How to raise an internal concrete floor by 20mm?

JaseM

Hi there,

I need to raise a concrete floor in a 24m2 bedroom by up to 20mm (mainly 20mm with some 10mm high spots) and am looking at some suggestions on what products to use? Am I better off using a self levelling product for the entire 20mm or a screed of up to 15-17mm and finish with a self levelling compound? I will probably lay carpet tiles over the finished floor. No idea on how much product I need.

Cheers.

JacobZ

Hi @JaseM,

In terms of cost, it would work out cheaper if you were to use screed for the bulk of the filling, with a self-levelling compound over the top, however, I'd need to double check with our suppliers to ensure this is possible. I'm relatively confident it is, but I'd just like to check to be sure I am giving you solid advice.

If you can bear with me, I will get in touch with them when they reopen tomorrow with an answer.

To work out the quantities required, screeds and levelling products will have a coverage rate on their packaging. For example, the Easy Mix 20kg Traditional Floor Screed will cover 1 square metre at 10mm thickness, so you'd need roughly 1.5 bags for every square metre, meaning 36 bags to raise your 24 square metre area by 15mm.

You would then need to use the coverage rate on your chosen self-levelling compound to work out what is required for the last 5mm or so of height. If you used this https://www.bunnings.com.au/dingo-20kg-floor-leveller_p0207213 , which has about the same coverage rate as the screed, so you would need approximately 12 bags.

In saying this, it is always a good idea to have an extra bag or two of each product as it is easy enough to return them if they are not needed.

Let me know if you have any further questions.

Jacob