Android 2019 - Zip 15905, 15905 zip code (westmont, pennsylvania) profile - homes, 72% of the 15905 zip code residents lived in the same house 5 years ago. out of people who lived in different houses, 63% lived in this county. out of people who lived in different counties, 50% lived in pennsylvania. 91% of the 15905 zip code residents lived in the same house 1 year ago.. Zip code 15905 map, housing stats, more for johnstown, pa, Zip code 15905 is located in southwest pennsylvania and covers a slightly less than average land area compared to other zip codes in the united states. it also has a slightly less than average population density.. Zip code 15905, johnstown, pennsylvania | zipcode.org, Zip code 15905 easy url: 'zipcode/15905' for johnstown zip code..