If your floor is concrete use a concrete grinder for large open areas or a 4 inch or 8 inch angle grinder with a cup wheel attachment made for use on concrete.
How to level a botched concrete kitchen floor.
While concrete is a strong construction material it can still crack.
Grinding and repairing a concrete floor can create concrete dust so be safe and wear a respirator a dust mask will not give you enough protection.
Lay a long level downhill on the floor with one end of the level on the level part of the floor and the other end at the lowest point.
All the kitchen cupboards etc are all firmly in place and it would be one hell of a job to gut the kitchen just to level a floor.
Ive seen self leveling compound my only concern is does the room have to be empty to use this.
When you re finished spread some concrete leveler primer over the floor and let it dry until it has a tacky.
How to repair a concrete floor.
The most important thing is to get the concrete level enough usually level to within a couple of mm per metre or the imperial equivalent for the floating floor.
Deal with a delaminated subfloor.
Tiny variations in that level will be compensated for if you use a good quality foam underlay so there s no need to achieve absolute perfection.
When a subfloor becomes warped or delaminated swells and deteriorates it is no longer level or structurally sound.
See below for a shopping list and tools subscribe to this old.
The only problem is part of the floor is uneven and this shows through the current vinyl.
Leveling a concrete floor.
Then go over any particularly high spots with a concrete grinder so they re level with the rest of the floor.
Temperature changes heavy weights and dropped objects can all damage your concrete floor by causing cracks and holes.
This old house general contractor tom silva shows how to resurface an uneven concrete slab.