A vapor or moisture barrier is a layer of protection that is designed to act as a waterproof shield helping to keep condensation away from wood insulation and other mold prone materials that are located behind the drywall.
													
																	Wall tile vapor barrier. 
									
	
		
	
																	It s usually a thin layer of plastic that sits between the drywall and the studs. 
																	A vapor barrier can be applied or installed over the tile substrate using a liquid or sheet membrane. 
																	There is a clear advantage of using a liquid membrane it is relatively easy to apply over the tile substrate along with the use of a fiber mesh tape you can secure joints and changes of plane. 
																	Nance carpet and rug versapad 180 sq. 
															
													
									
	
		
	
																	Over time this will present itself as unhealthy mold and rot.