How to Find Legal Lot Size to Build

[Marc Possoff]

Hi I’m currently completely renovating a house in the Grays Ferry section of Philadelphia which is going good. 

I also own a vacant lot not too far from the house which I inherited. It’s supposed to be 14x51 / 714 sq ft. The lot sits between 2 row houses. I went to measure the lot this morning and the measurements aren’t coming up. My measurements from the end of the 2 houses is less than 14’. 

I then did some Google-ing and found a site https://atlas.phila.gov/ I put the address of the my in and it’s saying perimeter 126 ft, Area 681 sq ft. 

When I input the address for the 2 houses where the lot sits between in https://atlas.phila.gov/ 

House on right: Perimeter 128ft Area 731

House on left: Perimeter 127ft Area 692

When I did some other research, it’s saying that all the lots on the street are 714 sq ft, 14x51.

I measured a bunch of houses that were attached together and they are pretty the same size. But doesn’t seem like my lot would be the same size.

Am I missing something? And how do I find the legal size of the lot? Thanks!

[Troy Sheets]

Originally posted by @Marc Possoff:

@Troy Sheets what would be the approximate per sq foot to build on a 14x51 lot with medium to high finishes and a finished basement? This house that I’m currently renovating is going to be a rental. I paid peanuts for it many years ago. 

Infill lots you can build 75% lot coverage, corners get you 80%, so you need to know that to determine max square footage you can build. If it's a corner you're also going to spend more on windows and siding. From the pics above you've got neighbors both sides so you're infill and 75% lot coverage. Assuming you can build 3 stories with no setback on the third floor (if you're a corner property, if either adjacent house is 3 full stories, or if either lot alongside yours is vacant) you can go 3 stories. If not, you can still build a 3rd story but you have to setback the 3rd story 8' from the front. So, assuming you can go 3 full stories (plus a basement) at 75% lot coverage, you're looking at 14' x 51' x .75 = 535.5 ft per floor x 4 floors for a total of 2142 sq ft. Let's say you'll be at $120/ft to build so you're at ~$257k in build costs not counting another ~$10k in architecture and engineering. Without plans to get quotes from subs and finishes picked out or allowances for finishes given, it's impossible to accurately predict the build cost, but this should get you close enough to decide if you want to get an architect and builder involved and start down that road. For everyone else reading this, larger houses can cost less per sq ft to build and smaller can cost more, this is literally a ball park guess knowing nothing about the structure, finishes, etc. 

Oh, if you're building this for your personal residence then I'd add another $20k for the "while you're at its" or "scope creep". While you're at it you may as well upgrade the cabinets, add a sound system throughout the house, use the fancy $10/ft tile, etc. It happens every time! 

Hope this helps.