Mil vs mm: What Flooring Thickness Really Means

Introduction

Choosing new flooring is exciting, but it can quickly become confusing when product labels start listing numbers, thickness measurements, and terms that don’t seem to match. One of the most common areas of confusion for homeowners is the difference between mil and millimeters (mm), especially when comparing vinyl, SPC, or rigid-core plank flooring. Some products are labeled in mm, others in mil, and many people understandably assume they mean the same thing.

In this beginner-friendly guide, we’ll explain what each measurement really refers to, how thickness relates (and doesn’t relate) to quality, and when thicker flooring truly matters, all in plain English, with no manufacturer jargon or pressure to choose one product over another.

The goal is simple: to help you make a clear, confident flooring decision without overwhelm.

Mil vs mm: Why Flooring Uses Two Different Measurements

Let’s start with the most important clarification.

Mil and millimeters are not the same thing.
They measure two completely different parts of a flooring plank.

What “mm” Measures

Millimeters (mm) measure the total thickness of the plank, including:

• Wear layer

• Printed design layer

• Core

• Backing or underlayment (if attached)

So when a floor is labeled:

• 4 mm

• 6.5 mm

• 8 mm

That number describes the overall plank thickness from top to bottom.

What “mil” Measures

Mil (not to be confused with millimeter) measures the wear layer thickness only.

The wear layer is the transparent protective coating that:

• Guards against scratches

• Reduces visible wear

• Protects the printed pattern layer

• Extends the usable lifespan

Common flooring wear layer ratings include:

• 6 mil

• 8 mil

• 12 mil

• 20 mil

• 28 mil (and higher in commercial products)

So while mm describes plank thickness,
mil describes durability of the top protective layer.

They measure different things, which is why comparing them directly can be misleading.

Why Thicker Planks Aren’t Always “Better Quality”

A common assumption is:

“Thicker flooring must be higher quality.”

But in reality, two floors can have:

• The same plank thickness with very different durability

Or:

• Different thickness with nearly identical performance

Because overall thickness has less impact on wear than most people expect.

What mm Thickness Typically Affects

Plank thickness usually relates more to:

• Stability

• Sound absorption

• Comfort underfoot

• Height transitions between rooms

• How forgiving flooring is over small subfloor imperfections

Thicker planks often:

• Feel slightly more solid

• Can reduce hollow or clicking sounds

• Provide a more cushioned step when paired with good underlayment

But thickness alone does not guarantee:

• Longer lifespan

• Better scratch resistance

• Higher surface durability

Those qualities are driven primarily by the wear layer (mil) and core construction.

What Matters More Than Overall Thickness: The Wear Layer

If durability is your priority, the wear layer matters more than the mm thickness.

Here’s why.

The wear layer is the part that:

• Takes daily foot traffic

• Comes into contact with pets and furniture

• Resists scratches and abrasions

• Determines how long the floor looks good

Two planks can both be 6 mm thick, but:

• One has a 6 mil wear layer

• One has a 20 mil wear layer

They will not wear the same way over time.

The plank with the thicker wear layer typically holds up longer, even if the total mm thickness is the same.

Common Real-World Scenarios Homeowners Ask About

“We have kids and pets. Which measurement should I care most about?”

Prioritize:

• 12 mil or higher wear layer

• Stable rigid-core construction

• Proper subfloor preparation

Plank thickness (mm) is helpful for comfort, but the wear layer drives durability.

“We want something comfortable but not too thick for door clearance.”

Then mm thickness matters more for:

• Height transitions at doorways

• Appliance and fixture clearance

• Visual profile

The best balance is often:

• Moderate plank thickness

• Strong wear layer

Instead of choosing by thickness alone.

“We saw a very thick floor at a store. Does that mean it’s premium?”

Not always.

Some ultra-thick planks:

• Market “heft” as quality

• Add thickness through backing layers

But do not necessarily improve real durability.

Meanwhile, a slightly thinner plank with a stronger wear layer may perform better long-term.

When Thicker Flooring Can Be Helpful

There are situations where plank thickness makes a meaningful difference.

Thicker flooring may be beneficial when:

• You want better sound absorption in multi-level homes

• You prefer a more solid underfoot feel

• Your existing subfloor has minor imperfections

• You are replacing old laminate or tile and want similar height

Just remember:

Thickness improves feel, not always lifespan.
And it should never be the only deciding factor.

Quick Guide: How to Use Mil vs mm When Comparing Flooring

Here is an easy beginner framework.

Use mm (millimeters) to evaluate:

• Comfort underfoot

• Room transitions

• Acoustic feel

• Floor height profile

Use mil (wear layer) to evaluate:

• Daily durability

• Scratch resistance

• Expected lifespan

• Suitability for kids, pets, or busy homes

Both numbers matter.
They just answer different questions.

Beginner Takeaway: Thickness Should Support Your Lifestyle, Not Impress on Paper

Flooring is not about winning a spec sheet comparison.

It’s about:

• How your home is used

• How you want it to feel

• How long you expect it to last

• Which trade-offs matter most to you

Thickness (mm) helps with comfort and stability.
Wear layer (mil) helps with durability and longevity.

When you understand the difference,
flooring choices become clearer and far less overwhelming.

Conclusion

Understanding the difference between mil and millimeters helps clarify what flooring thickness really means in everyday use. Millimeters describe the total plank thickness and how a floor feels underfoot, while mil refers to the wear layer that protects the surface and influences how well the floor stands up to daily life. When you evaluate both measurements together instead of comparing them with each other, it becomes much easier to choose flooring that fits your home, your lifestyle, and your expectations.

Now that you have a clear picture of how thickness is measured and why it does not tell the whole story, the next step is to look at the part of the floor that does most of the heavy lifting: the wear layer. In the next guide, we will explain what a wear layer is, how it affects durability, and why it often matters more than overall plank thickness. If you would like to see different flooring constructions side by side and compare them in person, Visit our Showroom.