Comparing the below turn of the century photo overview of Danbury yard to the second photo taken in 1919 shows the evolution of the structures and the location configuration that still existed during the mid 1950's modeling era.
Click to enlarge photos
Below, welcoming the troops home after the end of the first world war.
Copyright NHRHTA Inc. Reproduced by Permission
I am uncertain what the original purpose of the Leahy's building was, I call it the Leahy's building because Leahy's Fuels owned it during the modeling era of the layout and still does today. The top photo of this post shows that it is a single story structure and probably having originally been built as a freight house for the New York & New England RR.
In the second photo above, Danbury yard and the old NY&NE yard are now fully under control of the New Haven RR and a second story has be added to the structure. This building becoming the headquarters of the Danbury Division of the New Haven RR, this is most likely the reason the building was converted to an office type and the second story was added.
The Danbury Division was consolidated into the New Haven Division of the railroad after the second world war. Because of this division consolidation the property and buildings once belonging to the NY&NE RR across the tracks from Danbury yard where then no longer need, John Leahy purchased the entire property for his growing fuel company.
The 1940's photo below shows the building as it appeared when it was the Danbury Division office of the New Haven RR before being purchased by Leahy's Fuels.
Courtesy Bob's Photos
John Leahy was also the owner of the Danbury Fair Grounds on the west side of the city. Now under his ownership, Mr. Leahy liked to promote the annual "Great Danbury Fair" with signage on the building as seen in the 1954 photo below.
Copyright NHRNTA Inc. Reproduced by Permission
Still owned by Leahy's Fuels, below is how the building appears today.
The Model Leahy's Building.
The prototype was measured, then the model was scratch built to how it appeared in 1957 as well as could be determined. The model was built with Evergreen Styrene clapboard siding and strips of various sizes, Tichy windows and doors, Micro Mark shingles and brick siding.
No construction photos were taken, the two photos below show the almost complete model on the work bench. Steps, gutters and down spouts were added before placing on the layout.
The layout era is about September 1957, guess something will have to be done about the build date on the boxcar above!