Luan Underlayment: When And How Do You Install Them

Last Updated on August 26, 2021 by Emma W. Thomas

Luan is a thin plywood underlayment material used under resilient flooring materials like vinyl, linoleum sheets, and sometimes tile. They provide a smooth and flat surface for maintaining a professional-looking floor finish. Improperly installed Luan underlayment leaves surface imperfection popular with subflooring.

Luan underlayment is best for resilient flooring materials like linoleum and vinyl. To install, first determine the size of your floor and clean it. Now, cut the laun based on floor size and lay it perpendicular to the subfloor with at least 1/8-inch space between them. Leave 1/4 –inch space between the cut edges and the wall.

Read through our article to install it successfully. 

Luan plywood underlayment is ¼ inch thick; they are instances where it’s only 1/8 inch thick instead. It comes in 4-by-8 sheets. Sometimes they are spelled as lauan plywood. Luan plywood underlayment is hardwood plywood made from tropical trees like mahogany found in southern Asian countries. 

Luan is manufactured by layering the thin strips of mahogany first at correct angles and then bonding them together under pressure to form large panels. All Luan panel has a smooth side and a rough side. While installing Luan, the smooth side faces upward as an underlayment.

There are several different appearances of Luan, mainly in both red and white colors but relatively similar.  The appearances depend on where the tropical were harvested and the manufacturer.

Luan Underlayment

When To Use Luan Underlayment

Many homeowners and potential ones are interested in the idea of using Luan to replace traditional plywood subflooring since they are readily available. Also, they are less expensive compared to traditional plywood or OSB subfloors. 

Unfortunately, Luan plywood is not a substitute for the standard 3/4 –inch plywood, which many homes need for their subflooring. But, it doesn’t mean you cannot use Luan plywood as part of the home process.

Nowadays, you can easily find conflicting advice about underlayment, especially Luan plywood. Hardware that sells underlayment often claims it fits resilient flooring, plush carpet, tiles, and hardwood, totally every type of flooring.  But the fact is adequately installed plywood subfloor gives a perfect installation surface for Luan underlayment. This enables suitable surfaces for most flooring materials like luxury vinyl planks, usually thicker than traditional vinyl tiles.

Plywood underlayment isn’t a better choice for stone tile or ceramic since it is not water-resistant. Therefore it’s good for any floor tile room to use a cement board or tile backer instead. 

Use plywood underlayment if the flooring manufacturer recommends it. You may need a warranty for its usage. If a flooring material needs to have a flat and smooth surface, use plywood materials. For example, the installation of resilient tiles, sheet flooring over a subfloor, any dips, bumps, or voids in the subfloor may be visible in the finished flooring. For the best result possible, use underlayment to cover subfloor flaws.

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 measurements 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 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 smooth 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.

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 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 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.

Leave a Comment