NASCLA Accredited Commercial General ContractorFinishesMedium
A contractor is installing pre-finished architectural wood paneling in a high-traffic commercial lobby. To ensure the durability and longevity of the finish against scratches, abrasions, and chemical spills, which type of factory-applied finish is generally preferred?
- APolyurethane
- BConversion varnish
- CShellac
- DNitrocellulose lacquer
Show answer & explanationAnswer & explanation
Correct answer: A. Polyurethane
Polyurethane finishes, especially catalyzed versions, offer superior hardness, abrasion resistance, and chemical resistance compared to lacquers, varnishes, or shellac, making them ideal for high-traffic commercial applications.
Why the other options are wrong
- B. Conversion varnish offers good durability but polyurethane often surpasses it in extreme environments.
- C. Shellac is a brittle, low-durability finish primarily used for sealing or as a traditional finish.
- D. Nitrocellulose lacquer is fast-drying but not as durable against heavy wear and chemicals.
Polyurethane Finish
A highly durable and protective clear coating for wood, available in oil-based, water-based, and catalyzed (two-part) formulations.
- Offers excellent resistance to abrasion, scratches, and impact.
- Good chemical and moisture resistance.
- Catalyzed polyurethanes provide the highest level of durability for commercial use.
Memory trick: For tough wood, POLYURETHANE is the ultimate protective shield.