Underlayment is the often-unseen foundation of a laminate installation, and its importance cannot be overstated. Since laminate is a floating floor, the underlayment is the thin layer between the subfloor and the planks.
It performs three critical jobs: cushioning, sound dampening, and moisture protection, all of which are essential for the floor's long-term performance and the comfort of the home's occupants.
Moisture Barriers vs. Sound Dampening
Underlayments come in various types, each prioritizing a function:
Moisture Barrier: This is a thin plastic film that is critical for installations over concrete or in below-grade (basement) environments. Its primary job is to stop water vapor from rising out of the concrete and penetrating the HDF core of the laminate plank. A separate vapor barrier is necessary unless the underlayment is integrated into a single product.
Acoustic/Sound Dampening: Made of dense foam, felt, or rubber, this type is designed to absorb the impact of footsteps. It minimizes the "hollow" or "clicky" sound (Impact Insulation Class - IIC) associated with floating floors, greatly improving the acoustic quality of the space both in the room and the room below.
Required Underlayment for Click-Lock Systems
Nearly all floating laminate floors require an underlayment to function correctly and to validate the warranty. The underlayment does not just manage noise; it provides a minor cushion that helps the click-lock joints engage properly and stay intact.
Some newer, premium laminates feature an attached pad, a thin layer of foam or cork permanently affixed to the bottom of the plank. While convenient, the quality of this attached pad may not be as high as a premium separate underlayment, and in moisture-prone areas, a separate moisture barrier may still be needed.
Addressing Subfloor Imperfections
While a subfloor must be flat before installation (level within 3/16 inch over 10 feet), the underlayment helps mitigate very minor, localized imperfections. It provides a degree of cushioning that prevents the plank from flexing and squeaking over slight height differences.
However, it is not a leveler. Using a very thick or spongy underlayment to compensate for a very uneven subfloor is a major mistake. It can lead to too much bounce, causing the click-lock joints to disengage or even break under heavy foot traffic.
Choosing Underlayment Thickness
Underlayment thickness is typically measured in millimeters or mil (a thousandth of an inch). Choosing the right thickness depends on the installation:
Too Thin: Won't provide adequate sound dampening or joint support.
Too Thick or Spongy: Can allow too much vertical movement, stressing the click-lock seams and causing the joints to fail.
Always follow the flooring manufacturer's specific recommendations for underlayment material and thickness to ensure optimal performance and joint integrity.
For More Information, Contact National Flooring Outlet
A properly chosen underlayment is the unsung hero of a successful laminate installation. It transforms a potentially hollow, clicky surface into a quiet, comfortable, and structurally protected floor. By dampening sound and providing essential stability, the underlayment safeguards your investment and maximizes the everyday comfort of your home. Ready to ensure your next flooring project sounds and feels substantial, all while offering superior protection?
Stop by National Flooring Outlet in Monrovia, CA today to explore thousands of in-stock premium laminate options and the right underlayment, ready for same-day pickup. Our experts can help you select a beautiful, high-quality floor that maximizes your home’s value and performance. Give us a call to speak with a flooring expert or visit our warehouse!
