Is there anyone here who knows approximately how long concrete usually lasts in, for example, an apartment building from the 60s? Can it last for several hundred years or is it a significantly shorter time span that's expected?
Modern concrete, which includes an apartment building from the 60s, lasts at least 100 years. You can read more here: http://www.svenskbetong.se/bygga-me.../hallbart-byggande/bestandighet-och-livslangd
Over 100 years of lifespan doesn't sound too long? But it suffices for my needs. So if I, for example, stay here for another ten years, the new buyers don't need to worry about whether the house needs to be demolished soon.mexitegel said:
That's kind of what I thought, if ancient Roman concrete can last that long (albeit in significantly deteriorated condition), modern concrete should be able to withstand a few hundred years?lat said:
Okay, maybe it's difficult to calculate concrete's lifespan more precisely in that case? If you can't get more precise values than that it can last approximately 100 years or maybe 400 years, or perhaps even longer. I did a quick Google search before I started the thread and only found "more than 100 years" as an answer. That's enough for the consideration regarding my apartment, but one does get a bit curious to know more anywaymexitegel said:At least and approximately are not synonyms. It might as well last 200 years, or 400 years, or even longer, but it is expected to last AT LEAST 100 years.
I am not a concrete expert, but there are many different types of concrete. Therefore, it is not possible to simply answer the question. It simply depends. The concrete used to anchor oil platforms hundreds of meters deep in the sea is likely, for example, different from the one you use to cast a concrete floor. As I believe it was stated on the page I linked, the climate in which the concrete exists significantly affects its lifespan.
No one really knows exactly how long concrete lasts. There are different qualities, and it also depends a lot on how exposed the concrete is to moisture, freezing, etc.
Concrete in a protected environment (no moisture, no wear, no sub-zero temperatures) will surely last for thousands of years. But poorly executed concrete exposed to the elements can be completely ruined after a few decades.
Concrete in a protected environment (no moisture, no wear, no sub-zero temperatures) will surely last for thousands of years. But poorly executed concrete exposed to the elements can be completely ruined after a few decades.
The main problem with concrete reinforced with steel is carbonation. Simply put, it means that the concrete reverts to limestone, which allows the reinforcement to rust once it reaches it. As some have already pointed out, this occurs at different rates depending on how exposed the construction is to weather and the quality of concrete used. For homeowners, the worst affected areas are the undersides of balconies, while indoor concrete can last indefinitely.
It might be appropriate to clarify some concepts here on the forum.
The reason why many Roman structures still exist today is manifold, but to mention a few, they didn't have the same conditions as we have in the Nordic region and were often not reinforced, which can create major problems.
Then onto a common misconception that concrete exposed to moisture is damaged first, this is completely wrong. Concrete that is dry is the most susceptible to corrosion.
Moreover, it is not possible to answer how long the lifespan of a concrete structure is without knowing a number of factors. If you have these, it is relatively easy to calculate the expected lifespan, and then, of course, it can be adjusted with various methods during the concrete's lifespan.
Some crucial factors are, of course, the degree of exposure, W/C ratio, cover thickness, type of aggregate, execution of casting is obviously very important, compaction, curing, etc.
The reason why many Roman structures still exist today is manifold, but to mention a few, they didn't have the same conditions as we have in the Nordic region and were often not reinforced, which can create major problems.
Then onto a common misconception that concrete exposed to moisture is damaged first, this is completely wrong. Concrete that is dry is the most susceptible to corrosion.
Moreover, it is not possible to answer how long the lifespan of a concrete structure is without knowing a number of factors. If you have these, it is relatively easy to calculate the expected lifespan, and then, of course, it can be adjusted with various methods during the concrete's lifespan.
Some crucial factors are, of course, the degree of exposure, W/C ratio, cover thickness, type of aggregate, execution of casting is obviously very important, compaction, curing, etc.
hul said:
You seem to have a good grasp on this. Do you have any rough estimate on how long the concrete in a house with the following characteristics can last before it's time to demolish and rebuild? A condominium from the early '60s, a good association that takes care of and fixes what is needed, balconies are "built-in" the wall and do not protrude outside the building, 3 stories high, located in Umeå on ground that seems to have a lot of stone.Matti_75 said:
Well, that's not the whole truth.Anna_H said:
But to try to answer your relatively complex question, the lifespan is 50 years, so it's already over. Concrete is designed in 3 lifespan classes: 20 years, 50 years, and 100 years. Your house was designed to last for 50 years.
Of course, that doesn't mean the house will collapse the day it turns 50. Damages are repaired and renovations are done over the years, thus extending the lifespan. Moreover, there are safety margins and concrete houses can last incredibly long.
It's important how well the house is cast and maintained. It's very difficult to know the exposure class in which the building is cast without having the drawings. The exposure class of the concrete is incredibly important, and the right class extends its lifespan.