Our shingles are not one-sixth the weight of slate, which greatly reduces
the cost of the frame-work of roof. They readily conform to the shape of
a roof, which slate will not do. Slate is not thoroughly fire-proof, as
heat from an adjoining building on fire will cause the slate to crack,
which would destroy the best roof in a few minutes, leaving the sheeting
exposed. Especially is this the case if water is thrown on them while hot.
Our shingles are free from the many accidents to which slate roofs are
liable, such as cracking from shrinkage of wood-work to which they
are attached; breaking, caused by necessary repairs to the valleys or
chimneys; and the effect of frost on defective slate. Such defects cannot
always be avoided by ordinary observation. All builders of experience are
aware of the expensive repairs necessary to keep a slate roof in good
order, but perhaps the most inconsistent thing connected with the whole
roofing business is the fact that nineteen-twentieths of all the houses
covered with slate =have gutters lined with the same material of which
our shingles are made=, while slate was used for covering because of its
supposed durability.
Should anything fall on our shingles it would probably dent them
without causing a break; but should it perforate them, the shingles can
be replaced by another, or a leak can be soldered, and fire from an
adjoining roof cannot more than injure the paint. They will cool off
rapidly, retaining their shape.