Yes, underlayment is generally required for laminate flooring installations, unless the laminate planks you purchase come with a pre-attached underlayment pad (and even then, some situations might call for additional underlayment). Underlayment is a thin padding (often foam or felt) that is laid between the subfloor and the laminate planks. It serves several purposes:

• Cushioning and Comfort: It provides a slight give underfoot, making the floor more comfortable to walk on than having the laminate directly on a hard subfloor.

• Sound Reduction: Underlayment helps absorb sound, reducing the hollow tap sound when walking on laminate. This is especially important in multi-level homes or apartments – it cuts down on noise transmission to rooms below.

• Minor Leveling: Underlayment can even out very small imperfections in the subfloor and provide consistent support for the laminate. (Note: it will not correct major subfloor unevenness, which should be fixed prior to installation. But it can take up tiny gaps or textures.)

• Moisture Barrier: Some underlayments have an integrated vapor barrier or you can lay a separate plastic sheet as a moisture barrier. This is crucial when installing laminate over concrete or any subfloor that could emit moisture. The barrier prevents moisture from seeping up into the laminate. (Many underlayments for laminate will have a plastic film or are made of closed-cell foam that resists moisture.)

When is underlayment needed?

• Always for floating laminate: If your laminate is the floating type (which most are), you will place it over an underlay. It’s part of the standard installation procedure.

• Exceptions: If the laminate planks have pre-attached underlayment (for example, some products have a foam backing already stuck to each plank), you typically do not add another underlayment on top of that. The attached pad acts as the underlayment. You might still need a separate vapor barrier sheet over concrete, unless the attached pad has a vapor barrier feature. Check the manufacturer’s instructions.

• Plywood subfloor vs Concrete: Over plywood or wood subfloors, underlayment is primarily for sound and cushion. Over concrete, you must also have a moisture barrier (either integrated or separate plastic sheeting) to protect from slab moisture.

Types of underlayment: Common laminate underlayments include foam roll underlay (like a thin polyethylene foam), felt underlayment, or cork underlayment. Some have added features like a foil moisture barrier or extra thickness for sound. Choose one that is recommended for use with laminate. Using a high-density underlay can also improve the solidity of the floor.

Note: Underlayment is relatively inexpensive but provides a big benefit in performance of your laminate floor. Skipping underlay (or forgetting the moisture barrier on concrete) can lead to problems like loud floors or moisture damage. So yes, laminate floors do need underlayment padding, and in fact installing laminate directly on a subfloor without it would likely void the warranty and result in a less satisfying floor.