United States & Canada - EN

Use of cullet to reduce raw materials and energy consumption

logo Guardian
What's your challenge?
Design with glass

From anti-reflection to color tints, modern glass enhances design in many ways.

Build with glass

Whatever the construction challenge, we have the glass to help meet it.

Glass for your home

See how the correct choice of glass can help transform a home – and even our wellbeing.

Highlights
7 St. Thomas

Curved glass contributes to harmony between Victorian and contemporary design

Midlands Technical College Library

When glass helps to create a comfortable learning environment

ARO - 242 West 53rd Street

Floor to ceiling windows provide light, transparency and sweeping views of Central Park

Discover our showcase projects, captured through the lens of professional photography.

Explore Guardian Glass projects in your area and beyond with Google Street View and be inspired by the possibilities.

Highlights
Our story

Just as we were in 1932, we're ready to meet the challenges of now and the future

Environmental Stewardship

Find out more about how glass can support sustainable design

Quality control

We strive for quality in everything we do

Use of cullet to help reduce raw materials & energy consumption

Glass Placeholder

We are dedicated to enhancing the energy efficiency of our manufacturing processes and minimizing our resource consumption. One approach to accomplishing these objectives is to maximize the use of cullet – broken or rejected glass – in the float glass production.

The use of 1 ton of cullet saves approximately 1.2 tons of virgin raw materials such as sand, dolomite, soda ash and limestone.

Using cullet also reduces process-related emissions. As it has already undergone the mineralization process, it releases fewer greenhouse gas emissions during melting than virgin raw materials. Every ton of cullet used allows to avoid the need for 2 million BTUs (586 kWh) of natural gas and to reduce up to 700 lbs (318 kgs) of CO2 emissions.

While our efforts may vary across our global fleet, in general, we are working to increase the cullet ratio in our batch by:

  • Optimizing use of internal cullet
  • Sharing best practices across the fleet
  • Testing and implementing new cullet types
  • Maximizing cullet sourcing

Europe

Guardian Glass EU plants achieved an increase in the cullet ratio (broken or rejected glass from internal processes and external sources) in glass from 22% on average in 2019 to 28% cullet on average in 2023

Collecting glass cullet from our customers: when we deliver glass, bins containing customer cullet can be returned in the same trip, therefore helping decrease road traffic and the associated carbon emissions when compared to collecting this cullet via separate, standalone trips.

Glass warehouse placeholder

Logiform

North America

In 2023, the plant in Carleton, MI experimented with making Guardian PrivaGuard™ glass using 70% cullet as percentage of batch weight, and Guardian Clear glass using 100% cullet as percentage of batch weight.