When we shut our front doors behind us as we return home, we should do so knowing that we are safe from any outside threats. There should be no fear that our home could come under attack from intruders in the night, or that opportunist burglars may try to break in while we are out. The problem is that not all homes are as safe as we might initially assume. Our front doors aren’t always the strong barriers that they should be – either through their design, poor locks...