Do I Need Planning Permission for a Pitched Roof Over a Bay Window?

Bay Window and Site

• Building permits are usually required for such property modifications as house additions, house alterations that impact the structure, changes in setbacks of buildings from property lines, and in some cases, changes in architectural form. Building officials generally need layout information, structural details and appearance facts to determine your addition's status as requiring or not requiring a permit. Bay windows are generally among the extensions or renovations that trigger the permitting process. The roof line of the bay window, or any addition, is one of the elements that involves structural design, aesthetic character and setback.

Characteristics of Bay Windows

• Bay windows project from the house facade in square -- box bay -- or angled form. The construction for bay windows is complex, needing attention to structural support and moisture issues. A bay may be braced from below or supported by cables from above. When the bay can't be tucked underneath the eave of the main house, or when it's located on a gable end, it needs to be protected by a small roof or a roof skirt.

Building Permit Requirements

• Building permits usually require preparation of a plan, showing the planned construction, dimensions, structural details and, in the case of a development that extends outside the footprint of the house, a site plan that shows the relationship of the proposed structure to the property line. A bay window has to comply with setback requirements -- prescribed distances from property lines -- which could be affected by roof overhangs as well as the window.

Architectural Considerations

• Bay windows are a significant architectural feature for a house facade, especially for the front. If the house has a noteworthy architectural feature or is located in a neighborhood with established historic or aesthetic guidelines, building officials will review the appearance of the window, including the roof design, for compatibility with established architectural and visual character protocol. Roof pitch, orientation, complexity and materials are key considerations in the review of your proposed bay window feature.