Slate & Cedar Roofing: what to expect
Slate fails at the fasteners, not the stone
Good slate outlives the people who installed it. What fails first is almost always everything around it: the nails corrode, the flashing in the valleys and around the chimney rusts through, and the sheathing beneath softens. A slate roof shedding tiles is usually telling you the fasteners are gone, not that the slate is worn out. Selective replacement with matched salvage or new slate, plus new copper or lead-coated flashing, frequently buys decades more.
Cedar needs to breathe
Cedar shakes and shingles depend on drying between wettings. Trapped moisture, from moss, from debris packed into the keyways, from an overlay that blocked airflow underneath, from overhanging branches keeping a slope permanently shaded, is what rots them. Cedar on a Connecticut roof also takes hard UV in summer and constant freeze-thaw in winter, so maintenance intervals are shorter than for asphalt.
Getting the right contractor
Ask directly how much slate or cedar work the contractor does, and ask to see recent examples. Walking a slate roof incorrectly breaks slates; patching slate with asphalt or the wrong sealant creates a repair that fails within a few seasons and damages the surrounding tiles. If the house is in a historic district, check whether local review applies before material is changed.
Typically included
- Selective slate replacement with matched material
- Copper, lead-coated and stainless flashing renewal
- Cedar shake and shingle repair and replacement
- Moss, debris and drainage remediation
- Assessment of sheathing and fastener condition
- Guidance where historic district review may apply