The Repair, Replacement Jeffrey S.
& Maintenance of Historic
of Slate Use
Does Slate Come From?
of Slate and Slate Roofs
Replacement of Deteriorated Roofs
Given the relatively high initial cost of installing a new slate roof,
it pays to inspect its overall condition annually and after several
storms. For safety reasons, it is recommended that building owners and
maintenance personnel carry out roof surveys from the ground using
binoculars or from a cherry picker. Cracked, broken, misaligned, and
missing slates and the degree to which delamination has occurred should be
noted, along with failed flashings (pin holes, open seams, loose and
misaligned elements, etc.) and broken or clogged downspouts. A roof plan
or sketch and a camera can aid in recording problems and discussing them
with contractors. In the attic, wood rafters and sheathing should be
checked for water stains and rot. Critical areas are typically near the
roof plate and at the intersection of roof planes, such as at valleys and
hips. Regular maintenance should include cleaning gutters at least twice
during the fall and once in early spring, and replacing damaged slates
promptly. Every five to seven years inspections should be conducted by
professionals experienced in working with slate and steep slopes. Good
record keeping, in the form of a log book and the systematic filing of all
bills and samples, can help in piecing together a roof's repair history
and is an important part of maintenance.
As part of regular maintenance, an attempt should be made to keep foot
traffic off the roof. If maintenance personnel, chimney sweeps, painters,
or others must walk on the roof, it is recommended that ladders be hooked
over the ridge and that the workmen walk on the ladders to better
distribute their weight. If slates are to be walked on, it is best to wear
soft soled shoes and to step on the lowermiddle of the exposed portion of
the slate unit.