Which material is not permissible as underlayment for hardwood floors?

Which material is not permissible as underlayment for hardwood floors?

• A. OSB Plywood
• B. CDX Plywood
• C. Particle Board
• D. Plywood CC

Answer: (C)

Underlayment for hardwood floors must provide a stable, smooth surface that won’t swell, delaminate, or loosen fasteners, and it should resist moisture enough to keep the floor level and quiet over time. Particle board fails these tests because it absorbs moisture readily, swells and deteriorates, and doesn’t hold nails or screws well. That makes it unsuitable as an underlayment for hardwood. In contrast, materials like OSB or plywood (including grades such as CDX or CC) offer better dimensional stability, a solid nailing or bonding surface, and greater resistance to moisture-related distortion when used with the proper installation details.

Underlayment for hardwood floors must provide a stable, smooth surface that won’t swell, delaminate, or loosen fasteners, and it should resist moisture enough to keep the floor level and quiet over time. Particle board fails these tests because it absorbs moisture readily, swells and deteriorates, and doesn’t hold nails or screws well. That makes it unsuitable as an underlayment for hardwood. In contrast, materials like OSB or plywood (including grades such as CDX or CC) offer better dimensional stability, a solid nailing or bonding surface, and greater resistance to moisture-related distortion when used with the proper installation details.