There should be something to rely on behind the sofa.
There should be a support behind the sofa, that is, a backing, which means that there is a solid wall behind the sofa and there is no worries. This is in line with Feng Shui.
Sofa should avoid the top of the beam.
The sofa must avoid the top of the beam. If it is really unavoidable, two pots of lucky bamboos can be placed on the coffee tables on both sides of the sofa to bear the growing and rising lucky bamboos.