Asphalt shingles have three major components: asphalt, felts
and colored mineral or ceramic granules. Asphalt is a byproduct
of petroleum distillation and also occurs in natural deposits.
This dense mixture of hydrocarbons provides the waterproofing
for the shingle. The felt fibers reinforce and stabilize the asphalt,
The Barber Asphalt Co. featured their use of natural asphalt mined
from Trinadad Lake in the promotion of their shingles.
[click image for larger view] while the granule aggregates protect
the assembly from sun, wind, rain and minor foot traffic.
The roots of asphalt shingles can be found in composition roofing
that developed in the United States in the mid-19th century. In
the last quarter of the 19th century the site-layered components
of built up roofing were adapted to produce a factory assembled
product of long strips. Packaged in rolls this material, once
called "ready roofing," is now commonly known as "roll
roofing." Though naturally occurring asphalt was used
early as a waterproof coating, most built-up roofing systems relied
on the more abundant coal tar. Asphalt, however, could be processed
to be more solid than coal tar, and this solidity was necessary
to facilitate the transition from a site fabricated system to
a preassembled product. Despite the abundant and affordable asphalt
from a growing petroleum industry, the use of natural asphalt
was a point of product promotion at least as late as 1930.
The first asphalt shingles were produced in 1903 by a roofing
contractor and manufacturer of prepared asphalt roofing. Herbert
M. Reynolds of Grand Rapids, Michigan, hand cut rolls of "stone
surfaced" roll roofing into individual shingles. Early shingles
were typically rectangular or hexagonal. The colors, usually red,
green or black, were limited by the natural materials used for
the granular surface.
The popularity of this product led to the proliferation of shapes
and sizes and attachment systems, some of which were patented.
The multi-tab strip shingle was a significant development
that quickly emerged. It offered the traditional effect of a small
shingle with lower installation costs. By 1906 Bird and Son was
marketing a notched shingle that had the appearance of two shingles
Numerous factors contributed to the increased use of asphalt
shingles in the 20th century. Made of non-strategic materials
and easier to transport than wood or slate, they met the constraints
imposed during World War I. More flame resistant than wood, they
were promoted in response to a 1916 publication of the National
Board of Fire Underwriters urging the elimination of wood shingles
as a fire hazard. Additionally, asphalt shingles gained a cost
advantage over other materials. As improvements in manufacturing
processes made asphalt shingles cheaper, increased labor costs
made installation of traditional materials more expensive.
The variety of shingle shapes and sizes peaked by 1930, and
by 1935 all major manufacturers were offering a 12 by 36 inch
multiple tab shingle that is the standard today. At the same
time the introduction of ceramic granules allowed a wider
range of color choices that were often mixed to produce a blended
shingle. The most significant recent change in the product itself
is the replacement of organic felts with fiberglass mats
resulting in a stronger, more durable shingle.