Concrete slabs & floors
Romn322
| Posted in General Questions on
Is this a question? Or just a lament? Why is it with all our modern technology, there seems to be no way to make a concrete floor feel comfortable? And don’t say you can just use sleepers, I’ve walked on floors with sleepers and there’s zero compression at the sleeper and virtually no bend anywhere else, so that it has virtually the same hardness as the concrete itself. I’m ready to carpet my whole slab in memory foam.
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NAHB says that over half the homes in the US are built on slabs. The documented deleterious consequences on the human body are voluminous. How is this not a thing? Am I the only one to ever think about this, or is it that everyone else gives up immediately because they realize there is no solution?
When I first converted to a no-shoes household, I felt that the hard flooring surfaces were bruising my feet. (I've since adapted and no longer have this sensation.) For comfort, I started wearing slippers and Crocks. FWIW I found tile and hardwood floors uncomfortable until my very flat feet got used to the pounding.
The difference in elasticity between concrete, wood, tile or other hard floor surfaces is minute, far too small to feel. Concrete floors are good conductors of heat and have a high heat capacity so they suck the heat from your feet, which makes them feel uncomfortable.
Michael, this is exactly the answer I was (and also was not) hoping to get when I tapped into the breadth of wisdom on this site. Your answer took me by surprise, because I have lived many years on both and have believed concrete to be painful. You aren't denying that there is a difference in deflection, that would be crazy, but that it's too small to feel, which I can believe. Fascinating! Are you saying my aches, which I feel in my knees & not feet, are psychosomatic? If I'm going to deprogram myself, can you point me to something I can look up that confirms the "too small to feel"? And finally, does this apply to counters, because I also believe that a glass dropped on granite is more likely to shatter than a glass dropped on laminate from the same height.
Doug, I don't have a reference, and should have qualified my comment with it being my educated opinion. There are two characteristics that might come into play: hardness and deflection. Concrete is harder, obviously--it compresses much less in response to a force than wood does. But wood does not compress much under typical loads--for example, a 200-lb footstep over a few square inches may compress wood a few micrometers, but compare that to the padding on your feet, and certainly padding with any shoes or slippers, which will be several orders of magnitude greater than the difference between wood and concrete.
Deflection is also the measure of response to a force. Under normal loads, a concrete slab on grade has essentially zero deflection. Floors framed with lumber are supposed to meet a code minimum deflection of L/360, or 1/360 of the span. For joists with a 12' span, that would be 0.4". But that's a maximum deflection under maximum loading, usually 50 lbs per square foot over the entire floor. An individual walking on a floor will cause much less deflection (unless the floor is built well below code-minimum)--on the order of 1/16th per footstep, or less. That 1/16" is, again, much less cushioning than you have on your feet or in any footwear. Maybe over the course of many hours it adds up to something noticeable, but I find it hard to believe.
Thank you
Also, this may be news to industrial hygenists:
https://www.ishn.com/articles/103571-can-you-stand-it-prolonged-standing-puts-millions-at-risk
Doug,
The exterior built environment we live and work on is almost entirely concrete. The vast majority of construction, except for a small part of North America uses concrete underfoot. That's a perhaps an unfortunate reality. Concrete is a structural material. If it is inappropriate as a finished floor surface it needs to be covered by a cushioned material, not itself modified to be soft.
You are right, and I love the different ideas these posts can bring. I never thought of making the concrete itself soft... Seems inherently impossible... but a really interesting thought experiment. I was more thinking what we could put directly over the concrete that would remediate the disadvantages in a durable, inexpensive, and green way. I'm a little skeptical of carpet pad for the 1st & 3rd reasons, but may try it given the other options. Thanks for responding!
If you develop soft concrete I want royalties.
Soft concrete is pretty mushy, but unfortunately it hardens by the next day! :-) And it may have footprints... :-)
But you really inspired me to renewed research and search terms so that I learned about horse mats, spring floors for gymnastics, and this useful post from GBA's... cousin?
https://www.finewoodworking.com/forum/aching-feet-knees-vs-concrete-floor
However much cushioning you get from the floor, you can get more from the right shoes.
yes, but
#liberate the feet :)
If you are on your feet a lot, there is a noticeable difference at the end of the day. Concrete is harder on the body.
There is nothing comfortable about having to wear shoes in your house (also it tracks dirt all through out)
I'm trying to figure out what to do, basements are common around here, and I was looking at slab for costs reasons, but don't like the idea of living on a slab, and am not a big fan of the plumbing being set for life, with no chance to ever move it
Trevor,
Have you considered not using a basement slab? There have been a few articles on that recently here on GBA. Michael Maines published his details, the recent BS and Beer, and this article: https://www.greenbuildingadvisor.com/article/another-take-on-a-concrete-free-slab