Dorothy was fearful of wild animals in the forest on her way to the Emerald City but you don't need to be fearful of designing window treatments with arches and scallops and bows. Sometimes the curves are forced on us because of the architecture in the room, such as a bow window or a window with an arched top. Other times we add curves as embellishments or to soften the hard geometric lines in the rest of the room or to add height to the treatment or to highlight the hem shape.
From a mathematical standpoint, a scallop is just part of a circle. Flip it upside down and it is an arch. Turn it on its side and you have a bow.
The shape of the scallop is based on its width and height. As a designer, you know how wide the window is (scallop width) and you know what you want the long point and short point of your treatment to be(scallop height). From there, it is a matter of geometry to draw the scallop to those exact specifications. Do you remember using a compass in geometry class? In just three easy steps, you have a perfect scallop.
But enough of the math lesson...let's take a look at how they are used in window treatments! The first four examples show using scallops and arches to make a curved hem shape. The upper left hand picture is a pleated valance with an arched shape on each box. The upper right hand picture is an operable roman shade with a scalloped hem. The middle picture is a pleated valance with arches and scallops of different widths on the boxes. The bottom picture is an awning valance with a serpentine shaped hem. A serpentine shaped hem is made by alternating arches and scallops of the same dimension.
The next group of pictures has window treatments with arched tops. The top picture is a box pleated valance with an arched top and an arched hem shape. The middle picture is a pair of mirror image Moreland valances. The windows themselves were not arched. The arched tops were added to echo the arched window over the fireplace. The bottom picture is a stationary relaxed roman with two swoops. The protruding molding on the adjacent cabinets prevented the valance from being mounted above the window molding. The arched top adds height to the treatment and fills in some of the wall space above the window.
The final example is of a pleated valance for a bow window. This bow window was 12 feet across. Now that is one big scallop width! Clearly I needed something bigger than my school compass to draw the bow shape. I used a string with one end tied to a thumb tack and the other end tied to a pencil. The first picture shows me out in my driveway marking the bow shape on some plywood. The second picture shows the finished valance installed on the bow window.
If my talk of scallop widths and using a compass reminds you of Sheldon at his white board, fear not! You come up with the design and I'll take care of the geometry. If you want to add some scallops or arches or bows to your next project, email me at firstname.lastname@example.org and we'll walk through that scary forest together.