Sort-of Hoax Watch: Bad Reasoning

This isn't properly a Hoax-watch article, but I found some funky logic while poking the internet for facts about concrete. An Irishman writes:

The concrete industry has been unfairly characterised in recent years as a ‘culprit’ in the environmental equation. [...] Environmental performance is of course ‘relative’ and substituting one construction material for another is a viable proposition if one material is more friendly to the environment than another. However, to date, the Irish Concrete Federation have not unearthed any scientifically based independent study, in Ireland or abroad which suggests that substitution of concrete with timber or steel is of benefit to the environment. On the contrary, recent figures produced by an independent group of leading 1Irish consultants show that one tonne of softwood contains 10 times the embodied energy and 8 times the embodied CO2 as one tonne of structural concrete. Comparing concrete to steel, steel consumes 30 times the amount of energy in its production than concrete for the same mass of product.
See what's going on there?

First, consider concrete. Now consider a tree. What's different about the two of them? What, specifically, is different in their "embodied energy" and "embodied CO2"? Yes, that's right - the tree, even a tree used to build a house - receives its energy from the sun, free of charge to humanity, and is actually sequestering carbon dioxide taken out of the air - and will continue to do so until it's burned. Concrete, on the other hand, was molded in a kiln, most likely with fossil fuel energy, and produced carbon dioxide in the process. Ah assumptions.

Second, consider concrete, then steel. Take an equal weight of concrete and steel. Which do you suppose, you who are probably not a structural engineer but might have some common sense, would go farther in terms of building a structure? If you answered steel, then you're right. Yay!

Concrete is heavier than steel. It's also cheaper.

I'm not trying to say we should replace concrete with wood or steel. They're all totally different materials, and they all have their place (although we should really start doing more interesting things with our steel skyscrapers - even painting them would look much nicer). I object to the horrible reasoning used by some random person I found on the internet.

(Side-note: Why do I go after the random people? Answer: It's interesting and, I hope, informative - at the least, in the form of logic.)

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