The cost of a bay window installation typically runs from $400 to $8,000. Low estimates range from $400 to $3,000, including installation, according to ImproveNet by CraftJack. Moderate estimates run from $800 to $8,000, says CostHelper.com.
Several variables affect the cost of a bay window installation. The choice of material is a factor. Vinyl is less costly and lasts longer than wood. Fiberglass costs more than vinyl or wood but offers insulation, versatility and flexibility, states The Replacement Windows Advisor.
Another factor affecting the cost of a bay window is whether it’s a replacement window or a new installation. Often, adding a bay window requires structural changes in the home if it’s replacing a flat window pane. In some areas, a bay window is considered a remodel and must have a local building permit.
Other factors are the thickness, rating, tint and number of glass panes, the quality and price of the hardware finishes, the size of the window, the complexity of the installation and labor costs. Generally, an experienced professional is required due to the structural changes and complexity of the project, says CostHelper.com.