Case Study: What Rotten Roof Decking Really Looks Like (And How We Fix It)

The Problem

This roof wasn’t “just old.”

It had:

  • Rotten decking at the chimney
  • Failed flashing
  • Long-term moisture at the eaves
  • Soft sheathing along the gutter line
  • Wet insulation below

From the ground, it looked like a normal replacement.
Once we tore it off, the real story showed up.

This is common. Roof leaks rarely stay in one spot.

What Caused It

  1. Improper chimney flashing – No true step flashing system, just surface metal.
  2. Water backing up at gutters – Rot along the drip edge and fascia line.
  3. Aging underlayment – No secondary protection once shingles failed.
  4. Slow leaks over time – Not a storm issue. A maintenance issue.

Rot is almost always slow and quiet.

Our Fix

We don’t cover rot. We remove it.

Step 1 – Full tear-off
All shingles, felt, and compromised decking removed.

Step 2 – Structural inspection
Checked rafters, tails, and nailers for integrity.

Step 3 – Replace damaged decking
New sheathing installed with correct fastening schedule.

Step 4 – Proper flashing system

  • True step flashing at chimney
  • Counter flashing integrated into masonry
  • Ice & water membrane at penetrations and valleys

Step 5 – Synthetic underlayment + full system install

No shortcuts.

Why This Matters

If you shingle over soft decking:

  • Nails won’t hold properly
  • Shingles will lift in wind
  • Leaks return
  • Warranty can be voided

A roof is only as good as what it’s attached to.

The Result

  • Solid, dry substrate
  • Correct water management
  • Proper load support
  • Roof system built to last

This wasn’t just a re-roof.
It was a structural correction.

That’s the difference between replacing shingles — and building it right.

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If you’ve gotten a roof quote and thought, “That’s higher than I

The Problem We were called to a condo with a serious

Most roofing problems aren’t shingle problems.They’re system problems. A roof only performs