When you need one layer of fabric to open and close with a cord and another layer to remain stationary, combo traverse curtain rods are an excellent choice. Both rods will install on the same set of brackets which will really cut down your installation time. Both regular size curtain rods and wide face curtain rods are available with combo rods for the non-operable portion of your treatment.
Pay close attention to the style of combo curtain rod you pick out for your drapery hardware treatment. Some rods come with the stationary layer in the back and some are made with the stationary layer in the front. A fixed front section is typically used for a valance. If your valance has a large rod pocket three inches or greater, then a combo rod with a wide face curtain rod is probably your best option. For one or two inch pockets, a standard size curtain rod will work fine.
Combo traverse curtain rods with a stationary back layer are most often used with non-operable sheers. Or, with sheers installed with rings. You can use the small rod pocket at the top of the sheers with the standard rear curtain rod section of your combo rod.