PORTLAND ARCHITECTURE · A FIELD GUIDE
Second Empire
1855–1890
The Mansard roof. Paris on a Portland street.
Second Empire houses take their name from France under Napoleon III, when the mansard roof became the signature of fashionable Paris. The American version is often an Italianate house with a different hat: the same brackets and tall windows, topped with a steep, double-pitched roof that turns the top floor into usable living space. If the upper story looks like a wall of roofing pierced by dormers, you are probably looking at Second Empire.
How to recognize it
Mansard roof
A steep lower slope, nearly vertical, with a low-pitched or flat deck above it.
Dormer windows
Dormers set into the steep slope, often with arched, pedimented, or curved tops.
Decorative roofing
Patterned slate or shingles in bands of shapes or colors on the lower roof slope.
Bracketed cornice
Brackets under the eaves at the base of the mansard, much like Italianate houses.
Towers and cresting
Larger examples may have a central or corner tower and iron cresting along the roof ridge.
What Nathan looks at on a tour
Nathan’s 23-year career in structural engineering shapes what he notices on a walk-through. These notes are general, informational guidance for houses of this era and construction type, not a diagnosis of any particular home. Use them as questions for a licensed home inspector and the right specialists.
The upper roof deck
The shallow top of a mansard roof is easy to overlook from the street. Ask the roofer how it drains, what the membrane or covering is, and how old it is.
Dormer flashing
Each dormer in a steep slope is a set of flashing details. Ask about staining on upper-floor ceilings and walls, and what the roofer sees at dormer cheeks and sills.
Roof framing at the break
The transition between the steep and shallow slopes carries real load. Ask the inspector to look for sagging or spreading, and a structural engineer if anything looks out of line.
Top-floor comfort
The mansard story often has little insulation behind its sloped walls. Ask what is in those cavities and how the space heats and cools.
Original systems
As with other houses of this era, ask a licensed electrician about any knob-and-tube wiring and have the side sewer scoped.
Living with it
Roofing is the main ongoing cost of a Second Empire house, because the steep lower slopes and dormers need skilled installers and patterned slate or shingle replacement takes time to match. Insulating and ventilating the mansard story is worth planning carefully so that moisture does not get trapped in the sloped walls. Interior updates usually respect the tall ceilings and window heights of the lower floors.
Questions, answered plainly
Is the top floor of a mansard house real living space?
Often, yes. The steep roof acts almost like a wall, so rooms under it can be full height for most of their area. Check ceiling heights, egress windows, and permit history if the space is being counted as bedrooms.
Why are mansard roofs expensive to maintain?
The steep lower slope and multiple dormers take specialized labor, and decorative roofing materials can be costly to match. Getting a roofer’s assessment during the inspection period helps set expectations.
Touring a Second Empire house? Ask Nathan what to look for.
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