Natural or synthetic
| Natural slate | Synthetic slate | |
|---|---|---|
| Installed, per sq ft | $20 to $40 (Rapid Roofing) | $9 to $16 (Rapid Roofing) |
| Weight, per 100 sq ft | 800 to 1,000+ lbs | About 300 lbs (Brava) |
| Lifespan | 75 to 100+ years | 30 to 50 years |
| Framing | Often needs an engineer and reinforcement | Usually fine on a house framed for shingles |
All American Home Improvement breaks natural slate down further: $9 to $20 a square foot for the slate itself, $5 to $10 to install it, and $1,000 to $10,000 if the framing needs work. Their total for most homes is $30,000 to $70,000.
Synthetic slate is molded to look like stone. Rapid Roofing rates Brava for winds up to 188 mph with ring-shank nails and gives it a Class 4 impact rating. GAF Slateline is cheaper still, but Rapid points out it is really a designer asphalt shingle, not a composite.
The weight question
This is the first thing to settle if you want real slate on a house that does not have it. Rapid Roofing says natural slate puts three to four times the load on a roof that it was typically designed for, and that most homes built from the 1950s through the 1990s were framed for shingles. That means an engineer’s review and, often, new rafters. It is why a lot of Long Island homeowners who love the look end up with synthetic.
Repair before you replace
A slate roof that is 80 years old is not necessarily done. The stone often outlasts the nails, the flashing and the occasional cracked piece. Broken and missing slates can be swapped out individually, and the copper flashing around chimneys and valleys can be redone. Rapid Roofing notes this is work for specialty slaters, who charge premium rates. All American warns that new slate rarely matches weathered slate exactly.
No Long Island company we found publishes slate repair prices. Expect a site visit before anyone gives a number.
Find a slate specialist
Do not hand a slate roof to a crew that mostly does shingles. Walking on slate breaks it, and the repair methods are different. Long Island companies that advertise slate as a specialty include John G. Hubler and Sons in Rockville Centre, which has done slate since 1973, and Tascone Contracting, which works on slate and copper. Ask any company how many slate jobs it did last year and for an address you can drive past.
