Trellis/Arbor Details There's nothing magical about the heights or widths of the trellis or the arbors. Alter the trellis dimensions to fit whatever it is you want to screen or size the arbors to border your own sidewalks. But if you build a trellis or an arbor that's wider than 6 ft. (our width), add posts in the middle. If you want to walk under the arbor, be sure to make the 2x8 lintel high enough after allowing for ground coverings (80 in. minimum is a good rule of thumb).
