Historic District Windows

Preserving the Charm of Boise’s Historic Districts

The windows within historic districts are as varied as the houses themselves. Each architectural style’s unique windows are integral to interpreting the style. Altering the windows can potentially change the structure’s status from contributing to noncontributing to the historic district. The window type (slider, double hung, single hung, etc.), the material used (wood, vinyl, aluminum, etc.), and the window depth within the wall plane all affect the overall building design.

Whether ornate or plain, windows are an integral part of a building’s style, and express its history and architectural style. Although it is easy to see the need to preserve the high-style windows of a Queen Anne mansion, the humbler windows of a small cottage are as important since they may be the building’s only stylistic feature. On a simple building, altering the windows’ shape or configuration could easily change the structure’s entire appearance and historic integrity.

Vinyl windows

Vinyl windows are not permitted within Boise’s Historic Districts. When replacing existing vinyl windows on a property, an approved material must be installed. If you have questions, please contact Historic Preservation staff at (208) 608-7100.

Download the Historic District Windows brochure for more information and illustrations of different window types.

Historic District Windows (PDF)

The Secretary of the Interior

The U.S. Department of Interior has written a set of Historic Preservation recommendations titled Standards for the Treatment of Historic Properties. These guidelines are widely used by the nationwide preservation community. This resource was used in developing the City of Boise Design Guidelines for Residential Historic District document. In this publication, the Secretary of the Interior recommends against “changing the historic appearance of windows through the use of inappropriate designs, materials, finishes, or colors which noticeably change the sash, depth of reveal, and muntin configuration; the reflectivity and color of the glazing; or the appearance of the frame.” (pg. 81).

Although a vinyl window with a large sill depth and compatible framing may meet this recommendation, the figures below illustrate the results of using an incompatible material and design when replacing a historic window.

Historic Window Modifications

The Secretary of the Interior recommends “identifying, retaining and preserving windows-and their functional and decorative features-that are important in defining the overall historic character of the building. Such features can include frames, sash, muntins, glazing, sills, heads, hoodmolds, paneled or decorated jambs and moldings and interior and exterior shutters and blinds.”

When making decisions regarding renovations in a historic district, fi rst identify these important window features. Consider making small improvements such as removing paint that has sealed the window closed, and weatherproofing by recaulking or installing weatherstripping or storm windows. If elements of the window’s structure have rotted, consolidation or in kind replacement of those elements can be an effective way to save an otherwise viable window while retaining the window’s character defining elements.

The Secretary of the Interior states that when an entire window is too deteriorated to be saved, the replacement of the window is acceptable. However, it is important that the new window is compatible with the structure and the other windows. For instance, if the historic windows are long, double hung windows, replacing them with short, wide horizontal sliders is inappropriate. Likewise, if a large, multi-paned window has always been on the front elevation of a house, replacing it with two single-hung windows is inappropriate. Replacement windows should be congruous, or compatible with the shape, placement and material of the windows historically on the house.