the panels 100 and emplacing a topmost section 313 to encapsulate the panels 100 implements a fluid barrier within porous material preferably durable porous material such as concrete refer to fig3 a in one preferred method the adhesive 312 may then be allowed to u201c set u201d or cure prior to installing a finish layer 313 over the plate or foil 100 not all methods may require curing of the adhesive 312 prior to the finish step however the finish layer 313 may be a poured fluid such as concrete such that the concrete oozes into the spaces between the channels 101 as shown at 314 thus facilitating a strong bond between the plate or foil 100 and the finish layer 313 for those underlayments 311 that are exposed to heavy traffic including hard wheeled vehicles for example the finish layer 313 may be relatively thick concrete in one preferred embodiment the result is a multi layered configuration 310 that achieves an effective moisture and vapor barrier to fluid ingress from beneath the underlayment 311 while permitting heavy traffic on its concrete finished surface 313 the method of emplacing a fluid barrier within porous material extends to establishing a vapor barrier in porous material the vapor barrier may be a one way barrier such that the configuration is permitted to u201c breathe u201d or u201c outgas u201d in one direction while establishing and maintaining a fluid barrier in the opposite direction in a preferred embodiment of.