diff --git a/src/k_terrain.c b/src/k_terrain.c
index dfd059893..1ad7e45a3 100644
--- a/src/k_terrain.c
+++ b/src/k_terrain.c
@@ -415,6 +415,26 @@ void K_ProcessTerrainEffect(mobj_t *mo)
 		P_InstaThrust(mo, mo->angle, speed);
 	}
 
+	// Bumpy floor
+	if (terrain->flags & TRF_STAIRJANK)
+	{
+		/* use a shorter sound if not two tics have passed
+		 * since the last step */
+		S_StartSound(mo, player->stairjank
+				>= 16 ?  sfx_s23b : sfx_s268);
+
+		if (player->stairjank == 0)
+		{
+			mobj_t *spark = P_SpawnMobjFromMobj(mo,
+					0, 0, 0, MT_JANKSPARK);
+			spark->fuse = 9;
+			spark->cusval = K_StairJankFlip(ANGLE_90);
+			P_SetTarget(&spark->target, mo);
+		}
+
+		player->stairjank = 17;
+	}
+
 	// (Offroad is handled elsewhere!)
 }