Branching Out Wood

Modern Functional Home Decor by David Wertheimer

Is Using Wood Bad for the Environment?

SustainabilityDavid Wertheimer3 Comments

This post is motivated by a number of conversations that have made me think about the potential contradiction in my environmentalist tendencies and my using wood as my primary medium. Paraphrased for brevity:

  • Friend#1: "You put up solar panels, yet you cut down trees..."

  • Friend#2: "Most people don't know where the 'material' of trees comes from..."

So, here’s my attempt to square this circle.

How much wood is harvested annually?

It's tough to come by well-vetted (and current) stats, but here's a few from Wikipedia:

  • The worldwide growing "stock" of forests is about 434 billion cubic meters (2005).

  • The annual wood harvested for all purposes is about 3.5 billion cubic meters (1991), though estimates of wood used for burning have wide ranges. This represents about 0.8% of the growing stock.

  • The annual "roundwood" (officially counted wood not used as firewood) harvested is 1.5 billion cubic meters (1998).

How much is a cubic meter? If you're familiar with your typical eight foot 2x4, there's about 100 of them in a cubic meter. An average 2000 square foot house uses the equivalent of roughly 1875 2x4s for framing, so that means that was enough wood harvested in 1998 to frame 80 million comfortable homes.


Translating that to my business - I purchase wood by the "board foot", which is one square foot of lumber 1" thick, or one twelfth of a cubic foot. Big projects - such as the 24 oval mirrors for the Southern California carousel rebuild - use a few hundred board feet (about 1 cubic meter).

However, most of my small products, such as this popular lamp, use between a quarter and a half of a board foot. So you could make 150 of them from a cubic meter of wood - or in 1998, if I had cornered the wood market, I could have made 225 billion of these lamps, enough for every person on the planet to have about 30!

But just saying I don't use much ain't much of a defense. So, is using wood good?

What's the alternative to wood?

If you want a lamp, or some coasters, or a shelf, you could purchase something made of plastic, or glass, or any of a hundred other materials. And many of these materials don't involve cutting down a tree. But, many of these materials are far worse for the environment overall taking into consideration all of the “embodied energy” and “embodied carbon” that goes into creating an object.

Said another way, though it’s always better to consume less, if you are going to consume, do it with goods that take less energy to create, and leave less of a carbon footprint on the planet.

Illustrative breakdown of the stages of a product or material life that should be considered when understanding the carbon footprint.

Illustrative breakdown of the stages of a product or material life that should be considered when understanding the carbon footprint.

That's one reason why I'm happy to say that my workshop (and my vehicle) is powered by solar energy; while that's just a small piece of the overall ecosystem, that also reduces the environmental footprint of what I sell.

For a much more scientific and detailed analysis of hundreds of materials commonly used in construction and elsewhere, check out this paper. For example, the average sawn hardwood has about 7-10% the energy per kilo that the typical plastic contains, and about a quarter of the embedded carbon.

In fact, wood has a far lower embodied energy and carbon content than almost every other material that might be commonly used for home decor. So while it’d be better to not purchase anything at all, if you do, use wood!

Is burning wood "bad"?

I periodically host a bonfire to get rid of scraps I accumulate - primarily construction-grade framing wood, but also occasionally scrap hardwood that I just can't find a home for in either my own projects or via with my fellow artists.

This produces soot & ash which isn’t great for the local air quality but - on a small scale from limited camp fires and bonfires - has fairly modest impact. In larger scales, however, there are clearly bad effects: Northern California briefly took the crown of having the world’s worst air quality in mid-November due to the tragic Camp Fire; breathing the unfiltered San Francisco air for a day then was equivalent to smoking a half pack of cigarettes.

Battling the Camp Fire, Nov 2018

Battling the Camp Fire, Nov 2018

Or - not quite as tragic but just as bad for our health - lower-income regions that rely on wood for cooking and heat have very bad air quality, as I personally witnessed in parts of the Himalayas in mid-October. For this reason, it seems parts of China - including Tibet - have outlawed wood stoves, and the U.S. EPA has similarly banned inefficient wood burning stoves a few years back.

But beyond that, does this contribute to global warming, or other types of air pollution?

Goodbye, failed early attempt at a round coffee table, c. Nov 2017.

Goodbye, failed early attempt at a round coffee table, c. Nov 2017.

Wood treated with anything (paint, insect protection, stains), or composite wood products (plywood, particle board, etc.) is a definite no-no, for the very bad toxins that this releases into the air.

But how about "raw" untreated wood? Logs you've cut down from your property, that old pallet sitting in your backyard, or some wood scraps? You may have heard wood referred to as a "renewable" or "carbon neutral" resource - how is this so, if burning it releases CO2 into the air?

That's because that carbon in the tree came from the atmosphere in the first place, as the tree grew from a seed. Trees breathe in CO2, and breathe out O2, in the process called photosynthesis - those “C” carbon atoms, over time, become the "wood" that is the tree. So while the bonfire alone isn't carbon neutral, in the relatively short lifespan of the tree, the growth-to-bonfire process is carbon neutral. And if you didn't burn it, as the tree decomposed over time in your backyard or in a landfill or as mulch, it would release the same CO2 back into the atmosphere.

Compare that to burning fossil fuels, which prior to combustion were sequestered deep underground, and would have stayed there if not for their extraction. One could say that over the time horizon of millions of years it took the oil to form to when it was ultimately burned, that too is carbon neutral! But over the few hundred years that we have existed as an industrial society, however, this is not carbon neutral. That additional carbon sits contributes to global warming (or gets absorbed by the ocean, acidifying the water, or having other deleterious effects on our global environment).

Is this the Final Word?

Wood is better than many alternative materials. And at least from a carbon neutrality perspective - though not from a localized air pollution or a deforestation perspective in certain regions - wood is an acceptable fuel. But that’s not to say we can cut down all the trees: cutting down one tree from a forest is different from harvesting the entire forest!

Indeed, there’s a lot more to responsible harvesting for forest management. Entire organizations exist to help manage, educate, police, and certify producers. And - spoiler alert! - it has nothing to do with “raking the forests” of leaves, as Trump ignorantly claimed in a recent conversation. Trees - like animals, and ecosystems in general - can also become endangered or at risk. All of these will be topics I cover in future posts.

Is there a particular environmental concern you have with forestry management, or consuming wood products? Email me or leave a comment - I’d love to hear your thoughts.