This work investigates the pressure amplification experienced behind a rigid, porous barrier when exposed to a planar shock. Numerical simulations are performed in two dimensions using the full Navier-Stokes equations and a M = 1.3 incoming shock wave. An array of cylinders is positioned at some distance from a solid wall and a shock wave is allowed to propagate past the barrier and reflect off the wall. Pressure at the wall is recorded and the flowfleld is examined using numerical schlieren images. Simulations are run for various Reynolds numbers (Re = 500 - 2000) and porosities to determine if they contribute to the pressure amplification. It is found that porosity has a marked effect on the flowfield structure and the endwall pressure, with pressure increasing as porosity decreases until a maximum pressure is reached.