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I have checked out the concrete slab i want to install on and it is slightly off. Not too slightly or i would not ask but the 18 inch level must be raised about 1/2 inch to make level. Is this tolerable? If not, any suggestions on how to fix this? Build a two inch wood platform to set on? Thanks,
An easy way to level the concrete slab is to get a mudjacker to level it. He drills a hole in the low end and pumps in a concrete slurry under pressure. When it's level he seals the hole. Had a fellow come and level a couple of large concrete patio slabs for me :)and it cost about $200.