--- ../src-base/minecraft/net/minecraft/block/BlockStairs.java
+++ ../src-work/minecraft/net/minecraft/block/BlockStairs.java
@@ -483,6 +483,29 @@
         return new BlockStateContainer(this, new IProperty[] {field_176309_a, field_176308_b, field_176310_M});
     }
 
+    @Override
+    public boolean doesSideBlockRendering(IBlockState state, IBlockAccess world, BlockPos pos, EnumFacing face)
+    {
+        if (net.minecraftforge.common.ForgeModContainer.disableStairSlabCulling)
+            return super.doesSideBlockRendering(state, world, pos, face);
+
+        if ( state.func_185914_p() )
+            return true;
+
+        state = this.func_176221_a(state, world, pos);
+
+        EnumHalf half = state.func_177229_b(field_176308_b);
+        EnumFacing side = state.func_177229_b(field_176309_a);
+        EnumShape shape = state.func_177229_b(field_176310_M);
+        if (face == EnumFacing.UP) return half == EnumHalf.TOP;
+        if (face == EnumFacing.DOWN) return half == EnumHalf.BOTTOM;
+        if (shape == EnumShape.OUTER_LEFT || shape == EnumShape.OUTER_RIGHT) return false;
+        if (face == side) return true;
+        if (shape == EnumShape.INNER_LEFT && face.func_176746_e() == side) return true;
+        if (shape == EnumShape.INNER_RIGHT && face.func_176735_f() == side) return true;
+        return false;
+    }
+
     public static enum EnumHalf implements IStringSerializable
     {
         TOP("top"),