how do u build when u are in Command chair as a commander?

[scyther]

i know there is a way to do this, have seen this many times in games.
could anybody be kind to tell me plza?

[Ska]

its only on certain maps, ive only seen it done on custom maps i dunno about the originals. when your in comm just center over a structure and hold use key to build it yourself

[KiLLaBaNK]

Building while you are in the Comm-Chair is impossible unless you are on a map where the ceiling is higher than the commander veiw. (eg, missilecommand) The ceiling is way above with the aliens. There for, the commander view can 'Use' on objects.

Don't Cheator! laf.