Underlayment Requirements for Vinyl Plank Flooring on Concrete

[Gardenboy]

Hi everyone,
Is underlayment necessary when installing vinyl plank flooring over a concrete subfloor? What’s typically recommended for moisture protection, comfort, and long-term durability?

Thanks in advance!

[Downaski]

Hey there,

Underlayment isn’t always required, but it’s usually a good idea when you're laying vinyl plank flooring over concrete. Concrete tends to hold moisture, so having an underlayment with a moisture barrier can help protect your flooring from damage over time. It also adds a bit of cushioning, which makes the floor feel more comfortable to walk on, and it can help with noise too. Some vinyl planks already come with underlayment attached, so in that case, you might not need anything extra. But if they don’t, adding a proper underlayment can really help with comfort and durability in the long run.

[Gardenboy]

Does the thickness of the underlayment make a noticeable difference when installing vinyl plank flooring?

[Downaski]

With vinyl plank flooring, underlayment thickness does not need to be very high. In fact, using underlayment that is too thick can sometimes cause issues with the locking mechanism of the planks. Most vinyl flooring only needs a thin underlayment that provides a moisture barrier and a bit of cushioning. Something around 1 to 2 millimeters is usually enough. If the planks already have padding attached, extra underlayment is typically not needed.

[Gardenboy]

That makes sense. Is there a specific type of underlayment you'd recommend for concrete in a basement?

[Downaski]

For basements, it's best to use an underlayment that includes a built-in moisture or vapor barrier. Concrete floors can hold a lot of moisture, so this extra layer helps protect the vinyl planks from damage over time. Look for something made specifically for use over concrete and compatible with vinyl flooring. If your planks already have padding attached, you might not need an additional layer, but it's always good to double-check the manufacturer's guidelines.

[Gardenboy]

Really appreciate all the advice, thank you!