First National Bank Building / 100 Federal Street
Boston knows this 1970 job by a much less formal name: the 'Pregnant Building.'

The First National Bank Building at 100 Federal Street in Boston, Massachusetts. Also known as the "Pregnant Building" due to its. Photographed in 2014; a current view, not a construction-period photograph.
Current view · 2014 · Photo: Tim Pierce · CC BY-SA 3.0 · Source
Why this project matters
- Project identity
- Verified
- Kelly connection
- Family source
- Masonry scope
- Probable
Rita’s list

Transcription: First Bank of Boston — 1970
Recorded by Rita Bartscherer · Bartscherer family record
KM-076
1 of two
“First Bank of Boston — 1970”
100 Federal Street was under construction from 1968 to 1971, exactly spanning Joseph's 1970 entry.
Boston nicknamed 100 Federal Street the 'Pregnant Building' because several lower floors swell outward. The bulge gave the bank more office space while preserving wider views along the street—an odd-looking compromise that made the 1971 tower unforgettable.
What Kelly did here
Family source
Probable
Likely: most plausibly interior CMU/block at the core, stairs, shafts, service rooms, fire separations and support spaces. Do not attribute the tower's visible dark red granite cladding to Kelly without a stone/masonry trade record; the granite exterior may have been a separate specialty package.
This scope is recorded as probable, not documented. It is a disciplined reading of the building and the trade practice of the period, not a contract-level record of Kelly’s work.
The construction team
- 01Architect
Campbell, Aldrich & Nulty
What happened to it
Still standing
Sources
4 citedOpen →
- 01
- 02boston.com
then and now building bostons skyline
- 03commons.wikimedia.org
File:100 Federal Street Boston Massachusetts.jpg
- 04bxp.com
100 federal street
- Tim Pierce · CC BY-SA 3.0 · Wikimedia Commons · 2014-03-06
The First National Bank Building at 100 Federal Street in Boston, Massachusetts. Also known as the "Pregnant Building" due to its. Photographed in 2014; a current view, not a construction-period photograph.
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