Installing Laminate Flooring in a Basement: What You Need to Know
Why Basements Are Different:
Basements are below grade, so in this case "Grade" means where the ground you walk on. Basements are "Below" grade or under ground and surrounded by soil. This creates two big challenges for flooring:
- Moisture: Concrete is porous and can release water vapor. Heavy rains or saturated soil can also cause small leaks or seepage.
- Temperature & Humidity: Concrete subfloors are naturally cold and poor insulators. The humidity changes during the year, and the limited to no airflow in a basement, is a difficult environment for laminate or any type of flooring.
Without proper preparation and understanding of how this will affect your floor, can easily lead to mold and mildew damage, buckling of the floor and costly repairs.
Can You Install Laminate in a Basement?
Absolutely, but you need to address the comfort and protection levels you want to achieve before you start. When Installing a laminate floor in the basement, or any flooring for that matter, not protecting your home from moisture is a huge mistake.
Basement-Specific Challenges
Laminate floors in basements are more vulnerable when:
- No moisture barrier or subfloor protection is used
- The concrete floor isn’t tested for moisture before installation
- There’s no plan for humidity control year-round
- Installed directly on cold concrete
Steps to a Successful Basement Laminate Installation
1. Test for Moisture Before You Begin
Use a moisture meter or calcium chloride to measure vapor levels.
You can also use a 24" x 24" piece of poly (or a cut garbage bag) and tape it tight to the floor. wait 24 - 48 hours. If there is any condensation or water on the plastic or discoloration of the concrete, there is a definite moisture issue. If there is a positive result in any of these situations, then strong vapor barrier is a must.
Read: Do I Need a Moisture Barrier for Laminate on Concrete?
2. Using the Right Underlay or Subfloor System
A 6 mil plastic sheet is the absolute minimum for vapor protection, but for basements, a dimpled subfloor membrane is far more effective. They create an air gap between the concrete and laminate that lets the floor breathe and allows moisture to evaporate instead of getting trapped against the underlay or flooring.
Read: What’s the Best Underlay for Laminate Over Concrete?
3. Control Basement Humidity
Ideally you want to keep relative humidity between 30%–50% using a dehumidifier. This helps protect your floors from excess moisture, and your entire basement environment.
4. Leave the Correct Expansion Gap
Wood expands and contracts as the temperature changes. For example, It's why doors may stick a little more in the summer. A laminate floor needs room to expand and contract with temperature and humidity changes. Always follow the manufacturers installation instructions for spacing around walls and edges. They will have the proper measurements for their product.
5. Proper Floor Maintenance
- Keep your floor clean. This will help avoid grit that can scratch the surface.
- Clean up spills immediately. This help keep liquid from seeping into the wood.
- Especially in basements, keep humidity in check to protect your floor and make it last longer.
- Inspect for leaks seasonally, especially after heavy rainfall or snowmelt. Look for damp patches, water stains, or musty odors along walls and floor edges. If you have an unfinished utility area or storage space, lift a small section of flooring or underlay to check for and hidden moisture.
Comfort and Warmth Considerations
Even if moisture isn’t an issue, concrete basement floors are cold year-round, especially in the winter months.
Using a subfloor with a thermal break (usually a dimple subfloor membrane) takes the edge off the cold concrete and helps retain heat, improve comfort, and can even reduce heating costs. This is especially important in basements that are used as living space, home office, or a playroom.
In Summary
Laminate flooring can be an excellent basement choice. It's stylish and far cleaner and easier to maintain than carpet. But as with all flooring, you have to protect it from moisture.
In all basements and slab on grade floors, cold concrete, humidity fluctuations, and the potential for hidden moisture. Controlling these factors from the ground up protects you flooring. So, test your concrete, choose the right underlay or subfloor, and manage humidity year-round.
All-In-One Subfloor was designed with basements in mind. Its built-in moisture barrier with a dual air-gap that helps airflow above and below the rugged HDPE core. All-In-One is designed to give yo peace of mind that your will floor stay dry, warm, and protected for years to come.