At Archadeck of Charlotte we get asked about lattice or skirting options for under a deck all of the time. The traditional way to enclose under a deck is wood lattice. This can be done inexpensively by tacking up some prefabricated thin lumber strips. A better way is to use 3/4″ pressure-treated wood lattice and picture frame it with wood trim and create an access door to be able to store things under the deck.
Other options for skirting under a deck include vinyl lattice with composite trim. You can also take deck boards and run them horizontally for a different look. With the same thought in mind, you could run the deck boards vertically.
You are not limited to lattice when looking for options to skirt your deck. For great photos of decks, go to http://www.Charlotte.Archadeck.com