What decking is and why it rots here
Decking is the plywood or board layer the shingles are nailed to. It is what makes a roof solid underfoot. When it goes soft, new shingles have nothing to hold onto, so it has to be replaced before the new roof goes on.
In our climate it is usually long-term moisture that does it. A small leak nobody noticed, an attic that does not breathe, or debris sitting in a valley holding water against the roof through years of humidity. That is one reason maintenance is worth doing while a roof is still sound.
How we handle it, and how we price it
- We agree a per-sheet price before the job starts, so there is no invented number later.
- We show you the rotten sheets. You see what you are paying for.
- We replace only what is actually soft, not the whole deck by default.
- If we find widespread rot, we stop and talk to you before continuing.
This is the single most common reason a reroof costs more than the original quote. We would rather warn you it is possible than surprise you with it. See asphalt shingle replacement for how the rest of the job runs.
Common questions
Can you tell me about decking before the job starts?
Not with certainty. Decking sits under the shingles, so nobody can see it until tear-off. Anyone who quotes it as a fixed number before opening the roof is guessing.
How do you charge for it?
By the sheet, at a price agreed before we start. You see the rotten sheets before they go in the skip.
What causes it here?
Long-term moisture. A small leak nobody noticed, poor attic ventilation, or debris holding water against the roof for years.