I'm not sure if the census is indexed that way. Usually I have searched for my ancestors and when I check the census I can see the address in the margins. States usually had done censuses on the 5's so there may be a 1905 census for your grandparents. Are you just interested in the location of the address? Have you Googled the address or does it no longer exist?
Dear Ms. Sangl,
Thank you for posting your request on History Hub!
We search the National Archives Catalog and located a series titled Population Schedules for the 1910 Census since they were married in 1905. Allegheny County, Pennsylvania portion of the 1910 census has been digitized and is available using the Catalog.
Since Allegheny County, PA has not been added to the Catalog yet for the 1920 and 1930 Population Schedules, digitized census records may be found for 1920 and 1930 using Ancestry. There may be a fee associated with using Ancestry but you may access the digital images at a NARA facility for free using a NARA PC.
We hope this is helpful. Best of luck with your family research!