Ambrose Hall was built in five phases from 1885 to 1912.
Each section is similar to the others and yet each section possesses its own character.
The features that are common to all the sections include round-arch windows and doorways with stone hood molds and keystones.
A stone stringcourse runs between the first and second floors on all but the first section of the building.
Finally, decorative brick corbelling runs the length of the whole building below the cornice.

The original section of the building was built from 1885 to 1887.
It is a symmetrical structure of seven bays wide with a central pavilion capped by a mansard tower.
The lower level is composed of smooth rusticated ashlar and brick on the upper floors with stone quoining on the corners.
Its mansard roof was altered in the 1960s when it original diamond-shaped shingles, gabled dormers and decorative cornice were replaced with modern windows, asphalt shingles, and a severely plain cornice.
 All those features were restored in 2013.

The second section was added to the east of the original section in 1893.
 It too is symmetrical and has a projecting central pavilion, but it is five bays wide.
It is connected to the original section by a three-bay, recessed section.
Instead of ashlar on the ground floor, it is all brick from the ground up.
Alterations and restoration to its mansard roof were like those of the original section.

The third section was added in 1901 to the west of the original building.
 Unlike the other sections it has an asymmetrical facade that consists of two symmetrical sections joined together.
One section is three bays wide and the other is 5½ bays wide and features a central pavilion.
Its mansard roof was altered later.
The tracery windows on the third floor mark the room that served as the chapel.
The central pavilion has a chapel window that is composed of two trefoil windows that are surmounted by an octofoil window.
It is enclosed in a segmental dormer.
The two hexafoil windows that flank it are set into the brick below segmental dormers.
On the west side of this section is a three-level brick porch.

The fourth section of the building was added to the east in 1908.
It reflected a simplified version of the Colonial Revival and therefore did not conform to the design of the other three sections.
The fifth section of the building remedied this problem when it was added in 1912 to the front facade of the fourth addition.
Its sole purpose was to bring the fourth section into conformity with the rest of the building.
Like the second section, it is symmetrical, five bays wide and has a projecting central pavilion.
This addition is larger than the other sections as it sits farther in the north in the rear of the building.
Ambrose Hall was built in five phases from 1885 to 1912. Each section is similar to the others and yet each section possesses its own character. The features that are common to all the sections include round-arch windows and doorways with stone hood molds and keystones. A stone stringcourse runs between the first and second floors on all but the first section of the building. Finally, decorative brick corbelling runs the length of the whole building below the cornice.
The original section of the building was built from 1885 to 1887. It is a symmetrical structure of seven bays wide with a central pavilion capped by a mansard tower. The lower level is composed of smooth rusticated ashlar and brick on the upper floors with stone quoining on the corners. Its mansard roof was altered in the 1960s when it original diamond-shaped shingles, gabled dormers and decorative cornice were replaced with modern windows, asphalt shingles, and a severely plain cornice.  All those features were restored in 2013.
The second section was added to the east of the original section in 1893.  It too is symmetrical and has a projecting central pavilion, but it is five bays wide. It is connected to the original section by a three-bay, recessed section. Instead of ashlar on the ground floor, it is all brick from the ground up. Alterations and restoration to its mansard roof were like those of the original section.
The third section was added in 1901 to the west of the original building.  Unlike the other sections it has an asymmetrical facade that consists of two symmetrical sections joined together. One section is three bays wide and the other is 5½ bays wide and features a central pavilion. Its mansard roof was altered later. The tracery windows on the third floor mark the room that served as the chapel. The central pavilion has a chapel window that is composed of two trefoil windows that are surmounted by an octofoil window. It is enclosed in a segmental dormer. The two hexafoil windows that flank it are set into the brick below segmental dormers. On the west side of this section is a three-level brick porch.
The fourth section of the building was added to the east in 1908. It reflected a simplified version of the Colonial Revival and therefore did not conform to the design of the other three sections. The fifth section of the building remedied this problem when it was added in 1912 to the front facade of the fourth addition. Its sole purpose was to bring the fourth section into conformity with the rest of the building. Like the second section, it is symmetrical, five bays wide and has a projecting central pavilion. This addition is larger than the other sections as it sits farther in the north in the rear of the building.
Ambrose Hall (Davenport, Iowa)