The Difference Between Level and Flat – Make Uneven Floors a Thing of the Past

October 2015

“I don’t need a screeder to build a sound, durable sub-floor. Couldn’t my **plasterer do it just as well?” Probably, this was the first thought that popped into your mind when thinking about your new flooring. However, there are a few things to consider in order to get your dream floor. Floor levelness is one of them…read on.

Leveland Flatness Diagrams

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Assessing floor levelness, or departure from datum – defined as the permissible departure of the screed surface from a predetermined reference point, also referred to as datum level – before the installation of the final floor is a critical stage of a flooring project. But what if the surface seems perfectly level and ready to take on the final floor finish? Do you still need to measure departure from datum?

A floor may seem level even if it is not, especially in a large area. How do you make sure that your sub-floor is level then? Although spirit levels can be used to determine floor levelness in a small area or to level certain objects, such as the furniture or kitchen equipment in your home, they are completely useless when trying to assess departure from datum in large rooms.

One reason for this is that the maximum standard length of a spirit level is 1.8m. It is true that a spirit level can be used to check the levelness in different directions against multiple reference points. However, the possibility of error increases with each new reference point chosen. Additionally, the profile of a spirit level may become bowed, distorted, or warped over time, which can lead to inaccurate results.

The only way to assess levelness accurately is to use an electronic laser level and measure deviations against a single reference point. To get a level and flat screed layer for your new flooring, it is important to call in a professional screeder, who not only knows how to use advanced laser levels to measure departure from datum but also can come up with the best solutions to correct potential levelness issues.

If you are looking for a reliable floor screeding contractor ready to take a hands-on approach to your project and nurture a collaborative relationship with you, whilst providing the best services to the community it lives and works in, contact us at HomeScreed. Our team of dedicated professionals provides a wide range of services, from free advice and guidance on underfloor heating and screeding to screed installation and testing.

** Please note we are not knocking plasterers, and why would we? Our MD started out as a plasterer. All we are trying to say here is that you should work with professionals who actually master the art of screeding.