To learn more about these polygons and what they represent one may visit Antero Pietila's site for a short synopsis.. The original 1937 Baltimore Residential Security may be downloaded from the Sheridan library at this link.
The legend for the 1937 map of which I created these polygons is below.
Here is an image of the original map.
The Explanation of the map provided by the Homeowners Loan Corporation, Division of Research and Statistics, is as follows:
Home Owner's Loan Corporation used the George Cram 1935 " Street Map of Baltimore Area" as a base map to overprint the Residential Security Information. At the time of publication, the following information was prepared by the staff of the Home Owners’ Loan Corporation as an explanation for this map: “Prepared by: Division of Research & Statistics With cooperation of the Appraisal Department May 29, 1937. EXPLANATION Baltimore, Maryland The purpose of the Residential Security Map is to graphically reflect the trend of desirability in neighborhoods from a residential view-pint. Four classifications are used as indicated by the legend, namely: First, Second, Third and Fourth grades. The codes letters and colors are A, B, C, and D, and Green, Blue, Yellow and Red respectively. In establishing the grade of an area, such factors as these are considered: intensity of the sale and rental demand; percentage of home ownership; age and type of building; economic stability of the area; social status of the population; sufficiency of public utilities, accessibility of schools, churches, and business centers; transportation methods; topography of the area; and the restrictions set up to protect the neighborhoods. The price level of homes is not the guiding factor. The First grade of A areas are “hot spots”; they are not fully built up. In nearly all instances they are the new well planned sections of the city, and almost synonymous with the area where good mortgage lenders with available funds are willing to make their maximum loans to be amortized over 10-15 year period – perhaps up to 75-80% of the appraisal. They are homogeneous; in demand as residential locations in “good times” or “bad”; hence on the upgrade. The Second grade or B areas, as a rule, are completely developed. They are like a 1935 automobile – still good, but not what the people are buying today who can afford a new one. They are neighborhoods where good mortgage lenders will have a tendency to hold loan commitments 10-15% under the limit. The Third grade or C areas are characterized by age, obsolescence, and change of style; expiring restrictions or lack of them; infiltration of a lower grade population; the presence of influences with increase sales resistance such as inadequate transportation, insufficient utilities, perhaps heavy tax burdens, poor maintenance of homes etc. “Jerry” built area are included, as well as neighborhoods lacking homogeneity. Generally, these have reached the transition period. Good mortgage lenders are more conservative in the Third grade or C areas and hold loan commitments under the lending ration for the A and B areas. The fourth grade or D area represent those neighborhoods in which the things that are now taking place in the C neighborhoods, have already happened. They are characterized by detrimental influences in a pronounced degree, undesirable population of an infiltration of it. Low percentage of home ownership, very poor maintenance and often vandalism prevail. Unstable incomes of the people and difficult collections are usually prevalent. The areas are broader than the co-called slum districts. Some mortgage lenders may refuse to make loans in these neighborhoods and others will lend only on a conservative basis. These maps and description have been carefully checked with competent local real estate brokers and mortgage lenders, and we believe they represent a fair and composite opinion of the best qualified local people. In using them we do not mean to imply that good mortgages do not exist or cannot be made in the Third and Fourth grade areas, but we do think they should be made as serviced on a different basis than in the First and Second grade areas. The following local persons collaborated with the field agent in the preparation of this map and the area descriptions: Mr. J.J. Requardt, Real Estate Broker, Robert M. Morfort, Real Estate Broker, Mr. Harry B. Wolfe, Real Estate Broker, Mr. A.D. Clemens, Real Estate Broker, Mr. Joseph M. Hisley, Real Estate Broker, Smith Real Estate Company, Real Estate Broker, Mr. George P. Klein, Real Estate Broker, Mr. Lemmon, Chief Evaluator – F.H.A, Mr. Ivan McDougal, Professor Economics and Sociology – Goucher College, Piper and Hill, Real Estate Brokers, Mr. H.W. Irr, Secretary, Pennsylvania Avenue F.S.L.A., Mr. F.W. Brochman, Cashier, West Baltimore Building Association, Dr. Conrad, Home Owners’ Loan Corporation – Towson, Mr. Francis L/ Smoot, State Appraiser, HOLC, Mr. L. Krover, Assistant State Appraiser, HOLC, and Mr. Wm. Martein, R.E. Operator, Baltimore. NOTE: A street index will be found on back of map. The area descriptions were arranged alphabetically according to the code letter and numerically.”
Blogger's comment: The blog owner never appreciated all the hoops she had to jump through because in 1989 when she attempted to purchase her home in a neighborhood that was still red-lined by commercial banks and thus she could not get a traditional mortgage. The blog author still remembers clear-as-day when her own bank manager at Maryland National Bank strongly suggested she "instead buy a house in Glen Burnie". Yuck!
