Bay and Bow Windows

Bay and bow windows push the glass out past the wall, and the running record carlsbad new windows pretty little wine moms holds shows that most of the trouble begins with support, not glass. A new window of this kind in Carlsbad, CA changes the roofline and the floor plan, so the structure around it matters more than the unit.

The difference between a bay and a bow

A bay window usually has three panels, a flat center and two angled sides, set at thirty or forty five degrees. A bow window uses four or five narrower panels in a gentle curve. A bay looks sharper and more architectural, while a bow looks softer and gives a rounder seat.

Seat boards and support

The seat board at the bottom is the weak point. It carries the weight of the whole unit, so it is supported with cable from above or with brackets from below, or by framing under the seat. A heavy window with insulated glass and a double pane can sag over time if the support was skipped.

The roof above

Water has to be shed from the top of the window, so a small roof or a flashed header is built over it. In a stucco wall, the edge of that roof is sealed and flashed into the wall with careful laps. Leaks at that corner are among the most common problems on older projecting windows.

Insulation underneath

The seat board and the underside of the window are exposed to outside air, so they are insulated like a small floor. Without insulation, the cold bottom of a bay causes condensation on the glass. In Carlsbad the damp, mild winter nights make that visible on the first cool morning, as a band of fog on the lower panes.

Fitting into an existing wall

Replacing a flat window with a bay means opening the wall wider, adding a header and sometimes changing the exterior finish. Neighborhoods near Rancho Santa Fe and Carlsbad Village have different rules about projections. The existing wall framing is checked before any new design is chosen. If the wall carries a roof load above the opening, a larger header goes in first, and the cost in time and framing is weighed against simply choosing a flat picture window with an operable window beside it.