The importance of leveling your subfloor Unevenness can cause planks to flex or gap, leading to an unstable surface that's prone to squeaking and damage. It can also compromise the locking mechanism of laminate planks, causing them to come apart over time.
The subfloor must be level before installing laminate flooring. If the subfloor is leveled, the laminate planks will not lay properly, causing uneven and unsightly floors. If the subfloor is not level, you can use a self-leveling compound to level it out.
Installing laminate wood floors on an uneven floor requires proper preparation to ensure a smooth finish. Start by identifying the uneven areas using a level. For minor dips or humps, use a floor-leveling compound to even out the surface.
Most manufacturers recommend that the floor be flat to within 3/16” in a 10 ft. radius. These measurements are consistent with most other types of floor coverings. On floating floors, vertical movement needs to be kept to a minimum.
No subfloor is perfectly level, but any signs of unevenness and high or low spots must be remedied. Please follow these requirements: Subfloor unevenness cannot be greater than 3/16 of an inch over a 10-foot span or 1/8 inch over a 6-foot span.
Use an underlayment, floor leveler or floor patch product to fix low spots in a wood or concrete subfloor. An underlayment is a thin layer of material sandwiched between two other materials. It's used to help insulate, absorb sound and reduce wear on your floor. It can also serve as a vapor barrier.
Please note that most manufacturers require a level subfloor with a tolerance of 3/16” every 10 feet. While no floor is perfectly level, the subfloor should be checked for any noticeable gaps or ridges that could cause problems.
Self-Leveling Compound: For larger areas or more significant unevenness, a self-leveling compound can be used. This pourable compound spreads across the floor, filling in low spots and creating a smooth, level surface. Follow the manufacturer's instructions for mixing and application.
The Standard simply defines the required flatness of a concrete subfloor. The subfloor, or 'underfloor' as I like to call it, “shall not deviate more than 3/16 of an inch in ten feet.” Photo 1 shows a ten straight edge being used to gauge the undulation of the floor.
Laminate is a floating floor, meaning it lays loosely over your subfloor. The laminate panels need to be evenly distributed and fixed securely in place, so they don't move or warp. A lot of subfloors are slightly uneven or bumpy, which can affect the quality of the laminate installation.
If you're wondering what's the best underlay for laminate or wood flooring, Fibreboard is a brilliant choice. It helps smooth uneven floors, reduces noise and acts as an excellent thermal insulator. Not to mention, it's also the number one choice of underlay for laminate and wooden floors.
When your laminate flooring warps, it will be twisted and uneven. It's almost always caused by moisture problems. Moisture can migrate up through the subfloor. Even if the top surface of the laminate is designed to be waterproof, the bottom is not, and that's what the moisture will hit first.
Before you lay laminate flooring, you need to make sure that the subfloor is level. If the subfloor is uneven, the laminate boards will not lie flat, resulting in gaps and bumps. The good news is that it is possible to level an uneven subfloor before installing laminate flooring.
In some cases, carpet may be the best flooring choice for uneven floors. The proper procedure for fitting LVT is to ensure that the subfloor is flat before laying your LVT on top.
You have the top layer that is your floor covering (Hardwood, Laminate, Vinyl, Carpet, etc.), next you have the underlayment (usually a thin layer of fiber, foam, rubber), below that you have your subfloor (plywood, OSB, concrete), and lastly you have the joists which are the foundation to your floors.
A subfloor needs to be clean, dry, level and structurally sound. Use a level to determine if the floor is level within 3/16-inch change per 10 feet. Mark any high or low spots with a pencil or marker. If you're gluing the new floor to the subfloor, use a sander to remove oil, wax, paint, adhesives or other materials.
The secret to a perfect laminate floor. The sub-floor has to be absolutely flat - 90% of your worries will then be over. Don't scrimp on the screeding; this is the whole secret to a long lasting trouble free floor.
For parts under 36” in both width and length, flatness should not exceed ¼”. For parts whose length is between 36” and 72”, the flatness variation should not exceed 75% of the flatness of a 10' sheet for that given width.
You'll need to know how to level a floor: Just sand any high spots and fill the low spots with leveling compound. A floating floor (laminate or locking hardwood) shouldn't be installed over a wood subfloor that's adhered to a concrete slab. Check the moisture level of the subflooring using a moisture meter.
Step 4: Use a flooring underlayment to smooth out any remaining inconsistencies. A flooring underlayment can help to smooth out any remaining peaks and valleys in the subfloor and prevent problems down the line. However, remember that an underlayment can't work miracles, so don't count on it as your only solution.
If there's excess moisture within the subfloor or the concrete slab on which you're laying the flooring, the laminate may not lay as flat as you'd like. If it's more than 6-9% damp, you may need to use a dehumidifier or try to dry out the area before the floor can be laid.
Buckling or Warping – Laminate flooring is not waterproof. If you fit laminate in wet or moisture-rich areas, the floor can become damaged, often beyond repair.
Just like ceramic tile, wood and resilient flooring require a high degree of flatness that can easily be achieved using a cementitious SLu. Many manufacturers of wood flooring require that the variation in floor flatness be no more than 3/16" in 10' and 1/8" in 6'.
Prep Floor
The base floor should be clean, level and smooth. If needed, fix concrete subfloors with a patching compound. For wood subfloors, remove protruding nails and replace any damaged boards. uneven floors, use a foam underlayment as the base for your laminate planks.