Cracked open an old concrete manual from 1972 and found a wild stat

I was digging through a box of junk my uncle left me (he poured driveways in the 70s) and found this beat-up Portland Cement Association handbook. It says back then, the average residential driveway used a 1:2:3 mix with 5 bags of cement per yard, and guys were finishing by hand with wooden floats. What got me is the stat that a 6 inch thick slab back then cost about 12 cents per square foot. Can you imagine that today? Has anyone else run across old school specs that blew your mind?

3 comments

3 Comments

jana50918d ago

and the thing is that 12 cents a sq ft probably included the labor too right? i found a similar old booklet from my grandpa who did foundations in the 60s and it had a spec for what they called "high strength" concrete at 3000 psi and the cost breakdown was so low i thought i was reading it wrong. 5 bags a yard was standard for everything back then, now you're lucky if a ready mix truck shows up with the slump right. makes you wonder how they got so much done with so little tech.

thomas.river18d ago

Ha! 12 cents a foot and you're wondering if it included labor? That's adorable. At that price they probably paid you in pocket change and a pat on the back. Those old guys must have been magicians or just worked like pack mules. I can barely get a quote under $8 a square foot now and the concrete still shows up looking like soup half the time. They didn't need fancy tech because they had the one thing we don't have anymore: guys who actually knew what they were doing.

juliaa6518d ago

The 1:2:3 mix with 5 bags per yard actually made for some pretty good concrete, but that 12 cents a square foot figure is almost certainly material cost only. Labor would have added another 10-15 cents on top of that, depending on the crew. A lot of guys back then were getting 3000 psi mixes with that 5 bag standard, but the slump was way stiffer than what most finishers deal with today. They didn't have superplasticizers so they ran it dry and worked it hard by hand. The real trick was knowing how to handle the mix without all the modern admixtures we lean on now.

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