These few laminate flooring subfloor tips will save you time, money, and aggravation. From the start, the subfloor type and its proper preparation should be at the top of your to-do list when installing a new laminate floor. Failure to properly prepare a laminate flooring subfloor results in a large percentage of laminate flooring failures.
Laminate Flooring Subfloor an Important Consideration
When purchasing laminate flooring, always obtain and read the installation instructions for the floor you are purchasing. Not all laminate manufacturers have the same laminate flooring subfloor requirements.
Flat and Level Laminate Flooring Subfloor
Most but not all laminate floor manufacturers require a subfloor to be flat within 3/16″ over a 10 foot radius. Other manufacturers will have a different requirement though flat and level is a common requirement within the laminate flooring industry.
Some manufacturers instructions will use the word level instead of flat, read between the lines as they are usually speaking of the laminate flooring subfloor being free of high or low spots.
A subfloor that does not meet the laminate manufacturers installation requirements must be leveled by sanding or filled with an approved floor patching material.
On a floating floor gaps can easily develop between planks when a subfloor is not level.
Unfortunately as flooring inspectors we see many installations where the person installing the floor claimed to be an expert but did not install the floor as required by the manufacturer. Failing to follow the manufacturers installation instructions is a huge laminate floor problem as it often voids the warranty.
Tips for Preparing Laminate Flooring Subfloor
Concrete as a Laminate Flooring Subfloor
- Perform a mat test to check for moisture. Follow the manufacturer’s instructions for any additional moisture testing. They may require a Calcium chloride test or an in-slab RH test.
- New concrete needs to cure for a minimum of 60 days.
- Use an approved vapor barrier. Most companies require a vapor barrier even when the floor is covered by vinyl, linoleum, tile or sheet flooring.
- Grind down high areas or us a self leveling filler to fill low areas.
Wood & Wood Composition Flooring Subfloor
- Test for moisture content and make sure it is no higher than the laminate manufacturers requirements.
- Make sure that the subfloor you are going to install your laminate over is flat and level within the laminate manufacturers requirements.
- If you have movement in the subfloor correct it before installing your laminate. A laminate flooring subfloor is difficult to correct once the laminate has been installed.
- Check your crawlspace. Make sure you have a proper vapor retarder covering the entire area of soil in the crawlspace. Check for standing water or wet soil. If you have standing water or wet soil this presents a future laminate problem.
- Use the proper cushion between the laminate and the subfloor but do not use a vapor barrier over a wood underlayment.
Vinyl or Linoleum as a Laminate Flooring Subfloor
- Usually make a good laminate flooring subfloor if they are clean and level.
Ceramic Tile or Stone as a Laminate Flooring Subfloor
- Removal of ceramic and stone is generally not required. A good laminate flooring subfloor. The floor must be flat within the laminate manufacturers requirements. A vapor barrier will likely be required, especially if the tile is over concrete.
Over-Wall-to-Wall Carpeting
- A laminate floor should never be installed over a carpet installed over a cushion. Some laminate flooring manufacturers may allow you to install your laminate flooring over a tight, thin, level loop, glue-down carpet. You will also need to check with the manufacturer of the laminate flooring product to determine if the glue-down carpet will be accepted as a laminate flooring subfloor.
While these tips are basic, if you follow these laminated flooring installation tips, you may just save yourself a future laminate floor failure.
Need Help? Get an Expert Laminate Flooring Inspection
Avoid costly mistakes in choosing and installing laminate flooring. If your flooring has experienced failure, TW Group Flooring Inspection can help with inspections and consultations. Contact 800.621.3427 or submit an online inspection request.
✅ Request an inspection here: Schedule a Certified Flooring Inspection
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