My company specializes in kitchen and bath remodels, so we install a lot of tile floors. We sometimes have to begin the job by addressing structural deficiencies in the floor. But even sound wood subfloors and concrete slabs may not be flat enough for tile - a problem we most often solve with a self-leveling cement underlayment, or SLU.
SLUs can be poured to a feather edge, so they're well-suited for smoothing out uneven, poorly finished slabs. They can also be used to fill low spots, making them a good choice for fixing sagging, out-of-level wood-framed floors. And SLUs are fast: We can usually prep and pour the underlayment in one day, then come back and start installing tile...
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