Many floors, particularly in older houses, are uneven. It’s not until you try to install a new floor cover that you realise how much the subfloor beneath has warped or moved. Some people might want to jump right into installing their new laminate floors without assessing the floor beneath. For this reason, I have outlined if you can actually install laminate on an uneven floor.
Laminate can be installed on an uneven floor; however this can degrade the quality of your new laminate. The finished product may become warped as a result, causing the floor to shift and become damaged when walked on. For this reason, it is best to level the subfloor prior to installing laminate.
I will discuss in more detail reasons why you should not install laminate on an uneven floor. It is also crucial to understand how a floor can be levelled and how this differs for subfloors made of concrete or floorboards.
Can You Install Laminate on an Uneven Floor?
It is definitely possible to install laminate on an uneven floor, however it is not recommended. Laminate is installed by laying interlocking sheets over the floor beneath, which is known as the subfloor. These sheets are not attached to the subfloor, but simply rest on top of it.
However, if you leave the floor uneven before laying the laminate, there will be many issues with the quality of your laminate flooring. I will discuss these in more detail below.
Most uneven floors are caused by dips and bumps in the subfloor as it moves and warps over time. This is why older houses are more susceptible to uneven floors.
Sometimes the floor may be flat, but slopes to one side. This is also an issue, but is caused by structural problems with the house. Structural issues are harder to fix, so may require professional work.
If you do not take the time to check the levels of the subfloor, or you don’t realise that it’s uneven, you are at risk of ruining your new laminate floor as it settles over the uneven surface.
It is therefore best to correct any uneven areas in your floor before installing laminate over the top.
Should You Put Laminate On an Uneven Floor?
You should not put laminate on an uneven floor. This will reduce the quality of the finished product and waste your time. However, laminate usually comes with underlay, which will compensate for any smaller discrepancies.
If there are bumps or dips that are more than 3/16 of an inch in size, you should not lay laminate until the floor has been levelled. Laminate that is installed on an uneven floor will settle into the uneven surfaces. This will affect the quality of the final product.
The dips in the subfloor will create an air gap under the boards, which is what causes laminate floors to pop and creak under your feet. This could also damage the interlocking mechanism that connects each laminate board and create gaps between them.
An uneven surface can also warp your new laminate, causing areas to lift. This might be just enough to trip on or to start wearing away the edges of the boards.
There is nothing stopping you from installing a new laminate floor on an uneven floor, but the poor quality of the finished product would not be worth your time and money.
With the right tools, uneven floors can be easily levelled. So there’s no reason why you shouldn’t give it a go.
How to Lay Laminate on an Uneven Floor?
There are a few things to consider before laying laminate on an uneven floor. You will need to have the right tools and prepare the area before making any attempt at levelling the floor and laying your laminate.
Vacuum cleaner: You will be using this to clean dust and dirt from the subfloor. You could use your normal household vacuum, but just keep in mind that any loose staples, nails or wood chips could damage it.
Carpenter’s level: Also known as a spirit level. This is an instrument that is designed to determine if a surface is level. It has liquid in one or multiple tubes, with a small air bubble within. When the level is placed on even ground, the bubble will sit in the middle of the tube.
Self-levelling compound: Usually a watered-down form of concrete that covers the subfloor, creating a level surface with gravity.
Wide putty knife: A wide, blunt and somewhat flexible knife that is used to smooth thick material over a surface. In this case, it is used to even out the levelling compound or spread a small amount over a small dip in the floor.
Sandpaper: You can use sandpaper on wood subfloors if there are minimal bumps in the floor. You should use 80-120 grit sandpaper.
Hammer: Make sure you have a hammer with a claw. This will allow you to remove nails.
Finishing Nails: These are long thick nails that secure your laminate or wood in place, if you choose to do so. You can also nail down any loose floorboards underneath the laminate.
Preparation for Fixing an Uneven Floor
Fixing an uneven floor doesn’t have to be hard. But preparation does make a big difference in the final product.
Firstly, you will need to remove the old floor covering, such as carpet, to expose the subfloor beneath. The subfloor can be made of concrete, floorboards or chipboard. Make sure to remove any exposed staples or loose nails.
Regardless of what your subfloor is made of, you should use a vacuum to clean up any dust or dirt that has accumulated. This is a requirement of using a levelling compound.
Next you might want to consider removing your skirting boards. These may be the wrong height after you have levelled the subfloor and put a different floor covering on. It’s also easier to press the laminate boards against the wall without the skirting boards in the way.
How to Fix/Level an Uneven Floor for Laminate
The first step to fixing your floor is identifying where the dips and bumps are. This is done using the spirit level. Run the level slowly across your floor to see if there are any areas that shift the bubble within.
Alternatively, you can use one of the laminate floorboards. Hold the board on its side on the subfloor. Check that the full length of the board is in contact with the floor. If not, you will be able to see which areas are raised and which have dips.
Levelling an uneven floor is slightly different depending on which type of subfloor you have. I will explain the process for each type.
Fixing Uneven Concrete
For uneven concrete, you will use the concrete self-levelling compound. This comes in a pre-mix, which you will need to add water to. Once you have added enough water to make it quite runny, it will be ready to pour over the subfloor. A self-levelling compound should be poured over the entire subfloor until every area is covered.
This will ensure the floor is level. However, if there is just one small dip in the concrete, you might prefer to just fill in that small area. Once you have poured the mixture over the dip, you can smooth it over using a wide putty knife.
You will need to wait for the levelling compound to cure, which takes approximately 24 hours. Once it has, you can recheck the levels for peace of mind, but you should have a self-levelled floor to work with.
Fixing Uneven Floorboards or Chipboard
If you have floorboards, you may need to check for any loose boards before levelling the floor. You can do this by walking over every area of your room and feel for any shifting, or listen for any creaks and groans.
Once you have secured these boards with nails or screws, you can look for uneven areas. If the uneven area is because of a few floorboards lifting, it is easier to just replace those boards.
If you are levelling the entire area, you will need to waterproof the whole floor. This means using caulk to seal each joint between the floorboards and a sill seal with the caulk to seal the perimeter of the room. This ensures that the liquid levelling compound does not seep out the room or down into the joists.
Once you’re sure the floor is watertight, you can pour the levelling compound over the entire area and wait 24 hours for it to cure.
After you have levelled either your concrete or wooden subfloor, you can begin laying your new laminate floor.