Deck Railing Balusters

Balusters or pickets are the rail components used to provide infill for deck guard rails.  IRC code prohibits guard rails from having any openings that would allow a 4" sphere to pass through.  This rule produces the need for an attractive and economical repeated system for filling in the openings between rail posts and rail top and bottom members. 

Because of the spacing requirement you will need a lot of pickets or balusters even for a short length of rail.  Balusters will certainly be the most expensive rail component for your project.  Years ago most deck builders used wood 2x2's nailed to the deck rim and top rail to meet the requirement.  Some builders even used lattice.  Thankfully this practice has mostly disappeared.