Updating from two prone outlets to three prone outlets

[Benjamin Beyer]

Hi BP Nation,

I am currently house hacking a two-family home in Milwaukee, WI. I've been making updates throughout the property as needed and one of the things I noticed is that all the outlets upstairs are "three prone outlets" (Like the ones you'd see in a modern house), while all the outlets down stairs are two prone outlets. I am wondering if anyone has see this before and knows why that would be. 

Also, do anyone know how I would update the downstairs outlets? Is this a project I could handle? I've replaced outlets before but do I need to run wire to do this update?

Thanks!

[Justin Tahilramani]

@Benjamin Beyer - there is a safe (code compliant) and inexpensive way to address this by adding one GFCI outlet to each run of outlets and converting the remaining outlets from two to three prong. Talk with a licensed electrician.