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Sand is heavy af. A ton is only like 20 cubic feet. Still… that’s not very much money.

My eye is twitching remembering a fiasco where someone ordered concrete assuming 1 cubic metre required 1 ton of concrete.

Ever since that I’ve assumed it’s about 2.5 tons per cubic metre. This works much better.

But concrete is measured by volume at least in the US (cubic yards…sigh). I think this is because different mix designs can change the resulting weight. I’ve even heard of adding air to make for better pumping.

Air entrainment is critical for freeze-thaw protection, so any exposed concrete in places that have below freezing should have 5-6% air entrained.

The bags of ingredients at the hardware store are usually 20-25kgs here, and labelled that way.

It’s a silly way to buy a lot of concrete, but does help someone without a tow bar.

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