Projects
Status
Complete
Partners
- Paintback
- Swinburne University of Technology
Outputs
- N. Zhang, A. Xu, J. Sanjayan, P. Rajeev, M.I. Kabir, R. Roberts, Impact and Potential of Reclaimed Water-based Paint in Concrete, J. Build. Eng. 94 (2024) 109822.
- N. Zhang, J. Bai, J. Sanjayan, P. Rajeev, I.M. Kabir, R. Roberts, Air Entrainment, Carbonation and Shrinkage in Concrete containing Reclaimed Water-Based Paint, J. Mater. Civ. Eng. (2025).
- N. Zhang, J. Bai, J. Sanjayan, P. Rajeev, I.M. Kabir, R. Roberts, Mechanisms behind the improved Durability Properties in Concrete by Reclaimed Paint addition, J. Mater. Civ. Eng. (under review).
- N. Zhang, J. Bai, J. Sanjayan, P. Rajeev, I.M. Kabir, R. Roberts, Property Improvements of Concrete Containing Reclaimed Water-Based Paint, 2025 Concrete Conference.
- N. Zhang, J. Bai, J. Sanjayan, P. Rajeev, I.M. Kabir, R. Roberts, Mixture Design Strategies for Air Management in Mortars Incorporating Reclaimed Water-Based Paint, Cement and Concrete Composites (Submission).
- N. Zhang, J. Bai, J. Sanjayan, P. Rajeev, Enhancing Carbonation Resistance of High SCM Concrete with Reclaimed Water-based Paint, Cement and Concrete Composites (Submission).
Videos
Every year, large volumes of paint go to waste, posing environmental risks such as contaminating waterways.
To address this, Australia’s 5 major paint manufacturers established Paintback to recover unused paint and explore ways to repurpose it.
Meanwhile, the concrete construction industry needs to reduce carbon emissions and increase circularity.
While waste products like slag and fly ash can replace cement to produce low-carbon concrete, using them in high volumes compromises durability and limits their practical use.
Researchers from Swinburne University of Technology conducted laboratory testing on concrete mixes with reclaimed waste paint as a liquid additive or a partial water replacement.
They discovered that adding reclaimed paint to concrete mixes with high amounts of slag and fly ash dramatically improved carbonation resistance (durability) while maintaining strength required for a 32 MPa concrete grade—ideal for non-structural applications such as footpaths and pavements.
Researchers produced a comprehensive database of the mechanical properties of paint-modified concretes. They also developed a framework for cost-benefit analysis and conducted a preliminary carbon reduction assessment.
This project has delivered evidence for adding reclaimed paint to low-carbon concrete to improve the durability of non-structural applications.
By extending the service life of structures, a reclaimed paint additive can make low-carbon concrete 40–60% more carbon efficient, delivering roughly twice the service per unit of carbon emitted.
This addresses the durability challenges of concrete with high volumes of slag and fly ash, supporting the construction industry to achieve sustainability targets around carbon emissions and circularity.
By supporting increased volumes of cement replacements, a reclaimed paint additive would help concrete manufacturers lower material costs.
Using reclaimed paint as a partial water replacement also helps preserve water as it becomes an increasingly precious resource.
The database and findings from this project will form the technical basis for Environmental Product Declarations (EPDs) and sustainability certificates for reclaimed paint concrete.
Follow-up research will validate field performance by testing carbonation, permeability, strength retention, and long-term durability.
Paintback is exploring partnerships with ready-mix suppliers to scale up the reclaimed paint additive as a commercial product.
Longer-term research will support standardisation, life-cycle carbon analysis, and compatibility with low-carbon concrete and advanced construction.
