Triangular windows often follow the roof line of a house and are usually located above doors or other windows, expanding the view and adding architectural interest. Though these windows are often left uncovered, there are triangular window treatment ideas that you can use to cover them to block the glare of sunlight or for additional privacy.
The easiest solution for covering triangular windows is to order custom blinds or shutters. You supply the exact measurements of your window and order cellular shades, vertical blinds or wood shutters that fit your triangular window exactly.
You can also make your own custom window cover by cutting thin plywood or even tin or copper to the shape of the window. Pierce or cut out a decorative design to let the light shine through. Quilting stencils can provide inspiration or a pattern for your design. Mount your finished piece in the window with picture framing tacks.
You can use almost any lightweight fabric to make a shirred sunburst to fit your triangular window. Gather the fabric at one corner and tack it to the window frame with small tacks or a staple gun. You can add a decorative medallion or a fabric rosette at the corner to cover the knot where the fabric is gathered.
Another alternative for triangular windows is stick-on window decals. You can easily apply these vinyl decals that come in many different designs, including faux stained glass, frosted and pebbled finishes or lacy looks. You can cut these decals to fit your window. They're easy to remove when you tire of the look or no longer need them.