The honest answer has two numbers, and confusing them is the most common source of frustration on a storefront project.
Time on site
Many straightforward single-bay storefronts can be completed in roughly one to three working days once materials and site conditions are ready. A full elevation on a larger building runs longer, and access conditions can add days. But the on-site portion is rarely why a project feels slow.
Time before site
This is where the calendar goes. Aluminum framing and standard clear glass are commonly a few weeks. Custom sizes, special finishes, laminated make-ups and insulating units run longer, sometimes considerably. That is fabrication — the glass is made to order for your opening, and it does not exist until it is ordered.
Nothing compresses that much. A contractor promising a two-day turnaround on custom insulating units is either not quoting custom units or not being straight with you.
What can start immediately
If the opening is broken, same-day board-up may be available depending on location, timing and site conditions. That decouples the security problem from the glass problem, which is the whole point of doing it in that order. Measurement should also happen on that first visit, so material is on order while the board is up rather than after.
What adds time
Permitting where it applies, and more in some jurisdictions than others. Design review in historic districts and covenanted developments. Discovering that the existing framing is not what anybody thought once it is opened up. And approvals — a submittal sitting on a desk for two weeks is two weeks on the date.
How to plan around it
Ask for two dates, not one: the material date and the install date. Ask what is on the critical path. If your opening date matters — a lease start, a launch, a seasonal deadline — say so at quoting stage. There are usually choices about glass make-up that trade a little performance for several weeks of lead time, and they are only useful if the conversation happens early.
