The promise of PU moldings — never crack, warp, or rot — is one of the strongest selling points for the material. The promise is based on the physical properties of the PU, and it's a real advantage over wood, MDF, and plaster.
The "never crack" claim is based on the PU's flexibility. The closed-cell PU has enough flexibility to absorb small movements in the building without cracking. Wood and MDF are rigid, and they crack when the building moves. The PU's flexibility is enough to handle normal seasonal movement, normal settling, and normal impact without damage.
The "never warp" claim is based on the PU's dimensional stability. The PU doesn't absorb water, so it doesn't swell or warp with changes in humidity. Wood and MDF absorb water and warp with humidity changes, and the warping is visible at the joints and the surfaces. The PU's stability is enough to handle any humidity level, from a desert to a tropical climate.
The "never rot" claim is based on the PU's biological inertness. The PU is not a cellulose material, so it doesn't provide a food source for rot fungi, termites, or other wood-boring organisms. Wood and MDF are cellulose materials, and they rot in moist environments. The PU's inertness is permanent — the material doesn't degrade biologically.
For sourcing, the right conversation with the factory is about the specific properties of the PU. The factory should be able to provide test data on the material's flexibility, dimensional stability, and biological resistance. A factory that has the test data in order is a factory that stands behind its products.
A practical note on the limitations. The "never crack, warp, or rot" claim is true for normal applications, but it's not absolute. A PU molding can be damaged by severe impact (a hammer blow, a heavy object dropped on it), by extreme heat (a fire), or by certain chemicals (strong solvents, acids). The PU is more durable than wood or MDF in normal applications, but it's not indestructible.
A practical note on the warranty. Many PU manufacturers offer a warranty against cracking, warping, and rotting, with the warranty valid for 10 to 25 years. The warranty is worth checking before the order is placed, and the documentation should be kept on file for the project records.
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Frequently Asked Questions
Q: What is your factory MOQ?
A: MOQ depends on the product line: stock cornice and skirting profiles start at 200 linear meters per shipment, wall panels at 50 square meters, and custom OEM/ODM profiles at 500 linear meters or 1,000 pieces. Sample orders are accepted for most catalog items, with sample fees credited toward the first bulk order.
Q: What are your standard lead times?
A: Stock catalog items ship within 7–15 days of order confirmation. Custom tooling for OEM profiles takes 25–35 days for sample approval plus 20–30 days for bulk production. Air freight from Guangzhou / Shenzhen takes 5–10 days to most major ports; sea freight takes 18–32 days depending on destination.
Q: Do you offer OEM and ODM services?
A: Yes. Our factory offers full OEM (your brand, our tooling) and ODM (your 3D model or sample, our design team reverse-engineers and produces custom tooling) services. We can sign NDAs, work from hand sketches, photographs, or CAD files, and ship samples for approval before bulk production.
Q: What are your payment terms?
A: Standard terms are 30% T/T deposit on order confirmation and 70% balance against a copy of the B/L. For new buyers we also accept 100% L/C at sight. Long-term partners can apply for open-account terms after three successful orders.