iopsis iefined. A historical sketch ent of asphalt roofings and ry of new crude Petroleums ced from them upon the nent. es which should be conf asphalts for the manufacigs and shingles and for use ilt-up roofing are discussed. iaracteristics of typical roll rants, coating asphalts and ing as well as specifications ven. sumé léfinition des toitures bituse historique du développe- :es et des effets que la dé- uts et des bitumes qu'on en rs de ce développement. ropriétés essentielles à conbitumes pour la fabrication et de bardeaux asphaltés et adigeonner dans les toitures ne enfin des tableaux énond'enduits saturants typiques et de bardeaux, de bitumes iitures rapportées ainsi que pour leur achat. istorical 1 in roofing for more than t until sixty years ago that weloped which, because of began to replace the other j such as wood shingles that iy up to this time. In 1844 erproofed by passing them Some of this material was ns-Manvilk Corporation, New zpplied as roofing with pine tar and similar materials as mopping cements. Some time between 1844 and 1880, roofing felts were developed. With their advent the laminar type of built-up roofing consisting of alternate layers of saturated felt and hot coal tar pitch mopping material became more common as the covering for flat roof surfaces. Between 1880 and 1890 asphalt began to replace coal tar pitch as the mopping cerncnt in this construction which has not been changed materially since then except for the development of better felts and more durable asphaltic materials.
The first asphalt "ready" or "prepared" roofings in any way similar to current products were produced in 1893. These roofings were known as "composition" or "rubber" roofings. They consisted of asphalt saturated and coated felts surfaced with fine sand or talc in order to prevent sticking in the package. This roofing was readily accepted chiefly because it could be purchased in roll form and applied by the consumer himself. But while this roofing performed its primary function of keeping the interior of the building on which it was applied dry, and it was fairly durable, its use was limited because of its color and appearance.
In 1901 the first asphalt shingles were produced by cutting roll roofing into individual units simulating wood and slate shingles in size and shape and which could be applied in a manner similar to them. But it was not until 1911 that shingles of this type began to be produced generally throughout the industry. This change in form coincided with the introduction of asphalts more suitable for the manufacture of ready roofings and followed by two years the adoption of natural slate granules as surfacing materials. These changes improved the durability and appearance of asphalt roofings tremendously, gave this choice of three permanent colors-graq black and. red-and the consumption o ioofings began to increase rapidly so 2