Share
Hi all, I am converting an old shed to an office. The existing concrete floor is quite cracked and has a reasonably substantial rise in the middle of the floor ( approx ~23mm from the high point to low point in the corner of the room).
The room dimensions are 2.3 x 3.1 and my original plan was to apply the self leveller (https://www.bunnings.com.au/lanko-20kg-173-floor-leveller_p0966696) up to the high point in the room but after doing a bit of reading I have a few questions.
- The existing floor is painted, do I need to remove the paint first or can I apply the primer directly on top (see pics)
- If I apply the leveler to the high point in the room I am worried the leveller will be so thin at the high point it may/will crack. WOuld it be better to grind down the high point a bit?
- Can the leveler be applied directly over cracks without patching?
Thanks in advance!
Hello @mjcollins1180
Welcome to the Bunnings Workshop community. It's sensational to have you join us, and thanks for sharing your question about levelling your concrete floor.
You are correct, the paint will need to removed in order for the self-levelling compound to properly adhere to the concrete floor. Between a mechanical and chemical method of stripping, I suggest doing a mechanical stripping by using a Josco 75mm Cup Brush. Please remember to wear personal protection such as appropriate clothing, gloves, goggles and a heavy-duty mask. Using this tool will create a lot of dust and debris so make sure to warn everyone away while you are using it. Chemical stripping is sometimes not as effective, and you end up stripping some sections off with a wire brush head. Plus, disposal of the stripped paint is quite often messy.
Once you've removed the paint you can now concentrate on levelling the high point of the concrete floor. I suggest hiring a For Hire: Coates Self Levelling Floor Grinder - 5+ Days. This will grind away your uneven floor and give you a nice even surface to level. Once you have grinded the surface, I suggest using Earl's 500g Concremate Expanding Cement to patch all the cracks and damages to the floor. Make sure to give your floor a proper wash to remove all the dust and debris before you apply the self-levelling compound.
If you need further assistance, please let us know.
Eric
