The initial cost of drywall-constructed walls is significantly less than commercial glass walls. Glass may be a better choice in spite of the higher upfront cost if the design needs of the office space are better served, making the space more valuable. Also, perhaps of greater importance, you can use glass in modular flex-space wall systems. Over time, modular, flex-space wall systems may provide more utility at less cost and with less environmental impact.
Drywall in Offices
Drywall is the standard interior wall construction method for residential dwellings. It's inexpensive and easy to repair. You permanently apply drywall to framing members with purpose-specific fasteners: either nails or screws. Once constructed, drywall over wood wall framing is not intended to be moved. Moving a drywall-constructed wall means destroying it and rebuilding a new wall. It's a messy, time-consuming operation, and the old wall will likely wind up in the landfill as it is not practical to recycle.
Commercial Office Walls
Commercial office buildings are often built with trusses, creating an open-shell interior for tenants or owners to design as they please; there are no interior load-bearing walls. This is a fundamental difference from residential construction. While residential construction sometimes uses trusses, drywall-constructed interior walls are often load bearing members. Glass walls are not load bearing construction members. Drywall constructed walls also provide a semi-hollow space to use like a conduit for wiring and plumbing. Glass walls don't provide a conduit space for wiring; office spaces generally have space between a false ceiling and the structural floor/ceiling above it. This space is used for wiring, plumbing and ductwork with shielded electrical receptacles often being placed in the floor and lights being motion activated.
The nature of "shell spaces" allows for flex-space. Flex-space conceptualizes office space in modules with walls, offices, cubicles, utility rooms and meeting rooms designed to be reorganized with relative ease. The purpose of flex-space is to accommodate a growing or changing company or for a building owner to accommodate multiple growing and changing tenants. Drywall constructed walls are poorly suited to flex-space. Each rearrangement would require the demolition and rebuilding of new walls. You can amortize the higher upfront cost of modular wall systems, such as glass walls in extruded aluminum racks, over the cost of each rearrangement. The rearrangement is less expensive and time consuming than drywall.
Design Needs and Hybrid Walls
Office space can benefit from see-through walls. Co-workers can know when an office is occupied. Transparency can have both benefits and drawbacks, however. A conference room, for example, may benefit from audio privacy where visual privacy is less important. An office worker, however, may find an entire glass wall distracting due to other office activity. Hybrids are sometimes a good solution. A portion of the wall is opaque drywall and a portion — sometimes a small portion — is glass in an aluminum frame. This provides co-worker interaction and some privacy while mitigating distractions.