Adding a basement bathroom adds value to the home, but installing toilets and sinks in a below grade environment takes more than a basic knowledge of drainpipes and sewer lines. Transporting waste to the sewer run is challenging because the gravity assist that works for upstairs waste removal will work against waste flow below grade. Fortunately, there are a number of options that fall into the DIY category. New plumbing must meet code requirements, however, so do some homework and consider a ma …