| Core Material and Thermal Conductivity | 15% | Typical declared thermal-conductivity ranges:
EPS: approximately 0.035–0.040 W/m·K
XPS: approximately 0.029–0.036 W/m·K
PUR/PIR: approximately 0.022–0.028 W/m·K | Obtain product datasheets, declared design values, test reports, and the test method used, such as ISO 8301, ISO 10456, or ASTM C518. | Lower thermal conductivity can reduce panel thickness or heating and cooling loads. The declared value should be assessed together with temperature, moisture, and aging conditions. |
| Thermal Aging and Dimensional Stability | 15% | Require documented dimensional-stability testing. For many rigid foam products, a commonly specified dimensional-change limit is approximately ≤2% after conditioning, subject to the applicable product standard. | Review accelerated-aging results, dimensional-change reports, production history, and the supplier’s definition of “non-aging.” Confirm whether the result applies to the complete panel or only the core. | No polymeric foam is completely immune to aging. Thermal resistance may change over time because of gas diffusion, moisture, temperature, and installation conditions. |
| Water Absorption and Moisture Resistance | 12% | Prefer closed-cell cores with documented low water absorption. XPS and PUR/PIR generally provide lower liquid-water absorption than standard EPS, but actual performance depends on density, facers, joints, and test method. | Request water-absorption results under the relevant standard, vapor-permeability data, edge-sealing details, and wet-condition thermal-performance information. | Moisture can increase effective thermal conductivity, reduce bond strength, promote corrosion, and accelerate deterioration of facing materials. |
| Fire Performance | 15% | Select the required classification according to the project code. European projects may specify EN 13501-1 classifications; North American projects may use ASTM E84 or other system-specific fire tests. | Verify reports for the exact core, facing, adhesive, thickness, joint configuration, and production site. Do not rely only on a generic raw-material certificate. | Fire behavior is a system property. A panel’s classification can change with facers, joints, thickness, coatings, and installation details. |
| Compressive Strength | 10% | Common nominal ranges vary by core and density: EPS approximately 70–250 kPa, XPS approximately 150–700 kPa, and rigid PUR/PIR approximately 100–250 kPa. | Compare compressive-strength data at the required temperature and deformation level. Ask for density tolerance, test direction, and results from production batches. | Adequate strength helps resist handling damage, local loads, wind effects, and deformation around fasteners and supports. |
| Panel Bond Strength and Delamination Resistance | 10% | Require a documented minimum bond or tensile-adhesion value suitable for the selected panel system. The acceptance limit must match the applicable standard and design load. | Review peel, tensile-adhesion, shear, and cyclic-temperature test results. Inspect adhesive coverage, curing conditions, and failure mode in samples. | Strong, uniform bonding reduces the risk of face-sheet separation, loss of stiffness, and water ingress during service. |
| Facing Material and Corrosion Protection | 8% | Confirm steel grade, coating type, coating mass or thickness, paint system, and compatibility with the intended indoor or outdoor environment. | Request coating certificates, salt-spray or corrosion-test data where relevant, thickness measurements, and details for cut edges, fasteners, and protective films. | Corrosion of the facing or fasteners can compromise weather resistance, appearance, structural behavior, and panel service life. |
| Dimensional Accuracy and Joint Quality | 7% | Require controlled tolerances for thickness, length, width, squareness, flatness, camber, and joint fit. Tolerances should be stated in the supplier’s quality plan. | Check inspection records, calibrated measurement tools, sample panels, joint interlock, tongue-and-groove accuracy, and tolerance compliance on several batches. | Accurate dimensions reduce thermal bridging, air leakage, water penetration, installation waste, and visible alignment defects. |
| Quality Management and Batch Traceability | 5% | A qualified supplier should maintain documented incoming-material checks, process controls, final inspection, nonconformance procedures, and batch traceability. | Review quality-system certificates, internal inspection forms, calibration records, corrective-action reports, and batch identification on packaging and delivery documents. | Consistent process control is more reliable than a single favorable sample and helps identify the cause of future defects. |
| Testing Transparency and Standards Compliance | 3% | Test reports should identify the product construction, thickness, density, production date, laboratory, standard, test conditions, and result validity. | Confirm that reports are issued by a competent or accredited laboratory where required and that the tested configuration matches the quotation and purchase order. | Transparent documentation makes technical comparison possible and reduces the risk of substituting a different core, facer, or adhesive after approval. |
