Originally Posted by bomfunk
Oh of course, it never occurred to us that he could tools that he's used his entire life, having spent most of his life in the construction industry! That's brilliant!
...he'd really like to use a computer for this one.
In that case, as previously stated, sketch up. It's free, and readily accessible to anyone with interwebs. Aside from that, just about anything you can think of for 'drawing' on the computer will do just fine, if you must stick with free that is.
Generally, someone who's been a career drafter/architect/eng./whatever, even if they never used cad, would not need to ask such a question.
Anyway, depends what his reasons are for wanting to do this. If he's just wanting to mess around w/ something that's fine. But tbqh, if he's wanting to start actually drafting w/ cad, he needs to just buck up and buy a copy of autocad. Screwing around w/ free this - free that will just be a waste of time & effort if that's the case. I've seen a lot of old school manual guys try to switch over, and trust me, trying to learn on an app. that's totally irrelevant to what's actually used in the workforce will only compound any difficulties he might have & be a total waste of time.