Types of hazardous waste in the construction industry and how to manage them

The construction industry is one of the largest producers of waste in the UK, generating around 62% of total national waste (DEFRA). While much of this waste can be recovered or recycled, a significant portion is classified as hazardous waste — materials that pose a risk to human health, wildlife, and the environment if not managed correctly.

Understanding the types of hazardous waste commonly found on construction sites is critical for compliance, safety, and sustainability. This blog explores what hazardous waste is, provides examples from construction, highlights recycling and treatment methods, and explains how adopting a circular economy approach can reduce risks and create value.

What is hazardous waste?

According to the UK Government, hazardous waste is any waste that contains substances or properties that make it harmful to human health or the environment (Gov.uk). Unlike general construction waste such as rubble or timber, hazardous waste requires specialist handling, storage, transport, and disposal.

The Hazardous Waste Regulations 2005 set out strict guidelines for classification, segregation, and treatment. Businesses that produce or manage hazardous waste must:

• Classify it correctly using the List of Waste (LoW) codes.

• Keep it separate from non-hazardous waste.

• Use licensed contractors for collection and disposal.

• Complete consignment notes for transport.

Partnering with experts like Reconomy, which specialises in hazardous waste management, ensures compliance while supporting sustainability goals.

Why hazardous waste matters in construction

The construction sector is particularly high-risk because it frequently deals with hazardous substances in both new builds and brownfield remediation projects. Left unmanaged, hazardous waste can:

• Contaminate soil and water supplies, impacting local ecosystems.

• Release toxic air pollutants during demolition or burning.

• Endanger workers and the public, causing illness or injury.

• Lead to legal penalties, including fines and reputational damage.

The UK’s Environment Act 2021 introduced targets to reduce avoidable waste by 2050 and restrict the export of waste to non-OECD countries. This encourages the construction industry to find sustainable ways to deal with hazardous materials, making compliant waste management more important than ever.

Types of hazardous waste in construction

Hazardous waste is not a single category but includes many materials, each requiring unique handling. Below are some of the most common types of hazardous waste found in construction.

1. Solvents (Volatile Organic Compounds, VOCs)

Solvents are widely used for cleaning, thinning paints, or dissolving substances. Many contain volatile organic compounds (VOCs) such as dichloromethane (DCM), which can be harmful when inhaled.

• Risks: Air pollution, health hazards for workers, and contamination if released into water or soil.

• Regulations: Controlled under the Hazardous Waste Regulations and REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals).

• Management: Solvent waste should be stored in sealed containers and can often be treated through solvent distillation to recover reusable material.

2. Asbestos

Once a popular building material for insulation and fireproofing, asbestos was banned in the UK in 1999. However, it is still found in many buildings constructed before 2000.

• Risks: Inhalation of asbestos fibres can cause mesothelioma, lung cancer, and asbestosis.

• Regulations: The Control of Asbestos Regulations 2012 govern handling and disposal.

• Management: Removal must be carried out by licensed contractors. Reconomy offers safe, compliant hazardous waste management solutions for asbestos.

3. Polychlorinated Biphenyls (PCBs)

PCBs were widely used in electrical equipment such as transformers and capacitors. Though banned, some equipment containing small amounts of PCBs is still in use until 2025.

• Risks: PCBs persist in the environment, accumulate in food chains, and are linked to cancer in animals and humans.

• Regulations: UK law requires safe disposal of any equipment containing PCBs by 2025.

• Management: Collection and specialist treatment through high-temperature incineration or chemical dechlorination.

4. Paints, adhesives, and resins

Many paints and adhesives contain solvents, heavy metals, or other toxic substances. Even empty containers are classed as hazardous waste.

• Risks: Soil and water contamination if disposed of incorrectly.

• Management: Use dedicated collection services and explore recycling through solvent recovery or repurposing.

5. Contaminated soils

Brownfield sites often contain soils contaminated with hydrocarbons, heavy metals, or other toxins.

• Risks: Spreading contamination during excavation.

• Management: Soil washing, stabilisation, or safe disposal via licensed facilities.

6. Batteries and electrical waste (WEEE)

Construction often involves equipment powered by batteries and generators. These may contain lead, mercury, cadmium, or lithium.

• Risks: Fire hazards, groundwater contamination, and air pollution.

• Regulations: Covered by the Waste Electrical and Electronic Equipment (WEEE) Directive.

• Management: Collection through authorised WEEE and battery recycling streams.

Recycling and treatment of hazardous waste

The good news is that many types of hazardous waste can be recycled or treated, reducing the burden on landfill and recovering valuable resources.

Water treatment

Used for liquid hazardous waste such as oily water, acids, and paint residues. Treatment removes contaminants, allowing water to be reused safely in industrial processes.

Solvent distillation

Waste solvents can be distilled to separate hazardous vapours from non-toxic substances. The recovered solvent is then reused in industry, reducing the need for virgin materials.

Stabilisation and solidification

Hazardous materials can be mixed with binding agents to immobilise toxins. This reduces the risk of leaching into soil and groundwater.

Thermal treatment and incineration

Some hazardous wastes, such as PCBs or medical waste, require high-temperature incineration to ensure complete destruction of harmful compounds.

Recycling metals and aggregates

Contaminated metals can often be recovered and reprocessed, while aggregates can be washed and reused where safe.

The circular economy and hazardous waste

Traditional approaches to hazardous waste focus on safe disposal. However, a circular economy approach aims to design out hazardous substances, keep materials in use for longer, and regenerate natural systems (Ellen MacArthur Foundation).

In construction, this means:

• Substituting hazardous materials with safer alternatives.

• Designing buildings for disassembly and reuse.

• Recycling solvents, metals, and contaminated soils wherever possible.

• Partnering with sustainable providers like Reconomy, whose waste management services help clients adopt circular principles.

By prioritising circular solutions, businesses not only comply with legislation but also reduce costs, enhance sustainability credentials, and protect communities.