Luan Underlayment: When And How Do You Install Them

Luan Underlayment

Last Updated on July 24, 2023 By Emma W. Thomas

To install Luan underlayment, follow these steps:

  • Use it for resilient floor coverings like vinyl or laminate.
  • Ensure the subfloor is clean and smooth.
  • Lay Luan sheets perpendicular to the subfloor.
  • Secure with adhesive or staples every 6 inches.
  • Leave gaps at edges for expansion.
  • Trim excess for a neat finish.
Luan Underlayment

When To Use Luan Underlayment

Luan underlayment is used in various scenarios when installing resilient floor coverings. Here are the details in points:

  1. Resilient Floor Coverings: Luan underlayment is primarily used for floorings that require a smooth, even surface, such as vinyl or laminate floors.
  2. Subfloor Preparation: If the existing subfloor is uneven, damaged, or unsuitable for direct installation, Luan underlayment can be added to create a stable base.
  3. Imperfection Prevention: Luan helps prevent imperfections from the subfloor, such as bumps, cracks, or gaps, from telegraphing through the finished floor, ensuring a more visually appealing result.
  4. Extra Protection: It offers an extra layer of protection against moisture, providing a barrier between the subfloor and the resilient flooring.
  5. Noise Reduction: Luan underlayment can help reduce impact noise, creating a quieter and more comfortable living environment.
  6. Easy Installation: Luan sheets are lightweight and easy to handle, making the installation process more manageable.
  7. Cost-Effective Option: Compared to other underlayment materials, Luan is generally cost-effective, making it a popular choice for budget-conscious projects.

Remember to always follow the manufacturer’s guidelines and recommendations for specific floor materials and installation methods when using Luan underlayment. Additionally, it’s essential to ensure proper ventilation and address any moisture issues before installation to avoid potential problems in the future.

How To Install Luan Underlayment?

Generally, Luan plywood is installed on top of a subfloor because the sheets aren’t structurally sound and don’t take the place of a subfloor. For proper installation of Luan underlayment, follow these steps;

Step1:  Tools And Materials Needed

To install Luan plywood underlayment in your house, you need a few essential carpenter tools like a circular saw and a staple gun. A utility knife is also handy for cutting Luan to fit around corners. To make accurate cuts in the panels, a measuring tape and a chalk line are very necessary

Luan installation does not need adhesive, but if need be, choose a subfloor adhesive. Then, stock up on ¼ -inch crown staples that are one inch long.

Step 2: Determining The Size And Surface Area

Determine the size and surface area of your subflooring that Luan underlayment needs to cover.  To get the area required to cover the subfloor, use a tape measure to measure the areas. Divide the area by 32 square footage to enable you to calculate the number of Luan plywood sheets you’ll need. Allow the Luan plywood underlayment to adapt to the area in which you’ll install it. This prevents the Luan wood from bubbling when it’s attached to the subfloor.

Step 3: Clean The Subfloor 

Sweep your floor to remove all dirt, debris, and dust. Check and remove any screws or nails sticking out of the subfloor. Afterward, fill in the gaps with fillers or floor patching compounds according to your manufacturer’s instructions. Give time for the compound soil to dry and sand any bumps remaining to achieve a flat patching surface.

Step 4: Measure And Cut The Luan Plywood

Measure and cut the Luan underlayment using a circular saw to cut edges against your walls. Try and fit the Luan plywood to ensure your measurement calculations are correct. 

Step 5: Install Your Luan Plywood Into The Subfloor

One by one lay the Luan underlayment perpendicular to the subfloor. Make sure you leave a ¼-inch space between the cut edges and your walls. Leave not less than a 1/8 inch gap between your sheets of Luan under layers as well.

Next, remove your Luan plywood and spread enough adhesive with a 1/8-inch notched trowel covering the surface area of the first patch of the Luan patch. Keenly install Luan underlayment with a stapler shorter than the backing plus the patch’s total depth.

Later, hammer the staples flush with the surface of your Luan plywood underlayment. Then, remove any piece of wood that might have shattered in the staples.

Step 6: Install The Remaining Luan Underlayment Pieces

Continue and install the remaining pieces of Luan underlayment until they are all finished.

Step 7: Fill In The Gaps

Fill in any gaps against the walls or the holes left by the chipped wood. Plus, the spaces between the plywood seams using a flooring compound and allow the compound to dry out. After that, sand the seams smoothly using an orbit sander for a smooth and flat surface.

At this point, you’re done with your Luan underlayment installation, and it’s ready to install your flooring cover, such as vinyl.

Materials Needed For Luan Underlayment

When preparing for your Luan underlayment project, it’s essential to compile a list of materials needed prior to beginning the project. Here’s a comprehensive guide to all the materials necessary for a successful, smooth installation:

  1. Luan Plywood Sheets: These typically come in 4×8 feet sheets. The amount of sheets needed will depend on the size of the space you plan on installing the underlayment.
  2. Plywood Cutting Saw: You will need a proper tool to cut the Luan sheets to fit the specific dimensions of your project.
  3. Carpenter’s Pencil and Measuring Tape: These tools are crucial for measurements and marking the plywood for precise cuts.
  4. Screws and Nail Gun or Stapler: You will need these to securely attach the Luan underlayment to your subfloor. Make sure to choose screws or nails that are intended for underlayment and will not pop through the finished floor.
  5. Level: It is essential that your underlayment is flat and level for the best results.
  6. Adhesive: Specific types of glue or adhesive may be required to firmly secure the Luan underlayment to the subfloor.
  7. Sand Paper: This is important for sanding down any edges or imperfections in the Luan sheets.
  8. Safety Goggles and Gloves: Personal protective equipment is a must to ensure safety during the project.
Luan Plywood SheetsMain material for the underlayment
Plywood Cutting SawFor cutting the Luan sheets
Carpenter’s Pencil and Measuring TapeFor measurement and precise cuts
Screws and Nail Gun or StaplerFor attaching the underlayment to the subfloor
LevelFor ensuring the underlayment is flat and even
AdhesiveFor securing the underlayment
Sand PaperFor smoothing out imperfections
Safety Goggles and GlovesPersonal protective equipment

Different Ways To Fasten Underlayment To Subfloor

Mostly, flooring underlayment is installed over your subfloor. Usually, some installers lay the underlayment on the floor and begin installing the laminated flooring on top. Meaning there’s no fastening the underlayment to the subfloor.

A few installers like to fasten underlayment to the subfloor during installation to prevent it from moving. To fasten your underlayment to the subfloor, you can use;

  • Staples:  they are a perfect choice to fasten your Luan underlayment. Generally, they have a coating that helps increase the holding power, staple 2 inches over the seams plus edges using a crown compression with 4-6 inches apart in the middle.
  • You Can Glue-Down Underlayment: Please refer to your flooring manufacturer’s installation instructions if your flooring is a glue flooring installation type on a specific glue recommendation. However, subfloor adhesive is the best; you can use the BEST urethane Adhesive or DriTac 5900 Mega Bond.

Is Luan Plywood Underlayment Waterproof?

Luan plywood underlayment is generally designed to be used indoors, meaning that it isn’t waterproof. But, it’s possible to find an exterior kind of Luan that you could use in a shed or any other outdoor building project. Such types are crafted with different adhesives that stand up better to moisture. Make sure you clarify the type of Luan you’re looking at with your lumberyard before making any significant purchases.

Helpful Tips And Techniques When Installing Luan Underlayment

1. Use a chalk line on the backside of the panel as a guide.

2. To prevent splintering on the face of your sheet, cut Luan with the circular saw from the backside.

3. You can cut small areas from the front side of your Luan plywood with a utility knife because they are lightweight and thin.

4. Instead of cutting across the panel with one forceful cut, make many medium-pressure cuts in the same groove.

5. Some flooring like vinyl shows each bump and depression. The staples must be flush a bit below or with the surface of the Luan. The easier way to check is by pulling the edge of your large metal tapping knife on the surface of the Luan.

6. You’ll hear the clicking sound of the metal hitting metal if the staples are sticking up. So, tap the extending staples lightly with a hammer to drive the flush with the Luan surface.

7. Luan is highly secure when fastened to the subfloor properly from the start, either with staples or subfloor adhesive.

8. Sweep and vacuum all the dust plus some particles from Luan underlayment before installing any floor covering surface like vinyl.

Can I Screw Down the Underlayment?

It’s advisable not to use screws when underlayment because it would leave raised spots to crush the wood. Meaning they would all have to be filled and sanded. 

Which Side Of Luan Goes Up?

If you’re installing Luan Underlayment, ensure the smooth side is facing up, and the nails or staples from installing the Luan are hammered down. This ensures a smooth and even surface for the installation of the finished flooring.

Final Thoughts!

Luan is the best and most inexpensive underlayment popularly used to bring out the perfect floor finish like vinyl. Whenever it’s used, the vinyl floor becomes an attractive choice that enables a clean makeover. No wonder they’re the new darlings of interior designers, architects, and people passionate about decoration. It’s great to make use of Luan to get a perfect finish.

But, keep in mind that some manufacturers will not warranty their vinyl flooring if you install it over Luan, especially when installing vinyl tiles. Luan underlayment cannot be used if you’re installing some floor cover finishing. For DIY installation, follow the steps provided in our article.