It is important to have noise reduction especially for second floor installation.
I understand that there are ratings for noise reduction like Impact Noise Rating (INR), Sound Transmission Class (STC), Impact Insulation Class... I understand, the higher the number, the better it is.
What is the Best Sound Isolation underlayment available for ceramic tile flooring?
Check a new product from Custom Building Products called EasyMat. Other than that, there are several companies that put out a cork underlayment made specifically for sound deadening. But they all require specific tile installation instructions do to the compressive nature of the cork underlayment.
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