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How Has Roman Concrete Lasted for Millennia? 1,900-Year-Old Latrine Offers Clues

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Re: How Has Roman Concrete Lasted for Millennia? 1,900-Year-Old Latrine Offers Clues

#231

Post by ascorbic »

benj111 wrote: post #93
ascorbic wrote: post #38

Earlier quoted context omitted.

They weren't torn down because there was better technology available. They were torn down because they were falling apart, or were no longer meeting the needs in that location. I love old buildings – my house is 250 years old – but there's no denying that generally they are less suited to current needs than newer buildings.

Older buildings are generally more flexible though. In the UK, within living memory electricity has become widely available, TV has, gas, internet etc etc. and yet we still build houses without the assumption that some cable isn't going to be modified in the wall some how. There's fairly modern houses that didnt have the 2 courses of brick added to the loft to allow 300mm of insulation to be installed. We are now bui…

When we bought our house, the only plumbing was in a tiny, asbestos-filled lean-to extension added in the 1940s that contained the kitchen, bathroom and toilet. The way people use houses has changed a lot in the past 100 years

Re: How Has Roman Concrete Lasted for Millennia? 1,900-Year-Old Latrine Offers Clues

#232

Post by dredmorbius »

tpm wrote: post #128
gravypod wrote: post #116

Earlier quoted context omitted.

Neither is grout. Grout is water permiable. You shower is water proof from the water proof backing we install the tile on top of. Cement board + roll on or something like kerdi system. https://youtu.be/B5DVpruLygw?si=jD8eMHHGQoWG4hI2

right, but lime will be washed away by the water if no waterproof layer is added

I suspect the term you were looking for in your original comment was insoluble, that is, a substance not (readily) dissolved into water.

Concrete is insoluble (it won't wash away, contrast with lime), but not water-proof.

Re: How Has Roman Concrete Lasted for Millennia? 1,900-Year-Old Latrine Offers Clues

#233

Post by poelzi »

iknownothow wrote: post #74

For those not familiar, the secret ingredients are to do with the Lime Cycle [1]: 1) Quicklime/Slakedlime (Calcium Oxide, CaO) 2) Lime (Calcium Hydroxide, CaOH2) 3) Limestone (Calcium Carbonate, CaCO3) To keep it simple, typically you start with Quicklime (CaO) and after construction you end up with some mix of all three and after hundreds of years, the masonry transitions to mostly Limestone with microscopic traces…

The trick was: Lime CHUNKS, proper volcanic fly ash, salt water + no steel. Self repairing and more flexible

Re: How Has Roman Concrete Lasted for Millennia? 1,900-Year-Old Latrine Offers Clues

#234

Post by modo_mario »

jaapz wrote: post #131
modo_mario wrote: post #58

Earlier quoted context omitted.

>cold in winter >in my region terribly humid You need to actually reduce draft a bit (often old houses like mine tend to accumulate flaws that the elderly living there before didn't fix anymore.) and use a heating sources that matches. Having a fireplace is fine. It could overheat the house whilst also keeping air dryer and it's essentially renewable (compared to the alternatives and houses made of more plastic insul…

Fireplace is extremely inefficient, and really bad for both your (exhaust fumes get into the room anyway), and your neighbors (the smoke doesn't just dissappear) health, though. I love the heat and smell of a good fire as much as the next guy, I'm just not sure it's worth the risk of cancer and respiratory diseases.

If exhaust fumes get into the room too often you're doing it wrong. You shouldn't be able to smell it inside. I've at times made the fire go a little harder to get rid of fumes (kitchen oopsies). My air quality measurer found it remarkably effective.

As for neighbors. That is true but at the same time these things are rather sustainable and from a time when the population density was lower. I think they still have some place outside of cities untill heatpumps come down in price.

Re: How Has Roman Concrete Lasted for Millennia? 1,900-Year-Old Latrine Offers Clues

#235

Post by _n_b_ »

tristor wrote: post #207
SoftTalker wrote: post #178

Earlier quoted context omitted.

Not permitting and regulation? We're told that is the biggest impediment to development.

Permitting and regulation is generally a sub-component to each of the three things mentioned, and can be a major factor in schedule adherence for large scale construction projects. Whether that is the primary impediment or not is often a factor of the specifics of the project (and its design) and the overall environment. During major events (e.g. COVID), materials access and availability was a far more challenging as…

A week late but... in my experience (potentially sector/location specific but I don't think so), most high-risk licensing and permitting activities come before construction starts, and certainly almost always before above-ground construction starts. So regulatory issues may challenge overall project viability, but you tend to know before cash is sunk if you're going to be, for instance, refused planning permission.

Re: How Has Roman Concrete Lasted for Millennia? 1,900-Year-Old Latrine Offers Clues

#236

Post by rewtraw »

andsoitis wrote: post #152
rewtraw wrote: post #147

we can't figure out roman concrete we don't know how ancient megaliths were built centuries old cathedrals and holy places have more intricate masonry and carvings than anything built today (with allegedly more primitive tech) are historians retarded? what's going on here? time is flowing backwards and civilization is declining, but humanity is under a collective trance and can't even see it.

> time is flowing backwards and civilization is declining Why do you think civilization is declining?

you can see it clearly in architecture alone. cathedrals and other ancient constructions are far more impressive than what we build today - they obviously had more prosperity and will for greatness than modern man.

and it doesn't take much of a leap to understand the people who built them were more advanced than officialdom gives them credit for. we are in a period of soullessness, and while we have made technological strides - and are probably in a needed period of materialism to make these strides - in order to move back 'forward' in time we need to integrate both the material and spiritual.

tldr: Kali Yuga doing its thing

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