Should i use red guard over backerboard within shower? i'm going to put up 6 mil vapor barrier consequently cement...

i'm going to put up 6 mil vapor barrier consequently cement board...should i use redguard over the cement board or could this be bad because it would almost be approaching a second vapor barrier?
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Answers:    i would not use nil over cement board because your going to put tile against cement board and the tile might not stick,hope that helps.
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no you should not. Either use redgaurd or a vapor barrage not both. Red Guard is a great product. The backerboard should go over the vapor barricade or Red Gaurd.
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