This my seem like a simple question.  It is your house and shelves and cabinets are easy to build.  What is the big deal?  Why even ask such a question?

From the home inspector’s point of view, it depends.  Generally, as home inspectors, we view shelves and cabinets secured to the walls of car garages as unsafe and not rated for load.  Often we see home owners store items that may overload the shelves and thus create a hazardous condition.

Some home owners are correct to be concerned and should check with an expert before taking on such a simple project.  The issue to be concerned with is structural safety and the load that shelves can take.  The current home owner may be aware of these safety issues but as a home buyer moving into the home, they may not know what load the shelve and cabinets were rated for.  A worst case scenario is that new owners move in and decide to store some tires on the shelves. The shelves may sage or fail and worst, compromise the framing of the garage and the house. The new home owners call up the home inspector and complains that they were not warned of this and threatens to take legal action.

So from a home inspector’s point of view, when asked about a simple project as putting up storage space in the garage can be a legal mess.  And if the home owner insist on building such structures to the garage, I recommend they check with a structural engineer first to get proper drawing plans, building materials, and the proper skilled carpenter to build it.