Viscous fluids exhibits a boundary layer close to rigid walls whose thickness depends on the variation in time. We regard acoustic waves transported in a viscous fluid in perforated chamber. The size and the distance of the holes and the thickness of the boundary layer in comparison to the wave-length motivates a two-scale asymptotic expansion. By matched asymptotic expansion and surface homogenisation the near field solution is given by cell problems around the wall and the far field solution by problems on the limit domain.