Wood recycling: How it works, waste grades and why it’s vital to the UK

Wood recycling is an especially important part of the UK’s circular economy due to it being such a scarce resource – and it can actually be one of the easier materials to recycle.

While plastic can be problematic for traditional recycling processes, wood is often readily reusable without much processing.

And when wood can’t be reused, recycling is almost always an option for clean wood, treated wood, and mixed wood – which is quite fortunate, considering the huge lack of UK forestry…

Why wood recycling is so important to the UK

Due to a growing population and heavy wood usage for building naval ships, the UK’s forests were depleted down to just 5% of land coverage in 1990. This grew to 13% by 2020, but is still one of the lowest in Europe.

Without sufficient domestic sources, the UK imports 80% of the wood we use, making the nation the second largest wood importer in the world after China.

The price of raw wood is on the rise, so recovering perfectly good wood to subsidise the cost of construction projects and making it more sustainable at the same time is a win-win for the UK.

MORE: Sustainable building materials: Is this the end of concrete?

Recycling wood diverts wood waste from landfill, conserves natural resources by reducing deforestation, brings down emissions from wood imports and even boosts local economies by creating recycling jobs and new business opportunities.

Whether it comes from construction sites, industrial premises, demolition, manufacturing, packaging (pallets) or households, waste wood is a valuable resource that needs to be properly managed.

But before turning to wood recycling and energy generation, reusing wood is the best place to start getting the most out of it.

‘Our greatest resource’

In the UK, 4.5 million tonnes of waste wood is generated every year, but a lot of it needn’t go to waste at all.

In fact, wood is such a versatile material that it can actually be reused in construction or crafting projects with very little processing involved.

Sarah Barker, Suffolk’s Weird & Wonderful Wood festival organiser, told SunSkips that they can pretty much always find a use for waste wood, turning it into wood chips and shavings. And the raw materials they use also come from local, sustainable sources.

She said, “It’s fantastic that we have people making furniture from local trees that have fallen in the wind so nothing goes to waste.

“There was a tree that had come down in the woods near Bury St Edmunds and this guy had made a beautiful garden bench out of it…

“Wood is our greatest resource. We have a huge debt to the planet and must be responsible with it.”

Reusing wood is a fantastic way to contribute to the circular economy and prevent unnecessary waste. But it’s not always possible, so recycling is the next best step.

The different types of waste wood

Waste wood in the UK is grouped into four classifications:

• Grade A is non-processed, clean wood.
• Grade B is processed wood and composite material.
• Grade C is contaminated wood.
• Grade D is hazardous waste.

Colloquially, waste wood is referred to as clean wood, treated wood, mixed wood and dirty wood.

Grade A (clean wood)

Clean wood is, unsurprisingly, the best wood for recycling due to it being free of contaminants like paint, glue or nails.

It might come from landscaping and tree maintenance, wood pallets used for shipping or off-cuts from the manufacture of untreated wood products.

Clean wood can be easily recycled into new products like animal bedding, mulch, compost, paper, cardboard and chipboard. Because it’s in such good condition, clean wood can also be used to produce new wood products like furniture, flooring and decking.

Grade B (industrial feedstock)

Grade B wood is also quite clean, so also valuable. It often comes from the construction and demolition industry, such as wood used in window frames, or from mixed waste taken to recycling centres.

Once the wood has been separated, it can be used to make panel board, but might also be designated for biomass fuel, depending on the quality.

Grade C (fuel grade)

Wood in the form of chipboard and fibreboard is used to make fuel.

It might have also been mixed with other non-hazardous materials like plastic, metal and glass (which requires a lot more processing to separate the wood) or treated with preservatives and chemicals that make it unsuitable for recycling into certain products.

Grade C wood is best recycled into wood pellets or chips and burned for energy generation.

Grade D (hazardous)

Dark-looking wood treated with creosote or chlorophenolic formulations that give off a chemical or smoky smell is likely hazardous.

Hazardous wood is often found in fencing, railway sleepers and cooling towers.

Grade D wood waste must be collected or taken to a facility licensed to manage hazardous waste.

Recycling wood: the process

While only 2% of the UK’s wood waste was recycled in 1990, the rate skyrocketed to 80% in 2020.

The first step in wood recycling is collection. This might be via a Household Waste Recycling Centre or a local skip hire company like SunSkips.

Once collected, the wood is sorted into categories and any contaminants like nails and screws are removed before it’s chipped into smaller pieces.

Once it’s chipped, it will then be screened to remove any existing contaminants before being further processed according to its grade.

MORE: How glass recycling works: From sorting to new products

Wood used for biomass fuels

For wood waste that’s best suited as an energy source, biomass products like pellets can offer a sustainable alternative to fossil fuels, further protecting the environment through better waste management.

The UK has taken the biomass industry very seriously with significant growth in recent years. In fact, just over half of the UK’s waste wood is designated for energy production as biomass fuel.

MORE: SRF vs RDF: What’s the difference between the alternative fuels?

Wood recycling methods are improving all the time and SunSkips is always looking to the horizon for the latest trends to be as sustainable with its management of wood waste as possible.

SunSkips may be able to offer reduced rates to clients that are able to separate clean wood. Get in touch with our friendly team to discover how SunSkips can help you improve your wood disposal processes.