Revealing the Importance of Thickenss Swell & Your Laminate Floor’s Water Resistance

Laminate flooring is praised for its durability, affordability, and ability to convincingly mimic hardwood. However, historically, its Achilles’ heel has been water damage. Since traditional laminate uses a core made of compressed wood fibers (HDF), excessive moisture causes this core to swell, ruining the plank’s structure and appearance.

In response to consumer demand and the challenges of humid climates when considering laminate flooring’s water resistance, manufacturers have focused intensely on Thickness Swell resistance.

This metric is a crucial measure of a laminate’s ability to resist the increase in thickness after being exposed to water, and it is the single most important factor for choosing laminate in moisture-prone areas like Florida kitchens, bathrooms, and entryways.

What is Thickness Swell and Why is it Important?

Thickness swell is a laboratory test that measures the percentage of volume increase a laminate sample undergoes after being immersed in water (typically for 24 hours).

1. The Process: A sample of the laminate core is precisely measured, submerged in water for a set period, and then measured again.
2. The Measurement: The difference is expressed as a percentage. For example, a thickness swell of 8% means the plank’s core expanded by 8% of its original thickness.
3. The Impact: When a plank swells, it pushes against the adjacent planks, causing peaking (where the planks lift at the joints), gapping, and ultimately, visible damage to the surface layer, which breaks the illusion of real wood.

The lower the thickness swell percentage, the better the laminate’s resistance to water damage.

The Evolution of Water-Resistant Laminate

Traditional laminate flooring often had a thickness swell of 18% or more—meaning a major spill could quickly cause catastrophic damage.

Modern, water-resistant laminates have drastically reduced this number through two key engineering improvements:

Hydrophobic Core Composition

Manufacturers now treat the High-Density Fiberboard (HDF) core with water-repellent resins and waxes during production. This process minimizes the absorption rate of the wood fibers themselves.

• Result: The core is no longer an immediate sponge, buying you critical time to clean up spills before damage occurs.

Advanced Locking Systems and Sealed Edges

A laminate plank is only as water-resistant as its weakest point: the seams. Modern systems feature highly engineered locking mechanisms that effectively seal the joint when clicked together.

• Bevel Sealing: The beveled edges of the planks are now often coated with a paraffin or wax sealant during manufacturing. When the planks are locked, this wax creates a tight, hydrophobic barrier that prevents water from seeping down into the core.

How to Shop for High-Performance Laminate

When evaluating laminate flooring, focus on these specifications to ensure high thickness swell resistance:

1. Seek the Certification: Look for products explicitly certified as “Water-Resistant” or “Waterproof.” These products usually guarantee low-percentage thickness swell (often 8% or less) when exposed to standing water for up to 24 hours.
2. Check the Warranty: Laminates with excellent thickness swell resistance will clearly state a waterproof warranty that covers topical moisture damage for a specified period (e.g., 24, 48, or even 72 hours). This warranty is the manufacturer’s confidence in their core and sealing technology.
3. Inspect the Edges: In the showroom, look closely at the edges of the plank samples. You should be able to see the subtle waxy or hydrophobic coating applied around the perimeter and within the tongue and groove locking mechanism.

The Role of Installation

Even the most water-resistant laminate requires a perfect installation. If the planks are not properly locked tightly together, or if the necessary expansion gaps around the perimeter are not maintained, water can still find its way into the subfloor, and thermal expansion can damage the seams.

For South Florida’s humidity, professional installation is crucial to ensure the water-resistant features function as intended.

By prioritizing a laminate with proven, low thickness swell properties, you gain the peace of mind to install beautiful, affordable flooring in high-risk areas without the fear of immediate water damage.

For High-Quality Laminate Flooring & Professional Installation Services, Contact Dolphin Carpet & Tile

Call or visit one of our flooring stores throughout Florida including; Coral Springs, FL Davie, FL Deerfield Beach, FL Doral, FL Fort Lauderdale, FL North Miami, Florida Pembroke Pines, FL, Pinecrest-Palmetto Bay, and West Kendall, FL.

For over 51 years in business, Dolphin Carpet & Tile has been synonymous with quality floor covering in South Florida.

Our dedication to customer satisfaction has helped us grow into a market leader. We want all of our customers, past and present, to know that we appreciate their business.