The biggest misconception in residential roofing: the tile keeps water out.
It doesn't. Tile sheds water — but enough always gets through that the
underlayment beneath the tile is the actual waterproofing layer. And
that underlayment is often only rated for 25 years.
Concrete and clay tile lasts 50–100 years. The underlayment fails at 25.
Most NAZ tile roofs installed 1995–2005 are reaching this end-of-life
window in 2026 — and most owners have no idea.
How to know if it's failing
Sign 1: Stains on stucco fascia
Look at the underside of your eaves. Brown drip stains on stucco or
wood fascia, particularly below valleys, indicate water moving where it
shouldn't. The water came from a failing underlayment.
Sign 2: Stains in attic on rafters
Get in the attic on a sunny afternoon. Look for water stains on the
rafters or sheathing. Brown = past leak. Wet/dark = active leak.
Sign 3: Cracked or curled tile
Walking the roof — which only a pro should do — and finding many
cracked tiles is a sign that prior repair attempts have failed. Tile
cracks happen naturally; many cracked tiles in one area is a flag.
Sign 4: Visible felt at edges
Lift an edge tile or look at the rake. If the underlayment is brittle,
cracked, or has tar paper showing instead of synthetic, it's likely
end-of-life.
Sign 5: Tile slipping
Tile is held in place by either gravity, mortar, or hurricane clips.
Slipped tile (especially at hips and ridges) often indicates a failing
mortar bed because the underlayment beneath has deteriorated.
The "tile relay" — what it is and what it costs
Tile relay = strip the existing tile, replace the underlayment, reuse
the same tile.
Cost in 2026 (Prescott metro, 25-square house):
- Tear-off (with care to preserve tile): $1,800
- New underlayment (synthetic double-layer): $4,200
- Battens and accessories: $1,400
- Tile reinstall labor: $5,800
- Replacement tile (typical 5–8 % loss): $1,200
- Permit, dump, contractor markup, AZ tax: $4,100
- Total: $18,500
Compare to full new-tile replacement: $24,500. Relay saves $6,000+ if
your tile is in decent shape.
Eagle, Boral, and Westile all carry "field tile match" stock for
common AZ profiles. Match availability is good through about 2010
installs; older tile often needs blending strategy.
When NOT to relay
- >15 % of tile broken or cracked → buy new tile, relay isn't economical
- Tile is discontinued profile with no match → cosmetic risk
- Underlayment damage indicates deck rot → deck replacement needed first
- Roof is 30+ years old AND tile shows surface erosion → replace whole
Underlayment options for the relay
Don't cheap out here. The underlayment is the actual roof.
| Option | Service life | Cost premium | NAZ recommendation |
|---|---|---|---|
| 30-lb felt (single) | 12–18 yrs | Cheapest | Avoid |
| 30-lb felt (double) | 18–22 yrs | +$0.30/sf | OK budget |
| Synthetic single | 25–30 yrs | +$0.55/sf | Good |
| Synthetic double | 35–40 yrs | +$1.10/sf | Best for relay |
| Self-adhered SBS | 40+ yrs | +$2.20/sf | Overkill (use in valleys only) |
"Synthetic double-layer" is the 2026 standard for tile underlayment
replacement in Northern Arizona. It costs 30 % more than minimum code
and lasts twice as long. Don't accept anything less.
What to do this month
- Look at your fascia from the ground for drip stains
- Get in your attic and look at rafter undersides
- If you see anything: book a $149 tile-lift inspection from a NAZ
roofer. They lift 4–6 tiles, photograph the underlayment, and
give you a written assessment.
The cost difference between relay (~$18.5k) and a full leak-and-rebuild
after deck rot (~$32k+ with interior repairs) is your reason to
inspect this year.