SPC flooring can be laid directly on concrete floors, but the concrete floor must meet certain conditions; otherwise, the installation effect and lifespan will be affected.
Core Requirements for Concrete Floors
Levelness Requirements:This is the most critical condition. Using a 2-meter straightedge and wedge gauge, the height difference of the floor should not exceed 3mm. If the floor is uneven, the flooring is prone to warping, squeaking, and even breakage after installation.
If the floor is not level enough, it needs to be leveled with self-leveling cement first, and then laid after it is completely dry.
Dryness Requirements The moisture content of the concrete floor needs to be controlled below 3% (the requirements vary slightly between different brands of SPC flooring; refer to the product instructions). Excessive moisture will cause water vapor to rise, causing the flooring to bulge and warp.
A simple test can be used to determine this: Lay a plastic film on the floor, seal the edges, and observe whether there are water droplets inside the film after 24 hours. If water droplets are present, the floor is damp and needs ventilation and drying or moisture-proofing treatment.
Clean and Solid: The subfloor must be free of dust, oil, sand, hollow spots, or loose cement blocks. Oil stains will affect the adhesion of the flooring (especially self-adhesive flooring), while loose particles will cause uneven stress on the underside of the flooring.
A thorough cleaning is required before installation. Stubborn stains can be cleaned with a specialized cleaner. Hollow areas must be removed and repaired.
Specific Installation Procedures for Two Methods:
Click-lock SPC Flooring (Mainstream Model):
No glue is needed. First, lay a moisture barrier on the cement floor (generally 2-3mm thick, providing moisture protection, sound insulation, and cushioning).
Simply interlock the SPC flooring pieces using the interlocking mechanism. Leave a 5-8mm expansion joint (at corners, doorways, etc.) to accommodate thermal expansion and contraction.
Self-Adhesive SPC Flooring:
No moisture barrier is needed. The subfloor must be even cleaner and flatter. Simply peel off the protective film from the back of the flooring and adhere it to the cement floor.
After pasting, press it firmly with a heavy object to ensure a tight fit and prevent curling.
Additional Notes
If there are cracks in the cement floor, fill them with repair mortar first before proceeding with the next steps.
In damp areas such as basements and ground floors, it is recommended to lay an additional layer of waterproof membrane under the moisture-proof mat to enhance moisture protection.
