If you walk past construction sites and demolition sites throughout the US, you’ll see industrial dumpsters. You will also notice that most construction crews are discarding scrap lumber into dumpsters. The vast majority of construction debris from commercial and residential construction sites throughout the US is sent to landfills. Except for plywood and particle board, all woods can be recycled into numerous products and materials. Every year, the construction industry sends many millions of tons of scrap wood from construction sites and from demolitions to landfills.
The technologies which are involved in recycling scrap lumber have been well understood for approximately 100 years, but few contractors recycle scrap lumber because it is not cost-effective for them to do so. Recycling scrap wood from the construction industry would contribute to slowing the pace of deforestation globally because there would be less need to harvest many thousands of square miles of forests throughout the world because scrap lumber could be providing the exact same materials that come from newly harvested trees.
While the EPA in the US does post data on their website which details how much of the scrap wood which is discarded from household materials such as furniture, cabinets and shipping pallets annually is sent to landfills and how much wood from household sources is recycled, as I researched this article, I found that the EPA does not keep comparable data about scrap lumber from the construction industry. None of the agencies or trade organizations that are involved with the construction industry in the US attempt to monitor the amount of scrap wood which is sent from dumpsters at construction sites and from demolition sites to landfills, so there are no reliable figures for me to cite regarding estimates of the tonnage of wood from different species of trees which is sent from residential as well as commercial construction sites and demolitions throughout the US into landfills every year.
Why is most of the scrap lumber in the US not recycled?
Unless a contractor is LEED certified, almost all contractors presently opt not to attempt to recycle scrap lumber because the process is time-consuming and it is not cost-effective. Contractors would have to separate scrap lumber from all of the other scrap materials that they’re discarding, and then there’s usually no value for the scrap lumber from construction projects because there are presently only a relatively small number of companies throughout the US that reuse scrap lumber from construction projects and from demolition sites.
What does the process involve?
For scrap lumber to be recycled, the layers of paint, primers, varnishes, weatherproofing, stains, and polishes need to be stripped off. All nails, screws, and staples also need to be removed. This is an expensive and time-consuming process, but the technologies which are involved for this have in fact existed for at least a century now.
The process of collecting scrap lumber can be impressively simple. If contractors were to keep separate dumpsters at construction sites designated specifically for scrap lumber, then it would be straightforward for trucking companies to bring dumpsters containing scrap lumber from construction sites directly to companies that process scrap wood for use in other materials. There would be no need to separate scrap lumber from other construction debris because the scrap lumber will have already been stored in separate dumpsters at construction sites and demolition sites.
Once scrap wood arrives at facilities that process it, the removal of the layers of primers, paints, and varnishes can be accomplished almost entirely by industrial sanders, which can be operated either remotely or manually. Metal detectors and magnets can be used to detect all of the nails, screws, staples and fasteners inserted into pieces of wood, and most of the metal fasteners can be removed by machines. Only a small percentage of the process of stripping paint and varnishes as well as removing nails and screws, would need to be accomplished manually.
The technologies do also exist for checking to verify that all of the layers of paint and varnishes as well as all of the nails, screws and other pieces of metal have been removed from wood which has sent from construction sites to recycling facilities before the scrap lumber is sent for reprocessing into new materials.
Although there are some companies that make furniture and decorative items from wood which has been salvaged from buildings that have been demolished and from shipping pallets, this is presently done only on a small scale. There are no almost no companies in the US that recycle scrap wood from construction sites into most of the products which scrap lumber could potentially be used for manufacturing.
What products can scrap lumber be recycled into?
Once all of the paint and varnishes as well as pieces of metal, have been removed from lumber, wood which had come from construction sites and from demolitions can potentially be shredded into wood chips which can be used as a surface material for covering pedestrian footpaths, as animal bedding and wood chips can also be used as garden mulch.
Scrap lumber can also potentially be recycled into the source material which could be used in the manufacturing of many kinds of paper products and cardboard.
Scrap lumber can also be shredded and used as a feedstock material for manufacturing at least three kinds of biofuels. Scrap lumber is almost always going to include woods that had been harvested from several different species of trees. All wood contains cellulose, so shredded chips from wood from construction sites could always be used to manufacture biomethane. Wood which had originally been harvested from many species of trees also contains a sugar called xylose in them, so scrap lumber from the species which contain significant quantities of xylose in them can be shredded into wood chips which can be used for the manufacturing of bioethanol and biomethanol. Using woodchips for producing biofuels is not nearly as efficient as the process of manufacturing biofuels from food scraps and other organic waste materials, but it is a notably more productive use of scrap lumber than sending it to landfills.
Large pieces of scrap lumber can easily be sliced into smaller pieces of wood which can be sent to lumber mills and to hardware stores for sale for use in carpentry projects.
Once all of the paints and varnishes, as well as the metal fasteners, have been removed from scrap lumber, wood sourced from construction sites can also safely be used as firewood.
Wood can also be further shredded into sawdust, and sawdust can be used as a garden mulch for growing fruits, vegetables, and flowers, and it can also be used as a substrate for growing many species of mushrooms.
It is important to note that it is only safe to use scrap wood for manufacturing the products that I’ve mentioned if it can be verified that 100% of the paints and varnishes which had been applied onto the wood is removed and if 100% of the metal fasteners which had been inserted into the wood have been removed. The technologies to create machines that could scan wood to verify that all of these items have been successfully removed from pieces of wood do exist, and these technologies are well understood, but these technologies are expensive.
If laws were proposed which would require that lumber mills use environmentally friendly glues when they assemble plywood and particle board, then plywood and particle board could be recyclable too.
What Are LEED Standards?
In 1993 The U.S. Green Building Council and the Natural Resources Defense Council proposed creating standards for environmentally friendly construction methods, which led to the creation of Leadership in Energy and Environmental Design (LEED) certification. LEED certification is now used in numerous countries worldwide as the standard for incorporating green technologies within the construction industry.
As new technologies are created, The U.S. Green Building Council periodically reviews and updates the standards for LEED certification so that the latest technologies which relate to environmentally friendly construction are included within LEED certification.
Contractors who are LEED certified will be familiar with the technologies involved in recycling and contractors who are LEED certified will make a very reasonable effort to recycle as many materials as possible from the construction projects and demolition sites on.
While the number of contractors in the US who are LEED-certified is slowly increasing, the vast majority of contractors throughout the US are not LEED certified. The vast majority of contractors throughout the US do not seem to be interested in becoming LEED certified anytime within the course of the 2020s.
Why is this issue understudied?
The issue of recycling scrap lumber is not being entirely ignored, but it is rarely studied and it is not widely publicized either in the mainstream media in the US or in trade publications within the construction industry. I suspect that the primary reason that the issue is rarely studied simply because there are presently no systems in place anywhere in the US or in any other countries that would make it cost-effective for most contractors to recycle scrap lumber from construction sites on an industrial scale.
The paints, varnishes, polishes, and glues that have been used on wood will gradually break down. The paints and varnishes do contaminate the soil as well as the groundwater in the landfills that scrap lumber is sent to. Still, scrap lumber that has been sent to landfills is a relatively minor source of pollution when compared to many other materials which are legally routinely sent to landfills throughout the US every day. The wood itself is pretty harmless; aside from the paint and varnishes which are on the outermost layers of wood, the process of decomposition of wood that has been discarded from construction sites is chemically essentially the same process as the process of decomposition that occurs when a tree falls in a forested area, which is a very natural process.
When materials that do not cause large-scale pollution are sent to landfills, few people in any industry agency will usually study the long-term effects of sending those materials into landfills.
This issue was not mentioned at all at the 27th annual United Nations Climate Change Conference in Sharm El Sheikh, even though it is directly related to a number of issues that were addressed at the annual climate change conference. The delegates to the COP 2022/ COP27 conference discussed reforestation, biodiversity, decarbonization and plant-based food and energy sources. Still, none of them mentioned proposing legislation that would encourage contractors to recycle scrap lumber from construction projects or encourage entrepreneurs to open companies that would shred scrap lumber and process shredded woodchips which would result from scrap lumber into new materials.
How can this work?
There are a number of ways that the issue of recycling scrap lumber can be effectively addressed. There are numerous Federal and state agencies that can study this issue. If the Federal government, as well as state governments, were to offer tax credits to contractors who would provide documentation that would verify that they’re recycling scrap lumber from the projects that they’re working on and if the Federal government and state governments throughout the US were to offer tax incentives to people who are interested in opening companies which would shred scrap lumber that they receive from contractors and subsequently process the shredded woodchips into new materials, then scrap lumber recycling would become far more commonplace.
Deforestation and Reforestation
The UN Population Division’s current predictions are that the current population of the world will reach 9 billion people before the year 2040 and that the population of the world will exceed 10 billion people before the year 2060. While it is becoming increasingly common for some contractors to opt to use steel as their material of choice for use in assembling beams in residential homes because some of the kinds of industrial steel that are used in the construction industry are becoming less expensive, the demand for lumber products is still continuing to rise.
And while plastics are very common materials for use in packaging products, the demand for cardboard is continuing to rise, and while it is becoming increasingly common for many industries to go paperless, the global demand for paper products is also still rising.
The source materials for all of the aforementioned products will be coming either from legal sources or from illicit black market sources.
In a world in which government agencies throughout the world now need to concentrate on researching attempting to prevent the next pandemic or terrorist attacks and how to prepare in response for disasters, governments simply do not possess the personnel which would be needed to monitor all of the forests within their countries to attempt to ensure that no illegal logging is occurring. And there’s no shortage of lumber mills in many countries which are willing to accept logs that have been illegally harvested, and government agencies in most countries are too understaffed to be able to effectively monitor lumber mills to ensure that all of the wood which they are accepting into their facilities for processing has been harvested legally.
As long as it is potentially profitable, people will continue to harvest trees illegally throughout the world every year.
Because scrap lumber is essentially free insofar as most contractors view it as valueless and discard it in their dumpsters and it will subsequently be sent to landfills, collecting it for recycling is quite probably more cost effective than illegal logging. Scrap lumber could provide the source materials for many products, which presently come from a combination of lumber which has been legally harvested and lumber which comes from questionable origins.
During the summers of 2020, 2021 and 2022, there were severe droughts throughout North America. In the summer of 2022, the most severe drought in Europe since the middle of the 16th century occurred in many of the countries in Europe.
The recent droughts resulted in trees throughout many woodland areas and forests throughout Europe dying, and wildfires occurred in the western states in the US on an unprecedented scale. While biologists and climatologists throughout the world are still analyzing the extent to which various industrial practices have contributed to the recent severe droughts, it is quite clear that we can no longer afford to be reckless with any resources which relate to reforestation anywhere in the world.
What can we do about this issue?
If it makes more sense for scrap lumber to be reprocessed into source materials, write to your politicians and candidates running for offices where you live. The only way that politicians will ever begin to discuss proposing legislation which would create tax incentives for contractors to recycle scrap lumber and for people to open companies that would process scrap lumber which comes from construction sites into new materials is if politicians learn that this issue is important to people who live in as well as vote within their constituencies.
Wherever you live, the way to attract attention to this issue is to let your politicians and candidates running for office know that this is an issue that is important to you. When enough people let politicians and candidates know that various environmental issues are important to them, politicians begin to discuss the problems. They begin to propose legislation that is intended to address these issues effectively.