Brief History of Billboards
Prior to 1900 outdoor signs and billboard of every size and description were common in most urban areas of North America. Soon after the turn of the century, the advertising industry moved toward standardizing the size of outdoor billboards. The advertising industry finally settled on three standard sizes with 10-feet high by 22-feet wide emerging as the most commonly used.
The growing popularity of automobiles combined with the Federal Highway Act of 1921 resulted in more highways and more opportunities for roadside advertising.
To simplify installation, preprinted billboard images were often smaller than the full 22 x 10-foot frame. This resulted in a wide white border which is not desirable in a model as it appears that an oversized frame is being used.
The support structure of billboards typically consisted of a flat plywood or a galvanized sheet metal surface mounted on a series of 12x12 posts sunk into the ground. Self supporting structures usually had a network of angled braces supporting the uprights. A catwalk across the bottom of the frame gave working access for the crew servicing the sign.
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Steel I-beams or retired telephone poles were also used, especially if the sign was excessively tall. Changing the image on billboards mounted directly on buildings could be a challenge.
The surrounding edge of the billboard structures in up-scale neighborhoods often included fancy molded pieces, finials and decorative corners all designed to provide an attractive picture-frame image to the product being advertised. Billboards were typically lighted with three to six flood lights. Top mounted fixtures were preferred since lights at lower levels were subject to vandalism.
Fancy white frames tend to look toy-like in a modeling scene. For authenticity it is usually safer to model the typical rather than the unusual.
The support structure beneath the billboard was often hidden with horizontal slats or lath work. The entire support structure was painted a common color – usually medium to dark green. During World War II advertisers received tax credits for promoting the sale of War Savings Bond in their ads.
Although unplanned, billboards advertising modern items often appeared in contrast to impoverished or rundown neighborhoods.
Preprinted 10x22 outdoor billboard advertising was the standard until the late 1950s when full-bleed or frameless studio-painted panels, 3D effects and cutout images that extended beyond the supporting framework gained popularity.
The steady disappearance of outdoor billboards began in 1965 with the implementation of the Highway Beautification Act. Tobacco advertising was banned on radio in 1972 leaving outdoor advertising as one of its most popular venues until 1999, when tobacco advertising was banned from billboards as well.