Most also offer 90-degree box bays. Each bay type comes in hundreds of standard and custom sizes to fit any opening. Most windows are made of wood or vinyl. Exterior finish options include primed wood, extruded vinyl and wood clad in low-maintenance aluminum or vinyl. Primed-wood windows are economical, but they must be painted and periodically scraped and repainted to prevent rot.
Most bays come with insulated glazing-two panes separated by an air space.
If you want higher energy efficiency, order the window with argon gas between the panes, or opt for low-e glazing that admits solar heat in winter and reflects it in summer. What you'll pay. That's why it's important to shop around for the window that best suits your home, budget and time schedule. A brass bar running above the bay unit supports a glass shelf. Whichever bay window you're considering, review the following five questions before you buy.