Attached vs Detached vs Semi-detached Houses


Since moving from Center City Philadelphia to a suburban area outside the city it has been fascinating to see the dynamics building structure types can play into the quality of different neighborhoods. I don’t mean quality in a good or bad way, but in a unquantifiable sense or feeling the neighborhoods evoke.

I got my degree in landscape architecture and went on to practice for seven years in the industry. Part of practice and education heavily focused on urban planning and building communities. I’ve always been more drawn to urban areas because of that. However, I’ve also always loved moving around and experiencing something different. Since moving to Philadelphia in 2014 I’ve lived in several townhomes, and and apartment unit but last year my boyfriend and I bought a Twin!

When searching for a home the type of building structure may be really important to you. I’ve broken down the most common building structure types here to help explain the differences.

Homes that are semi-detached share one common wall. The houses are situated on the edge of the property line so the property boundary is in the middle of the partition wall. You might see these being called “twins”. Developers who constructed these homes often used the same layout for both sides but mirrored.

Twin homes can easily be confused for duplexes, which is a single structure with two units on the same property line.

Detached homes are single family single structure homes with no other units touching the building. These are most common is suburban and rural neighborhoods. Detached homes often have yards and driveways and are considered to be more private.

Attached homes are more commonly found in urban areas and city centers. Two sides of the home share a common wall with neighboring buildings.

In the example above the townhomes on the left and right are known as end row units. End rows are on the edge of a block and have sidewalks on the front and side of the home.

Units of a building are all within the same building but are separated from neighboring properties vertically or horizontally. In the example above, if each floor is a separate unit this building has four units. In this case, one may refer to this as a quadplex. (duplex=2 units, triplex=3 units, quadplex=4 units)

Access to the building is typically through a shared front door but inside each unit has a private entry. Condos are also considered units because condo owners might own the second floor unit of a single complex. These often come with a condo association in which common area maintenance is shared among all owners of the building. Owners do not own the land that the unit sits on.

Final Thoughts

When making a decision on what type of structure you may want to live in or purchase there are many factors to consider. Each type of building offers advantages and disadvantages that only you can judge what your preference is. My entire adult life I’ve moved from townhomes to units and now I’m living in a semi-detached twin. I don’t mind having close neighbors but maybe at some point I would like the privacy of having a detached house.

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Hi! I’m Kristy Pedersen. I’m renovating houses in Philadelphia and sharing the process one step at a time.



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