Sounds like the upstairs outlet might be wired in series with the downstairs outlet instead of in parallel. Chances are the issue is in that downstairs outlet and it can be fixed quite easily by opening up the downstairs outlet box and checking the wiring. It's always possible it's some other issue, but that's a easy place to start.
Zoravar t1_jd8rajr wrote
Reply to comment by myrevenge_IS_urkarma in LPT: If you're buying a house still under construction, photograph everything before the sheetrock goes up. Knowing exactly where the pipes, wires, and ducts are may prove invaluable some day, and even if you never use them the next owner will appreciate it. by Needleroozer
Sounds like the upstairs outlet might be wired in series with the downstairs outlet instead of in parallel. Chances are the issue is in that downstairs outlet and it can be fixed quite easily by opening up the downstairs outlet box and checking the wiring. It's always possible it's some other issue, but that's a easy place to start.