Does the roof deck need repairs before metal roofing is installed?
Any rotten, delaminated, soft, badly uneven or structurally inadequate decking should be corrected before the new roof is completed. Metal panels need the substrate and fastener holding specified by the manufacturer or design professional.
What affects the answer?
- Plywood or board condition and thickness
- Moisture staining or decay
- Fastener withdrawal resistance
- Flatness for broad panels
- Rafter or truss movement
- Past leaks at valleys and penetrations
What homeowners should understand
Deck repair is easiest to verify after tear-off. The contract should state the included allowance or unit price for replacement material and explain who authorizes extra work. Structural sagging, widespread decay or altered framing may require an engineer or qualified building professional.
Do not trap wet materials under a long-life roof. Identify and fix the moisture source—leakage, condensation or interior air movement—before closing the assembly.
Questions to ask your roofing contractor
- What deck condition is required by the roof manufacturer?
- How will repairs be measured and approved?
- Is structural review needed anywhere?
The bottom line
A permanent roof deserves a sound, dry and properly fastened deck. Correct hidden problems before the metal conceals them.