Actually, floors are constructed with two layers. The concrete layer and then 2" thick of sand sreeding. Concrete layer is structural and usually we don't see it. Sand screeding is the smooth surface that we could see before tiling and timber floor. This layer covers the concrete layers.

Usually, it is the sand screeding layer that will have crack due to the mix ratio for the sand and cement or the preparation work. Usually, before sand screeding, the concrete layers must be clear of dusk and should be wet. If all these are not done properly, you could hear the empty sound.

So, my suggestion before repairing, buy one drum hammer and do the tapping test to see whether there are other areas that have so called "empty". Usually, this type of empty (i.e. the cement and sand are not bonding) will cause the tidy gaps, which eventually develop into cracks.

After identifying areas affected, then better get the contractor to quote.



This post has been edited by ongss: Dec 20 2024, 12:39 PM