Cement - How old is too old?

No expert, but dry shelf life is indefinate. Wet shelf life is zip.

Are you sure Roger? I remember reading that part of the problem with the big dig tunnel in Boston is that they used old cement. I seem to recall someone saying it loses it's ability to bond with the sand if it has been sitting around too long. I just don't know what is meant by "too long" .

You can use cement without any problem 6 months after you bought it.

One year shouldn't do any harm to concrete, too.

Two years old cement ... well, you shouldn't use that at all.


However: cement looses its taste after two months - just in case you need it for cooking :wink:


Honestly, you can use it - perhaps add a bit more than you would use normally - to be on the safe side.

Thanks Walter (and Roger) I'll experiment in a small area and see how it gels.

I've just checked it (I've worked as a "concrete unskilled worker" during university holidays ... besides being born in a town with a huge cement indutry - and a football club, called "concrete heads" :wink: ): one year really should work.

Just what we need, Walter. Concrete cookies, tasteless but for the occasional chocolate chip.

Speaking of which, GreenWitch, you know better than to get that stuff on your skin, right? If you don't, I'll tell you now. It is really tough on the complexion.

Actually, I'm fairly experienced with using the stuff and I've got the rubber gloves and face mask at the ready. This is the first time I've ever had the age problem. I prefer my cement fresh, but I just couldn't see the point of throwing out the bags if they were still usable. I'm a very frugal witch.

Fair enough. I'm a very cautious bookkeeper