Abstract: End dam assemblies for sealing a gap between adjacent roadway or deck slabs comprise a series of elongate elastomeric end dam sections which are assembled in end-to-end array. The end dam sections are provided with layers of porous material which confront and engage each other when adjoining end dam sections are secured together. The layers of porous material enhance securance of the end dam sections to each other by providing an auxiliary material on each end dam section which is more easily bonded to the end dam sections and to each other than are the adjoining end dam sections directly to each other. The layers of porous material may also provide mechanical resistance to relative movement of the end dam sections.