Prep your subfloor so that it's clean, dry and level within 3/16-inch change per 10 feet. Use a self-leveler on low spots and/or sand high spots of wood or concrete. Don't sand vinyl flooring as it may contain asbestos.
Planks installed on an uneven floor can also lead to hollow spots, bouncing floors, and flooring joints separating, breaking, or splitting, causing the floor to fail. Tip: Use a level or straight edge to ensure the floor is flat before installing your vinyl.
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. Subfloors must not slope more than ½ inch per 6 feet (25 mm per 1.8 m) Subfloors must be structurally sound.
It is absolutely essential that the subfloor is completely level. The preparation of the subfloor depends on what type of vinyl you are installing. Make sure the subfloor is completely flat. Any unevenness of more than 0.2 mm over a length of 20 cm must be levelled out.
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.
In some cases, a slight slope may be normal and not cause for concern. However, if the slope is severe or getting worse over time, it could be a sign of a serious problem that requires immediate attention. One potential risk of sloping floors is damage to the structural integrity of the home.
Floating flooring is not recommended for uneven floors as this increases risk of the planks moving or splitting apart. Ceramic and porcelain tiles will also crack over time if the subfloor is uneven.
Forgetting to level the subfloor
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.
Epoxy. If you have uneven floors, flexible flooring like epoxy is the best choice. This is because the epoxy self-levels itself and covers the entire floor evenly.
Subfloor Preparation:
Subfloor should be flat within a tolerance of 1/8” over a span of 4 feet. Any unevenness over 1/8” must be sanded down or filled with a floor leveler. Voids or humps in the subfloor will prevent luxury vinyl from locking properly.
Vinyl flooring naturally expands and contracts in the heat and cold. Stop the floor between a quarter inch and a half inch shy of the wall to allow for this natural expansion. If the floor is installed flush with the wall there is no room for growth in the hot months and the loose-lay floor can easily buckle.
Luxury vinyl flooring is more forgiving than other types of hard flooring when it comes to installation on a subfloor that is less than perfect. If you attempt to install ceramic or natural stone tile on a subfloor that is not well prepared, with no bumps, blemishes, cracks, or warping, every imperfection will show.
The easiest way is to use a self-leveling compound, also called liquid floor underlayment or floor resurfacer, within sections of level-cut rails. The material flows out like thick syrup, then hardens into a smooth, perfectly level surface, sometimes in less than an hour.
When properly used, expansion gaps can relieve the pressure from heat expansion that can affect a floating floor and prevent any noticeable buckling or peaked appearance. If the floor is less than 50 ft in length or width, leave at least a ¼-inch expansion gap around the entire perimeter.
In short, vinyl flooring itself can be completely self sustainable and does not require an underlayment to function properly. Another reason underlayments may be suggested for vinyl flooring is if the vinyl flooring type is thin. When the vinyl flooring is thin, it becomes a lot easier to flex and bend.
Underlayment can help smooth things out, though, but the type you choose will vary depending on your specific reasoning for wanting an even subfloor. That can make choosing the right one for you rather tricky, so here's a quick guide that should lend a helping hand in getting the best underlayment for uneven subfloors.
For only slightly uneven flooring, sturdy materials such as luxury vinyl plank can also be used for full coverage. The benefit of sturdier types of flooring is that they will give the floor the illusion of being more even than it actually is. For very uneven flooring, laminate sheets or tiles may be a better bet.
As mentioned above, it's common to find slanted floors in a house more than 15 years old due to the home's foundation shifting over time. However, the uneven floor may be an indicator of a larger, unseen problem with the house.
Underlayment can serve as a relatively simple fix to an uneven-subfloor. Keep in mind that in some circumstances you won't be able to use underlayment as underlayment should only be used for minor imperfections.
While laminate tends to be more forgiving of subfloor imperfections compared to other types of flooring, it is still important to level your flooring to avoid future damage if you are installing laminate flooring on an uneven subfloor. A level subfloor ensures a more attractive and long-lasting finish.
The main things that you need to consider when choosing the thickness of your laminate floor are the evenness of your subfloor and any reason you may have to be worrying about noise reduction. If you have a subfloor that is in any way uneven, it pays off to choose a thicker laminate.
Fibreboard underlay
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. If you have an uneven subfloor, the fibreboard will help even any dips and dents you can't level out.
Expansion gaps are essential in all laminate floor installations. Temperature and humidity will change in all rooms.
Always do a once-over of the flooring surface before you lay your laminate, ensuring there is no more than a 1/8 of an inch tolerance. You might need to grind or sand the flooring surface down before you lay your flooring for the best end results.