Work

Leaching Assessment of Non-Metal Roofs – Comparison of Field Studies and Laboratory Leaching Tests

Year: 2026

Type: article

Abstract: Building products, like non-metal roofing materials, can contribute pollutants to stormwater. Laboratory leaching tests, particularly the dynamic surface leaching test (DSLT), are employed to evaluate the substance release, but are not designed to simulate field conditions. By comparing results from a DSLT and a 6-month field study for the same materials (clay tiles, concrete tiles, fiber cement sheets, bitumen shingles, treated wood shingles, and plastic tiles) and same analyzed inorganic and organic parameters we provided a basis for interpreting and translating the DSLT outcome to real weather conditions. The objective was to evaluate the reliability of the DSLT in predicting which parameter types are leached from non-metal roofing materials in the field, as well as its suitability for estimating the corresponding concentration levels. The comparison demonstrated that the DSLT reliably predicted more than 80% of pollutants released under environmental conditions, supporting its use for investigating new roofing materials or emerging pollutants to identify parameters contributing to stormwater pollution. Our results serve as a database for interpreting DSLT results and for developing and calibrating transfer models. However, no general pattern was observed between laboratory and field results: for fiber cement, clay and concrete tiles, the DSLT overestimated the concentrations; median concentrations exceeded those in the field, with factors of 2.6 to 115. For bitumen and wood shingles, the DSLT rather underestimated the substance release, resulting in median field concentrations that exceeded those in the laboratory by factors of 1.3 to 10.4. Consequently, transfer models must account for different surface properties of the materials. • Comparison of laboratory (DSLT) and field tests on the leaching behavior of roofing materials. • DSLT reliably predicts substances released at environmentally relevant concentrations. • No general pattern identified to estimate field concentrations using the DSLT. • Fiber cement sheets, clay and concrete tiles released more substances in the DSLT. • Bitumen and treated wood shingles released more substances in the field test.

Source: Journal of Environmental Management

DOI: 10.1016/j.jenvman.2026.129094

Authors: Julia Udvary, Regina Schwerd, Brigitte Helmreich

Institutions: Technical University of Munich, Fraunhofer Institute for Building Physics

Language: English

Topic: Urban Stormwater Management Solutions

Subfield: Environmental Engineering

Field: Environmental Science

Domain: Physical Sciences

SDGs: Clean water and sanitation, Sustainable cities and communities

Open Access status: hybrid

Estimated APC paid: $3,750