Circular solution will tackle construction’s carbon issue
Innovating with a sustainability-focused business model based on recycling construction waste into aggregates, Livingstonbased firm Brewster Brothers is blazing a trail in Scotland by greatly reducing the need for landfill space and natural resources, rev
THE construction sector is a massive contributor to carbon emissions. In Scotland, it is responsible for no less than half of the country's waste and 40 per cent of its CO2 output. In addition, it accounts for half of natural resource consumption. The good news is that improvements are there to be made. However, these require a dramatic change in both thinking and practice. Far too much waste, including potentially valuable soil, is still going to landfill. Yet when it comes to sustainability, it can be part of the solution rather than the problem.
A Scottish company, Livingstonbased Brewster Brothers, is making a positive contribution to the circular economy by taking the by-products of demolition and turning them into recycled aggregates that can be used in new construction projects.
The result is that the material finds a new purpose while at the same time reducing the amount of waste that goes to landfill and the amount of natural resources the industry consumes. In essence, everyone is a winner.
“We largely sell the recycled product back to the same customers, such as civil and utility contractors, who ask us to take it away in the first place”, says Scott Brewster, the company's Managing Director. “They put a large amount in the infrastructure before houses are built.”
This sort of imaginative re-use of resources has never been more necessary.
Last year, it is calculated that there was an increase of 587,000 tonnes going to landfill – a huge rise of more than 22 per cent. The growth in soil dumping was even more dramatic at 297,000 tonnes, or almost 36 per cent.
“As more facilities like ours open, those numbers will decrease”, Scott adds. “There is also a new regulation arriving in 2025 and this bans any biodegradable municipal waste – effectively, that found in black bags. That means a lot of landfills are going to become unviable and are going to shut, with the waste going to incineration instead. This willl free up a lot of waste soil used as daily cover and restoration material for recycling.”
Scott believes that fundamentally, landfill tax is still too low, particularly for soil, which is charged at a lower rate.
“Dumping it should never be cheap. To my mind, it should be cost prohibitive. Evidently, it's still affordable, as many millions of tonnes are still going there.”
At present, recycled aggregates are used for relatively low value civil applications such as cable and pipe bedding and for drainage, paving and some low-grade concrete production.
“We are trying to persuade our customers to use them higher up the value chain. We have seen a steady increase in turnover that has been driven by demand and the tonnages we can produce.
“Since COP26, there's been a growing awareness that these aggregates should be used – civil engineers and quantity surveyors are specifying them more and more.
But it's my belief that their use should be mandatory. Why would we waste such a valuable resource?” In order to keep up with changing demands and expectations, the Scottish construction sector needs to embrace the new principles of circular resource management, he believes.
“There has been a noticeable shift in attitude from our customers since we started in 2017. They are genuinely enthusiastic about fuelling the industry's transition to net zero and are starting to see that they make business sense. They are the ones that are going to make it happen. We are here to help them.”
Brewster Brothers has been involved in consultations over the Circular Economy Bill which made its way through the Scottish parliament over the summer and is currently preparing a response to the Scottish Aggregates Levy consultation.
Soil and rubble in particular is falling through the net and is still going to landfill: it is a valuable resource that could be used for recycling into new products.
“We need to capture all that to ensure that we are making the most of this waste stream. We also need to create more availability – a common complaint from the construction industry about recycled aggregates is that they would like to use more of them, but there's a problem getting hold of them.
“There's a supply issue, but that's not surprising when so much feed material is still going to landfill.”
Soil is a particular issue. This is particularly valuable and can be easily recycled. It contains sand and gravel, creating a circular solution for the construction industry.
Topsoil in particular is a highly useful resource as a carbon sink, Scott says. “It doesn't really need any further processing and it should be re-used.”
Part of the issue, he believes, is that there is still a need to find locations that make use of this, such as gardens and housing sites.
“There really isn't a lot of processing needed, apart from perhaps screening it to make it a better quality product. Subsoils can go through our wash plant and be broken down into their constituent parts of gravel, silt, sand and clay, all of which can then be used. It's more valuable when this is done.”
He describes this kind of recycling as a low hanging fruit. “The technology is there. We are not trying to push the technological boundaries. These are established methods that have been around for decades in the sand and gravel quarrying industry.
“They have just been adapted for recycling in order to clean up a contaminated waste stream. We are not reinventing the wheel. It's innovative in terms of its scale and the application in which it is used, but it really should be just almost second nature.”
No soil, and certainly no rubble, should be going to landfill, he believes.
“The technology exists to ensure that doesn't happen, but we need attitudes and habits to change.”
We largely sell the recycled product back to the same customers such as civil and utility contractors