What Happens to Construction Waste After Collection? A Material-by-Material Guide

Construction projects generate a wide range of waste materials — from timber and metals to plastics, aggregates and soils. But what actually happens once a skip leaves site?

Understanding the journey of construction waste after collection is increasingly important for contractors, developers and site managers. It supports compliance, helps manage costs, and plays a role in meeting sustainability expectations.

This guide explains how common construction waste streams are handled after collection — and how correct segregation on site helps maximise recovery.

Why Construction Waste Journeys Matter

Once waste leaves site, it doesn’t follow a single path. Different materials require different treatment routes, specialist facilities and handling processes.

The quality of segregation at source has a direct impact on:

• Recovery potential

• Recycling options

• Compliance with waste regulations

• Overall waste management costs

By understanding these journeys, construction businesses can make more informed decisions about how waste is managed.

Timber Waste: From Site to Recovery

Timber waste is one of the most common materials generated on construction sites.

After collection:

• Wood is inspected and segregated by grade

• Clean timber is processed through shredding or chipping

• Depending on quality, it may be sent for reuse, OSB product or energy recovery

Contamination with plasterboard, plastics or general waste can limit recovery options, which is why segregation on site is strongly recommended.

Plastics: Sorting and Reprocessing

Plastic waste from construction sites includes packaging, sheeting, piping and containers.

After collection:

• Plastics are sorted by polymer type

• Materials are cleaned and baled

• Bales are sent to specialist reprocessors

Correct segregation reduces contamination and improves the likelihood that plastics can be reprocessed into new products.

Aggregates & Hardcore: Crushing for Reuse

Concrete, bricks and hardcore can often be recovered and reused.

After collection:

• Materials are crushed and screened

• Graded recycled aggregates are produced

• Recycled material can be reused in construction applications, subject to specification

Using recycled aggregates can help reduce reliance on virgin materials and supports more resource-efficient builds.

Metal Waste: Closed-Loop Recycling

Metals are one of the most valuable recyclable construction materials.

After collection:

• Ferrous and non-ferrous metals are separated

• Materials are processed and sent to smelters

• Recycled metal is used to manufacture new products

Because metals can be recycled repeatedly without losing quality, correct segregation is particularly important.

Mixed Construction Waste: Sorting After Collection

Where segregation on site is not possible, mixed construction waste can still be processed.

After collection:

• Loads are mechanically and manually sorted

• Materials such as wood, metal, aggregates and plastics are separated

• Each stream follows the most appropriate recovery route

However, segregation at source remains best practice and typically delivers better recovery outcomes.

Plasterboard: A Specialist Waste Stream

Plasterboard requires careful handling.

After collection:

• Plasterboard must be kept separate from biodegradable waste

• Gypsum is recovered and processed by specialist facilities

• Recovered gypsum can be reused in manufacturing

Incorrect disposal can cause environmental and compliance issues, making segregation essential.

Soil & Stone: Assessment and Recovery

Excavated soil and stone may be suitable for recovery, depending on quality.

After collection:

• Material is assessed and, where required, tested

• Suitable material can be recovered or reused

• Unsuitable material follows compliant disposal routes

Early planning helps identify reuse opportunities and reduce unnecessary disposal.

How Segregation Improves Outcomes

Across all material types, one principle remains consistent:
the better the segregation on site, the better the recovery outcome.

Clear waste streams reduce contamination, increase recycling potential and help control costs.

Choosing the Right Waste Partner

A waste management partner should offer more than collections alone. Understanding material journeys, compliance requirements and recovery options is essential for modern construction projects.

At Hamilton Waste, material recovery is considered at every stage — from collection planning through to processing and onward movement.