Can Hardwood Floors Be Installed Over Concrete?

Installing hardwood floors can dramatically enhance the aesthetic and value of your home, bringing warmth, durability, and timeless appeal. However, if you have a concrete subfloor, you may wonder if it’s possible to install hardwood floors directly over it. The good news is that hardwood floors can be installed over concrete, but the process requires careful planning and specific considerations to ensure a successful and lasting installation.

In this post, we’ll dive into whether hardwood floors can be installed over concrete, the best methods for doing so, and the considerations you need to keep in mind, especially in an area like Brooklyn, where urban homes often have concrete subfloors.

Can Hardwood Floors Be Installed Over Concrete?

Yes, hardwood floors can be installed over concrete, but there are several things you need to consider before beginning the installation process. Concrete is a sturdy and durable material, but it can be problematic for hardwood flooring if it’s not properly prepared. Unlike wooden subfloors, concrete can be more prone to moisture and temperature fluctuations, which can affect the integrity of your hardwood flooring over time.

To successfully install hardwood floors over concrete, you'll need to address the potential issues with moisture, leveling, and proper installation techniques.

Considerations Before Installing Hardwood Floors Over Concrete

1. Moisture Concerns

• Concrete’s Absorption of Moisture: Concrete is porous, meaning it can absorb moisture from the ground beneath it. If there’s excessive moisture in the concrete, it can seep into your hardwood flooring, leading to warping, buckling, or mold growth. This is especially important in areas like basements, which often have higher humidity levels.
  
  

• Testing for Moisture: Before installing hardwood floors over concrete, you should test for moisture content. This can be done with a moisture meter or by using a plastic sheet test, which helps you determine whether moisture is present beneath the surface. The moisture level of the concrete should be below a certain threshold to ensure the safety of your hardwood flooring. The acceptable moisture level is generally less than 4% for solid hardwood and around 6% for engineered hardwood.
  
  

• Moisture Barriers: If moisture is present or there’s a risk of moisture, you’ll need to install a moisture barrier. This is typically a plastic vapor barrier or a special underlayment designed to prevent moisture from reaching the hardwood floors. The barrier is usually laid over the concrete before the hardwood is installed.
  
  

2. Leveling the Concrete

• Uneven Concrete Floors: Concrete subfloors may have imperfections such as cracks, divots, or uneven spots. These irregularities can affect the stability and appearance of your hardwood floors. If the concrete is uneven, it will be necessary to level the surface before installation.
  
  

• Self-Leveling Compound: If your concrete floor is significantly uneven, a self-leveling compound can be applied to smooth it out. This compound is poured over the concrete and spreads out to create a flat, smooth surface for hardwood installation.
  
  

• Concrete Slab Condition: Cracks in the concrete should also be filled and sealed before installation. You can use a concrete patching compound to fix small cracks. If there are large cracks, it may be necessary to have the concrete slab repaired by a professional before proceeding with the hardwood installation.
  
  

3. Type of Hardwood Flooring

• Solid Hardwood vs. Engineered Hardwood: While solid hardwood can be installed over concrete, engineered hardwood is often a better option due to its greater stability in fluctuating temperatures and humidity levels. Solid hardwood may expand and contract with changes in the environment, which can cause problems when installed over concrete.
  
  

• Engineered Hardwood: Engineered hardwood is made of multiple layers, including a hardwood veneer on top of several layers of plywood or HDF (high-density fiberboard). This construction makes engineered hardwood more stable and less prone to expansion and contraction, making it an ideal choice for installation over concrete.
  
  

4. Installation Methods

• Floating Floor Installation: One of the most common methods of installing hardwood floors over concrete is the floating floor method. With floating floors, the hardwood is not nailed or glued to the concrete subfloor. Instead, the individual planks are connected to each other, and the entire floor “floats” over the subfloor.
  
  

• Glue-Down Method: For engineered hardwood, the glue-down method can be used. In this method, the hardwood planks are glued directly to the concrete subfloor. The adhesive used must be specifically designed for use with concrete and should be moisture-resistant. This method works best when the concrete is relatively level and dry.
  
  

• Nail-Down Method: The nail-down method, which is typically used for solid hardwood flooring, is not recommended for concrete subfloors. Since concrete is too hard to nail into, this method would require additional materials like a plywood underlayment, which can add to the complexity and cost of the project.
  
  

5. Underlayment

• Importance of Underlayment: Underlayment is often used when installing hardwood over concrete. It serves multiple purposes, including moisture protection, sound reduction, and cushioning for the floor. For engineered hardwood, the underlayment can be installed between the concrete and the hardwood planks. This is especially important when using the floating floor method, as it helps to minimize sound and provide a more comfortable walking surface.
  
  

• Foam or Cork Underlayment: Foam and cork are two of the most common types of underlayment used when installing hardwood floors over concrete. Foam is often used for its moisture-resistant qualities, while cork can provide better sound insulation.
  
  

Steps for Installing Hardwood Floors Over Concrete

If you decide to install hardwood floors over concrete, here is a general overview of the steps you should follow:

1. Prepare the Concrete Subfloor:
   
   

• Clean the concrete thoroughly, removing any dust, dirt, or debris. If necessary, patch any cracks or holes in the concrete.

• Test for moisture content and address any moisture issues by installing a vapor barrier or moisture-resistant underlayment.

2. Level the Concrete:
   
   

• Use a self-leveling compound if the concrete is uneven. Allow the compound to dry completely before proceeding.

3. Install Underlayment:
   
   

• Lay down a moisture barrier or underlayment. Ensure that the underlayment covers the entire floor and overlaps at the seams to prevent moisture from seeping through.

4. Install Hardwood Flooring:
   
   

• Depending on the method you're using, either glue, nail, or float the hardwood planks over the concrete.

• Start at one edge of the room and work your way across, ensuring that each plank is properly aligned and securely connected.

5. Finishing Touches:
   
   

• Install baseboards or moldings around the edges of the floor to cover any gaps. This will give the floor a polished, finished look.

Cost of Installing Hardwood Floors Over Concrete in Brooklyn

The cost of installing hardwood floors over concrete in Brooklyn can vary depending on several factors, including the size of the area, the type of hardwood flooring, and the complexity of the installation. On average, you can expect to pay between $6 to $15 per square foot for hardwood floor installation over concrete. This price includes both labor and materials, but additional costs for moisture barriers, underlayment, and repairs to the concrete subfloor may increase the overall price.

Conclusion

Yes, you can install hardwood floors over concrete, but it's essential to take the necessary steps to ensure that the installation is done correctly. Moisture, leveling, and choosing the right type of hardwood flooring are critical factors that can impact the success and longevity of your floors. While engineered hardwood is often the best choice for concrete subfloors, solid hardwood can be used if the proper precautions are taken. Whether you're in Brooklyn or beyond, following these guidelines will help you achieve a beautiful, long-lasting hardwood floor installation over concrete.