Researching your District of Columbia Home

1. Identify Square and Lot
To find the current square (city block) and lot (parcel of land), consult the current Assessment Directory kept at the reference desk. The square and lot may also be found by searching the D.C. Office of Tax and Revenue's Real Property Tax Database.

Consulting historic real estate, or "plat" maps will help determine if a lot had an earlier lot number before being subdivided. The atlases we have include those published by Hopkins (1877-1890s) and Baist (1903-67).  Some Baist atlases have been digitized by the Library of Congress.

2. Find Original Permit to Build
Washingtoniana has microfilm of building permits from the National Archives, all permits issued from 1877-1949.  The most important permit to find is the "Permit to Build," and the best way to find that permit is to search the Building Permits Database (only available onsite).  The database includes most of the information from the original permit, including date of construction, architect, builder, owner, materials, dimensions, cost and use of the building.

Permits issued after 1949 are available at the D.C. Archives.

3. Find other Permits
There may be other permits associated with a property in addition to the Permit to Build, such as permits to build an addition, to add stories, to add a facade, etc. These permits must be accessed using the microfilm indexes:

By Square Number 1877-1928
By Subdivision 1877-1908 (for property in Washington County - above Boundary St./Florida Ave., east of Anacostia River; consult plat maps for subdivision names)
By Street Address 1928-1958

4. Research Ownership
Washington Board of Realtors Transaction Fiche is a good place to start to identify changes in ownership that took place between the 1920s and the 1980s.  The cards are on microfiche, and are organized by square and lot. To find owners not covered by the transaction fiche, consult the Assessment Directories, 1886-present on microfilm.

5. Research Residency: City Directories
Starting in 1914, city directories include a street directory. Using this "reverse" directory, you can discover who lived at a particular address. Then, if you look up the individual in the name directory, you can often find their occupation and place of employment. Our city directory collection dates from 1822.

6. Research Families in the Census
Searching for the individuals associated with a property in the Census can yield a great deal of detail about the family such as other family members, race, place of birth, and occupation. Start with the HeritageQuest database, through which the following census years may be searched by name: 1790-1820; 1860-80; 1900-30. All census years between 1790 and 1930 may be browsed (except the 1890 census that was burned). Washingtoniana also has print indexes (1800-70, 1910), and soundex indexes (1880, 1900, and 1920) for searching by name.  
  
Searching by general location is possible for the following years: 1880, 1900, 1910, 1920, using enumeration district maps.

7. Conduct Newspaper Research
Additional information about a property and the people associated with it can be found by doing newspaper research. A great place to start is The Washington Post Historic (full-text searching 1877 to 1990, including articles and ads). 

TIP: Search names and addresses in parentheses to narrow results.

Washingtoniana has many other historic D.C. newspapers on microfilm dating back to 1800. These are generally not indexed in such a way that is useful for researching house history; however the vertical file collection is worth consulting. These newspaper clipping files cover a variety of subjects, such as houses, streets, neighborhoods, institutions, and individuals by name.

8. Visit Other Local Institutions for Further Research
D.C. Archives
D.C. Historic Preservation Office
D.C. Recorder of Deeds
Historical Society of Washington
Library of Congress
National Archives