If you're new to using a self-leveling compound, we recommend hiring a professional to do the job for you. Working with polymer-modified cement that has a high flow capacity can be challenging, and it's best left to those who are highly confident in their DIY skills. However, if you're determined to give it a try, we've put together this step-by-step guide to help make the process as straightforward as possible.

How to Lay Self Leveling Compound

Self leveling compound works on all types of substrates, including screed, concrete and even existing tiles and timber. It's great for uneven floors. However, there are various preparation methods required to make sure the end result is smooth and flat.

First, check how uneven your floor is, as a floor leveling compound isn't ideal for discrepancies greater than 5mm. An easy way to assess this is by using marbles or other smooth balls. Drop them at various points on your floor to identify the deepest dips. Next, take a 6ft spirit level and place one edge in the dip. Lift the other side until the bubble is centered. Then, use a ruler to measure the resulting gap. If it's more than 5mm, you'll need to find an alternative method to level your floor.

Tools you'll need for the job

Scraper

Filler

Duct tape

Primer

Self leveling compound

Mixing paddle

Large bucket

Steel trowel

Spiked roller

A sturdy drill

How to Use a Self-Leveling Compound

Prepare the Substrate

Once you're sure you can use a self-leveling compound, your next step is to prepare the substrate (base) of your floors. Use a scraper and a hard-wired brush to remove any dirt and debris, then sweep and vacuum thoroughly.

To prime your floor, start by cleaning it to remove contaminants such as floor paint, adhesives, and laitance. This prevents the compound from bonding to these materials instead of the substrate. If your floor is silky smooth, roughen it slightly to ensure a stronger bond with the compound.

After cleaning and roughening the surface, apply a floor primer and let it dry overnight.

Mix the Compound

Take your bucket and follow the instructions on the self-leveling compound package. Typically, this involves adding a specified amount of cold water first and then slowly introducing the compound. Use a mixing paddle or electric mixer to blend the mixture until it's lump-free and has the right consistency.

Top tip: Add water gradually to avoid extending the drying time of your compound.

Pour the Mixture

Once the compound is ready, begin pouring it onto the floor starting from the farthest corner of the room and work your way backward. Use a steel trowel to spread the compound evenly in sections. Follow up with a spiked roller to eliminate any air bubbles. Continue this process until the entire floor is covered, smooth, and free of bubbles.

Leave to Dry

Ensure the room is well-ventilated and maintains a temperature of around 20 degrees Celsius. Avoid exposing the compound to strong sunlight or cold drafts, as these can cause uneven drying and lead to issues like cracking or crazing. If you have underfloor heating, make sure to use a latex polymer compound to accommodate the heating system.

How Long Does a Self-Leveling Compound Take to Dry?

Depending on the compound used, drying can take between one to six hours. However, it is recommended to leave it overnight to ensure it fully settles before walking on it.

How Does Self-Leveling Cement Work?

Self-leveling compounds are spread in thin layers to level floors, relying on gravity to even out the surface. They provide flexibility to concrete, allowing it to move without cracking.

How to Use Self-Leveling Compound Over Tiles

To pour self-leveling compound over tiles, first thoroughly clean and abrade the area. Then, follow the same steps outlined above to achieve the desired results.

How Much Self-Leveling Cement Do I Need?

The amount of self-leveling compound required depends on the square footage of the room you are leveling. For instance, a 20lb bag of self-leveling compound typically covers approximately 20 square feet at a thickness of about ⅛ inch.

How to Mix Self-Leveling Compound

To mix self-leveling compound, use a large bucket and either a mixing paddle or an industrial electric mixer. Follow the manufacturer's instructions to achieve the correct consistency and ensure the mixture is free from lumps. Control the water-to-powder ratio carefully, using clean and cold water (avoid warm water, as it can affect the product's performance).

How Thick Can You Lay Self-Leveling Compound?

Self-leveling cement is generally used on floors with uneven surfaces up to 5mm. Typically, it results in a thickness of about an inch. However, some variants of self-leveling compound can achieve thicknesses of up to 5 inches.

FAQs

How Do You Lay a Self-Leveling Compound?

You can either hire a professional for guaranteed results or follow our step-by-step guide above. Keep in mind that the results are permanent and difficult to reverse, so ensure you're confident in performing this task yourself before proceeding.

How Do You Prepare a Floor for Self-Leveling Compounds?

Prepare the floor by thoroughly cleaning, sweeping, vacuuming, and applying a primer.

Do You Need to Use PVA Before Self-Leveling?

There's no requirement to use PVA before applying a self-leveling compound. However, it's recommended to clean and prime the surface before pouring the compound mixture.

Can You Lay Self-Leveling Compound in Layers?

Yes, you can lay self-leveling compound in layers. Ensure each layer is cleaned, primed, and abraded before applying the next.