Frame a specific view
Stand and sit in the room before choosing mullion locations. The best arrangement depends on where people actually gather, not only the exterior elevation.
Plan for large glass delivery
Ask how the unit reaches the opening, whether staging equipment is needed, and how landscaping is protected. Put access costs in the written estimate.
Plan for your property
A large picture window can frame a lake-facing outlook, while adjacent casements add ventilation. Plan access on sloped lots and check exterior detailing, water management, and association requirements before work begins.