Home / News / Duo Group: UK Specialists in Quarrying, Aggregates, Earthworks, Remediation, Civil Engineering & Infrastructure

What makes us different?

29 April 2026

When contractors, developers and operators across the UK need a partner who can handle the full scope of a complex project — from ground remediation and bulk earthworks to processing plant design, civil infrastructure and long-term maintenance — they call Duo Group. With roots going back to 1981 and a workforce that has delivered some of the most demanding construction and quarrying programmes in the country, Duo Group has earned its position as one of the UK’s most capable and fully integrated solutions providers.

This is not a company that does one thing. Duo Group operates across quarrying, aggregates, brownfield remediation, civil engineering, rail infrastructure, industrial land regeneration, material processing, equipment supply, and specialist fabrication — all under one roof, with a single point of accountability.

A Proven Track Record Across the UK’s Most Demanding Projects

Duo Group’s credentials are not theoretical. They are built on a body of delivered work that spans some of the most technically challenging and nationally significant construction programmes the UK has seen.

HS2 — Washwood Heath, Birmingham Duo Group played a central role in one of HS2’s largest and most complex construction sites: the 65-hectare Washwood Heath depot and Network Integrated Control Centre in Birmingham. Working as a specialist subcontractor to Balfour Beatty VINCI (BBV), Duo Group led the ground remediation and earthworks programme on what was a heavily contaminated former railway marshalling yard — a site with more than a century of industrial history baked into its soil.

The scope was extraordinary: over 1.4 million cubic metres of material excavated and remediated, 1.1 million cubic metres cement-stabilised to HS2 specification, and 1.3 million cubic metres compacted to the required standard. Contaminated soils — including hydrocarbons and asbestos — were carefully managed, a 300-metre watercourse diversion was engineered and delivered with full environmental mitigation, and the deep excavation at the Bromford Tunnel portal (reaching 22 metres below ground level) was completed to allow the two 1,600-tonne tunnel boring machines to break through on schedule. The entire programme was delivered without delays into the TBM stage.

Duo Group’s involvement was independently reported by HS2 Ltd, New Civil Engineer, Balfour Beatty, and Balfour Beatty VINCI — making Washwood Heath one of the most publicly documented demonstrations of Duo’s civil and remediation capability anywhere in the industry.

What Duo Group Does: Five Integrated Divisions

Duo Group’s strength is the combination of its divisions. Rather than being a single-trade contractor, the group brings together specialists across every phase of a project lifecycle — and they work as a unified team.

Duo Turnkey — EPC Plant Design & Build

Duo Turnkey delivers full Engineering, Procurement and Construction (EPC) solutions for material processing plants. For quarry operators, aggregate producers, recycling facilities, and industrial processing clients, Turnkey manages the entire delivery — from initial feasibility and plant design through procurement, civil foundations, structural steelwork, mechanical installation, and electrical commissioning.

The division’s single-point-of-responsibility model is what separates it from the fragmented alternative of appointing separate designers, civil contractors, equipment suppliers, and electrical engineers. Duo Turnkey manages every trade, every interface, and every risk — and the client receives a commissioned, performing plant at the end of it.

Duo Turnkey integrates equipment from exclusive OEM partnerships including Metso, Terex Washing Systems, Telestack and Keestrack — meaning the plant is engineered around world-class equipment that Duo’s own team knows intimately, rather than bolted together from whoever is cheapest on the day.

Typical applications include: hard rock crushing and screening plants, aggregate washing and classification systems, sand and gravel processing, recycled aggregate processing, waste-to-energy feed preparation, and bespoke industrial material handling.

Duo Construction — Civil Engineering & Infrastructure

Duo Construction is the civil engineering and infrastructure delivery division, operating across earthworks, remediation, drainage, highways, reinforced concrete, flood protection, and enabling works for major UK projects.

The division works directly with Tier 1 contractors, joint ventures, developers, and public sector clients — and its project record includes nationally significant programmes such as HS2, major motorway upgrades, port development, and large-scale industrial land regeneration.

Brownfield remediation is a core specialism. Duo Construction has demonstrated at Washwood Heath and at Tees Advanced Manufacturing Park that it can manage contaminated land at multi-million cubic metre scale — including hydrocarbons, asbestos, and legacy industrial pollutants — to the environmental standards required by today’s planning and regulatory frameworks.

Earthworks and ground improvement is where Duo Construction earns its reputation. The team has stabilised, compacted, cut and filled in conditions that range from highly contaminated post-industrial sites to live infrastructure corridors where a single programme delay carries enormous commercial and reputational consequences.

Early Contractor Involvement (ECI) is an approach Duo Construction actively promotes — working with clients during design and pre-construction phases to identify programme risks, optimise material reuse strategies, and build the value engineering into the project before ground is broken rather than after.

Duo Processing — Material Recovery & Contract Processing

Duo Processing provides complete operations management and plant equipment hire for wet and dry material processing, operating on a fixed-price-per-tonne model that gives clients financial predictability across the life of a contract.

For quarry operators, this means predictable unit costs regardless of volume fluctuation, advanced material analysis to maximise extraction yield, and operations management expertise that drives efficiency without requiring the client to carry the overhead of a large internal team. For developers and infrastructure clients, it means excavated material can be processed and recovered on site — turning what would otherwise be a disposal cost into a saleable or reusable product.

The division also integrates waste-to-energy recovery and actively works to reduce landfill dependency across the operations it manages.

Duo Site Services — Plant Maintenance & Rapid Response

Duo Site Services keeps operations running. The division provides planned preventative maintenance, emergency breakdown response, mobile and static machinery repairs, structural repairs, safety inspections, and full lifecycle plant management for clients across the quarrying, aggregates, and processing sectors.

With nationwide field teams of highly skilled, multi-sector engineers, Duo Site Services operates as a proactive partner — building maintenance programmes that protect asset value, extend equipment lifespans, and target measurable uptime outcomes. The division’s approach of refurbishing rather than replacing plant and machinery is both commercially and environmentally sound: extending the working life of heavy equipment reduces capital expenditure and carbon footprint simultaneously.

Capital Sales & Aftermarket — World-Leading Equipment Supply

Duo Group is an authorised and exclusive distributor for four of the most respected names in the global aggregates, quarrying, and material handling equipment market:

Metso — world-leading crushing and screening solutions
Terex Washing Systems (TWS) — advanced wet processing and water management for aggregates, sands, and recycling
Telestack — high-efficiency mobile bulk handling for quarries, ports, and terminals
Keestrack — mobile crushing and screening equipment

This means clients can source, commission, and maintain world-class capital equipment through a single UK partner, with UK-based spare and wear parts inventory offering next-day delivery, full lifecycle service contracts, and technical training from engineers who know these machines in depth.

Industries served include aggregates, quarrying, mining, ports and terminals, recycling and waste management, cement, and power generation.

Engineering Services — In-House Fabrication & Specialist Design

Duo Engineering Services operates from a state-of-the-art 25,000m² fabrication facility in Stoke, equipped with a 19-tonne overhead lifting capacity, CNC cutting technology, and an in-house spray shop. This is a genuine in-house capability — not an outsourced function — which means faster lead times, tighter quality control, and the ability to produce genuinely bespoke structural and mechanical solutions that are integrated directly into Duo Turnkey plant projects.

Services include precision structural steelwork, mechanical installation, plant refurbishment, custom access platforms and walkways, surface treatments and coatings, electrical design and automation, and NDT (Non-Destructive Testing) certified quality assurance.

Sectors & Search Terms: Where Duo Group Operates

Duo Group’s capabilities span a wide range of sectors and project types. If you have found this page through any of the following searches, you are in the right place:

Quarrying and aggregates — Duo Group has operated in the quarrying and aggregates sector since 1981. From plant design and build through to contract processing, equipment supply, and site maintenance, the group supports quarry operators across the full operational lifecycle.

Brownfield remediation and redevelopment — Duo Construction’s brownfield remediation capability is demonstrated at the highest level through its work on HS2’s Washwood Heath site and the Tees Advanced Manufacturing Park. The team manages contaminated land, ground improvement, and enabling works to prepare brownfield sites for their next phase of development.

Earthworks and bulk excavation — Duo has managed multi-million cubic metre earthworks packages across HS2, port development, quarry restoration, and industrial regeneration projects. The team uses GPS machine control, telematic data from plant, and weekly land surveys to verify volume movements and contour accuracy.

Ground remediation and contaminated land — managing contaminated soils including hydrocarbons, asbestos, and other legacy industrial pollutants is a core Duo Construction competency, underpinned by rigorous environmental compliance frameworks.

Civil engineering and infrastructure — roads, rail, drainage, utilities, flood protection, reinforced concrete structures, and ground stabilisation are all within Duo Construction’s scope, as demonstrated across its project portfolio from Scotland to the south of England.

Rail infrastructure and HS2 — Duo Group has been embedded in the HS2 programme across multiple sites and with multiple Tier 1 joint ventures, including Balfour Beatty VINCI and Skanska Costain Strabag. This rail infrastructure track record is relevant to any contractor or developer working within the rail sector.

Industrial land regeneration — projects like the Tees Advanced Manufacturing Park and Washwood Heath show Duo’s ability to operate within large, complex regeneration programmes where multiple parties, regulatory frameworks, and phased delivery requirements must be managed simultaneously.

Aggregate processing and crushing and screening — Duo provides plant design, build, and operations for aggregate processing across hard rock, sand and gravel, and recycled materials, supported by exclusive OEM partnerships with Metso, Terex, Telestack and Keestrack.

Quarry restoration and aftercare — as demonstrated at CEMEX Hatfield, Duo Construction has the capability and the equipment to carry out precision quarry restoration earthworks, including GPS-controlled contouring, drainage installation, and soil layer placement to meet restoration licence conditions.

C&D waste recycling and material recovery — the Duo Processing division operates across construction and demolition waste recycling applications, recovering value from arisings that would otherwise go to landfill.

Motorway and highways works — Duo Construction has delivered highway and motorway improvement works including the Glasgow motorway improvements project, demonstrating capability within the road infrastructure sector.

Port and marine infrastructure — the London Gateway surcharge placement project demonstrates Duo’s ability to operate within demanding port and marine infrastructure environments.

Tunnel arisings management — managing the treatment, classification, and placement of material arising from tunnelling operations is a specialist skill that Duo Construction has deployed on the HS2 programme for the Skanska Costain Strabag joint venture.

Why Contractors and Developers Choose Duo Group

Single point of responsibility. Appointing Duo Group means one contract, one programme, one accountable team — from initial earthworks through to a commissioned and running plant or a construction-ready handover. This eliminates the coordination risk and the contractual grey areas that arise when multiple specialist subcontractors share a programme.

Scale and proven delivery. A contractor that has delivered 1.4 million cubic metres of earthworks and remediation on HS2 — on time, to specification, and without delays into the TBM programme — has demonstrated the kind of delivery certainty that Tier 1 contractors and infrastructure clients need to see before appointing a specialist subcontractor on a nationally significant project.

In-house capability that reduces supply chain risk. The 25,000m² fabrication facility in Stoke, the exclusive OEM partnerships, and the in-house engineering and design team mean that Duo Group is not dependent on a fragile external supply chain to deliver. Plant components are fabricated, equipment is supplied, and electrical systems are designed and installed by Duo’s own people.

Nationwide coverage. From the Tees Valley to Teesside, from Birmingham to Hertfordshire, from the Thames Estuary to Glasgow — Duo Group has delivered projects the length of Great Britain, with regional teams and the logistics infrastructure to mobilise at scale wherever the work is.

Financial predictability. The fixed-price-per-tonne processing model and long-term lifecycle service contracts remove uncertainty from project economics. For developers managing complex land regeneration programmes or quarry operators planning capital investment cycles, this kind of commercial structure is a genuine differentiator.

Sustainability credentials. Duo Group’s commitment to material reuse, water recycling, reduced landfill dependency, and refurbishment over replacement is embedded in the way every division operates — not as an afterthought but as a core part of the value proposition. On HS2’s Washwood Heath site, the combination of Duo’s work and BBV’s cut-and-fill strategy eliminated the need to import aggregate and avoided an estimated 54,400 vehicle movements on local roads.

About Duo Group

Duo Group is a Coventry-based multi-divisional construction and processing solutions provider with a history dating to 1981. The group operates through five divisions — Duo Turnkey, Duo Construction, Duo Processing, Duo Site Services, and Capital Sales & Aftermarket, supported by an in-house Engineering Services function — and serves clients across quarrying, aggregates, civil infrastructure, rail, ports, industrial land regeneration, and recycling.

The group’s senior leadership team includes Managing Director Martin McWilliams, alongside directors responsible for Turnkey, Processing, Construction, Capital Sales, Finance, Technical, Commercial, Sustainability and Electrical, Engineering, and HSE functions.

Duo Group holds exclusive OEM distribution relationships with Metso, Terex Washing Systems, Telestack and Keestrack in the UK and Ireland, and operates a 25,000m² fabrication facility in Stoke equipped for precision steelwork, plant refurbishment, and specialist structural fabrication.

The company’s motto is simple: There’s always a way.

Get in Touch

Whether you are planning a brownfield remediation programme, tendering a major earthworks package, looking to commission a new aggregate processing plant, or need specialist equipment, maintenance, or civil infrastructure delivered anywhere in the UK — Duo Group has the capability, the track record, and the team to deliver it.

Contact Duo Group today to discuss your project.