. Beyond food and water, I'm not sure what would be more necessary than clothing.

The overwhelming majority of clothing produced is totally unnecessary. The fast fashion industry produces an insane amount of clothing, way beyond what is necessary for utilitarian purposes. I don't doubt that it causes that much CO2 emission, especially if you factor in the shipping cost from the places that manufacture it.

I believe this is generally true of any utility. We can all live of soylent or something instead of moving around foods that spoil easily for example. We could all also live in large concrete block where everyone has a small room and houses don't exist. All of that would be hugely more efficient but I doubt you or many other people would like that.

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

#96

Post by nom »

throw0101a wrote: post #93
jmiskovic wrote: post #70

Earlier quoted context omitted.

Do we want 100 year old buildings? I don't think we can predict the needs of building even 20 years into the future. City layout could change drastically. Monumental buildings should last a long time, but not every structure. The alternative is to build from wood whenever possible, and capture extra cabon in building material. This increases market need for wood and therefore forestation.

> Do we want 100 year old buildings? I don't think we can predict the needs of building even 20 years into the future. My parents live in a house that was originally built in the 1890s. It first had a fire place and wood stove for eating/cooking (surmised via chimneys), then it had gas lighting (some pipe are still in the walls), then it knob-and-tube lighting, then modern electrical lighting and cooking. Walls were…

> 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 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?

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

#97

Post by decasteve »

nom wrote: post #96
throw0101a wrote: post #93

Earlier quoted context omitted.

> Do we want 100 year old buildings? I don't think we can predict the needs of building even 20 years into the future. My parents live in a house that was originally built in the 1890s. It first had a fire place and wood stove for eating/cooking (surmised via chimneys), then it had gas lighting (some pipe are still in the walls), then it knob-and-tube lighting, then modern electrical lighting and cooking. Walls were…

> 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…

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.

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

#98

Post by decasteve »

ehou wrote: post #23

The article doesn't mention one alternative: CLT (cross laminated timber) as a building material for houses and flats. See https://www.bbc.com/future/article/20190717-climate-change-w... for example. Using CLT (and passive house principles) can reduce the total CO2 emmissions of a house by 90% in its total life span. The wood in CLT stores carbon and the passive house principles reduces energy needs.

Using actual timbers in a place like Canada should be the norm. Many of the biggest trees are left after a clearcut because they're just too big. When everything around them is cut they tend to die quicker (due to exposure). If they do get cut and milled, they often get processed into dimensional lumber (2x4s) instead of being used as timber.

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

#99

Post by crucialfelix »

manfredo wrote: post #26
aero-glide wrote: post #4

Very interesting, didn't expect it to be that high. Another thing I came across recently : The fashion industry is responsible for 10 % of annual global carbon emissions. Source : https://www.worldbank.org/en/news/feature/2019/09/23/costo-m...

Statistics on how much CO2 something emits can vary wildly. For instance, meat consumption has high CO2 emissions when you include the CO2 emitted by transporting grain to feed animals. But most typical studies would include that under emissions due to transportation. Hence why you can have some studies claiming meat accounts for a double-digit percentage of emissions while others claim that all agriculture contribut…

These different sources are classified as Scope 1 2 and 3:

- Scope 1 emissions are direct emissions from owned or controlled sources. - Scope 2 emissions are indirect emissions from the generation of purchased energy. - Scope 3 emissions are all indirect emissions (not included in scope 2) that occur in the value chain of the reporting company, including both upstream and downstream emissions.

So grain purchased and shipped to the animals is measured under Scope 3. Powering the lights and machinery on the farm is Scope 2.

It's tricky and inexact to do GHG accounting, but the same methodology and emissions factors are used everywhere so at least it's comparable between companies and products.

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

#100

Post by yourapostasy »

ehou wrote: post #23

The article doesn't mention one alternative: CLT (cross laminated timber) as a building material for houses and flats. See https://www.bbc.com/future/article/20190717-climate-change-w... for example. Using CLT (and passive house principles) can reduce the total CO2 emmissions of a house by 90% in its total life span. The wood in CLT stores carbon and the passive house principles reduces energy needs.

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 without active mechanical assistance that keep humidity at or below 40% and temperature variation to within ±10° C in temperate zones.

[1] https://www.bhhomeinspections.com/building-materials-life-ex...

[2] http://www.woodcentral.com/woodworking/forum/archives.pl/bid...

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