It's worth the money...

Do you know why silk drapes look so good?  Not only do they have a natural sheen, but that full soft hang and lush curves is what really makes the treatment.  But that hang and look is not entirely the silk itself.  Properly made silk treatments have a third layer between the face fabric and the lining.  This piece is called interlining.

Interlining is a felt like fabric sometimes referred to as "bump" although most people talking about bump are interested in a thicker fabric than what is used here in the states.  The interlining not only adds that nice roundness to the pleats, but also helps protect the silk from fading and dry-rotting from the light and heat of the sun.

Because interlining is not only for looks if the additional expense is greater than you can squeeze into your budget  I suggest that you consider using a faux (fake) silk instead.  These pieces are normally made of polyester or viscose and can look nearly the same without having quite as much vulnerability as silk has.  The other option is to use a lining with an attached interlining (like a flocking).  I have heard good things about one from my friends at Fabricut (www.fabricut.com) but haven't personally used it yet.