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Guardian Structural Technologies

ASTM C203

Standard Test Methods for Breaking Load and Flexural Properties of Block-Type Thermal Insulation

What it measures

Bends a block of insulation until it breaks, reporting the breaking load and flexural strength.

Why it matters for a panel envelope

An insulation core that is also a structural web has to resist bending, not just conduct little heat. This is the test for that property.

Guardian Shield™

Cited in the Shield™ specification's reference standards for the EPS core.

Source · 3-Part Specification, 1.3 F.7 · Guardian documents

Written by Data Subsystems, for Guardian Structural Technologies. Last updated .

Drafted from Guardian Structural product literature and published building-science sources. Awaiting Guardian technical review. Confirm any figure against the current product documents or ask us before you rely on it in a design.

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