The core trade‑off is panel thickness versus thermal performance and shipping cost; a 50 mm core meets most cold‑store U‑values but adds 2.3 kg/m² over a 30 mm option, so buyers must balance energy savings against container loading limits.

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How It Is Built and What That Changes

Panels start as a continuous double‑belt press where liquid polyurethane is injected between two pre‑coated metal skins. The foam expands in‑situ, bonding to the skins without adhesives, which eliminates a common delamination path. Skin thickness typically ranges from 0.4 mm to 0.7 mm; thicker skins improve impact resistance but increase weight and cost per square metre.

Density of the cured core is set by the formulation and press speed; a target of 40 kg/m³ gives a thermal conductivity around 0.022 W/m·K, while 45 kg/m³ pushes it to 0.020 W/m·K at the expense of a 5 % weight penalty. The line can switch densities in 30 minutes, so a single run can produce mixed‑thickness orders without a full changeover.

Buying Mistakes That Lead to Returns

The most frequent claim is water ingress at the panel edge because the buyer specified a standard sealant groove but the installer used a generic butyl tape that does not accommodate the 1.5 mm thermal expansion of the steel skin.

Ordering a single core density for both roof and wall zones creates over‑specification on walls and under‑performance on roofs.
Skipping the factory‑applied edge sealant to save $0.12/m² leads to warranty claims that cost 10× that amount.

A second source audit should verify that the supplier runs a daily adhesion peel test (minimum 0.8 MPa) and a weekly thermal conductivity check on a representative sample.

Customisation Options and Their Limits

Colour, profile, and facing material are the three levers that affect lead time and MOQ. The table below summarises the practical envelope.

Option	Range / Choices	Impact on MOQ / Lead Time
Core thickness	30 mm, 40 mm, 50 mm, 60 mm, 80 mm	Standard 30‑50 mm: 500 m² MOQ, 15 days; 60‑80 mm: 1 000 m² MOQ, 25 days
Skin material	Pre‑painted galvanized steel (0.4‑0.7 mm), Aluminum (0.5‑0.8 mm)	Steel: 300 m² MOQ, 10 days; Aluminum: 800 m² MOQ, 20 days
Coating system	Polyester 25 µm, PVDF 25 µm, SMP 35 µm	Polyester stocked; PVDF adds 5 days, SMP adds 7 days
Profile	Trapezoidal, sinusoidal, flat‑lock, standing seam	Standard trapezoidal 200 m² MOQ; custom profile tooling 4 weeks, 2 000 m² MOQ

PVDF offers the best colour retention in high‑UV zones but adds $1.8/m²; if the project is inland and budget‑driven, polyester is usually sufficient.

Quality Control and Batch Consistency

Every shift runs a density check on a 300 mm × 300 mm coupon; the acceptance window is ±2 kg/m³. Adhesion is verified by a 90° peel test on three random panels per 1 000 m²; failure triggers a full line stop and root‑cause investigation. Dimensional tolerance on length is ±3 mm, on width ±2 mm, and on thickness ±1 mm. Thermal conductivity is sampled weekly using a guarded hot‑plate per ASTM C518; results are logged to the batch traceability sheet that ships with each container.

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A buyer who requires a certificate of conformity for each lot should request the test data package at order confirmation; the factory can embed a QR code on the panel label linking to the PDF.

Capacity, Tooling and Scheduling

The plant operates two parallel double‑belt lines, each capable of 12 000 m² per 24‑hour shift at 40 mm core. Changeover between core thicknesses takes 30 minutes; skin material changeover takes 2 hours because the coil feeder must be swapped. Peak season (Q3) runs at 90 % utilisation, so a 5 000 m² order placed in June typically ships in early August.

Core Thickness (mm)	Panel Weight (kg/m²)	Typical U‑value (W/m²·K)	Max Span (m) – Steel 0.5 mm
30	9.8	0.73	3.0
40	11.2	0.55	3.6
50	12.6	0.44	4.2
60	14.1	0.37	4.8
80	17.0	0.28	5.5

If the project calls for a 5 m clear span, the 50 mm core with 0.5 mm steel skin is the lightest viable option; anything thinner will require additional purlins and raise total installed cost.