Hi, we have bought a house recently and uncovered that the floor in our extension is not level. We need it level because we are removing some walls and making the kitchen bigger. We have removed first layer of the floor - some kind of concrete about 10-20mm in thickness went very easily. Now we have another level which is much thicker, around 5-7cm. It looks like concrete and has sort of yellowish colour. It's very hard to destroy but crumbles into almost sandy powder. What is it and what would be the best way to remove it?
If it’s a new extension some builders will use building sand as a blinding to prevent piercing the Dpm . Damp proof membrane. Normally your top layer of screed is between 65-75mm thick on top of insulation, then 150mm concrete base, then 150mm consolidated m.o.t ( Ministry of transport ) Your floor sounds like it has been built incorrectly. The yellow may be the blinding I mentioned .you can level most floors with a latex self levelling product unless building regs have said to remove . Sounds like the oversite needs removing and re doing properly .
The top layer would have been laid to level the floor, the next layer is sand/cement floor screed
The best way to remove it would be with an SDS max breaker this can be hired from any of your local builders merchants/hire centres
Once you get a small piece removed and create an open edge it should be easy enough to remove
It depends on age of the property , the top you have taken off may be a screed and underneath a concrete pad , be aware taking these out you will probably need to put a new DPM in along with insulation , as for getting it out a medium size kango would be plenty powerful enough.
Before you start digging make sure you have have called all utility companies to locate any live services especially as it’s the kitchen area being extended.
Without physically looking there are many reasons why the 2nd is yellow????? or discoloured??????
........but either way not an issue to remove.
If it crumbles as stated then a small electric jack hammer will be enough to break it up or loosen it all for removal.