Slate Roofing

Weight first

Natural slate is far heavier than composition shingle — by a large multiple, depending on thickness and coursing. Most Sacramento homes were not framed for it, and putting it on a house that cannot carry it is a structural problem, not a roofing one.

Before any slate proposal means anything, the framing has to be assessed, and on many houses that means an engineer. If a contractor quotes natural slate without raising structural capacity, that is the moment to stop.

Synthetic slate

• Composite or polymer slate at a fraction of natural weight, installable on ordinary framing
• Consistent thickness and coursing, which reads more regular than natural slate up close
• Long manufacturer warranties, though not the multi-century life of real stone
• Substantially lower installed cost, because it does not need a slater
• The usual right answer for a Sacramento home that wants the look

Repairing existing slate

Older Sacramento homes with real slate do exist, and most of what they need is repair rather than replacement. Individual slates are replaced with a slate hook or a copper strap — never with sealant or a nail through the face.

The commonest cause of failure on an old slate roof is not the slate. It is the flashings and the nails, both of which have shorter lives than the stone, and both of which can be renewed.

Walking a slate roof

Slate breaks underfoot. Any trade that needs roof access on a slate house — solar, HVAC, chimney, antenna — should be told so in advance, and should be using ladders and pads rather than walking the field. Most damage we repair on slate roofs was done by someone servicing something else.

Common questions