Warehouses require rat proofing because of the great quantities of
foodstuffs handled there and even stored for long periods. It is
essential that the building itself be rat proofed with concrete or
masonry foundation, concrete floors, and tight-fitting doors lined with
metal at the base. Doors of warehouses frequently become jammed as a
result of heavy trucking and should be carefully watched for defects
that would admit rats. Concrete floors, in addition to being rat proof
and fire proof, save labor because of the comparative ease with which
loaded trucks can be rolled over them.
When warehouses are found to be seriously infested with rats, the
trouble can usually be traced to such faulty construction as allows the
rats access to spaces beneath floors or within walls, or even provides
exits to near-by shelter outside.
Eats also gain entrance to rat-proofed warehouses through being shipped
in with produce or when doors are left open, and once inside they may
persist and do much damage from shelter afforded by piles of stored
goods. Such damage, however, is usually small in comparison with that
resulting from permanent rat harbors beneath floors, and the rats
can be destroyed much more easily. A report from one flour warehouse
indicated that it cost more than $3,000 a year to repair bags gnawed
by rats and mice. Such a loss would go far toward rat proofing any
premises. A common cause of rat depredations in warehouses is the
construction of platforms a few inches off the floor upon which to pile
flour and other produce. Such platforms provide permanent shelter for
rats and should be eliminated. Boards may be laid flat on the concrete
floor with no spaces between them to afford rat harbors; or, if this is
not sufficient proof against dampness, the platforms should be raised
a foot or more off the floor to admit light. In such a place a rat
does not feel safe and will not stay. Bags of flour, grain, and other
produce furnish harborage that can not well be avoided, but such goods
are usually moved so frequently that rats do not have opportunity to