Roofing

Water doesn’t drip straight down from where it gets in; it follows the wood, which is exactly why the rot found during a repair often surprises everyone.

Rot isn’t just wood getting wet; it’s a living organism actively feeding on the wood, and it needs a very specific set of conditions to do it.

There isn’t one single answer; there’s a timeline with two very different milestones, and knowing both changes how urgently you should actually react.

Whether the wood comes back fine or not comes down almost entirely to how wet it got and how long it stayed that way before drying started.

Mold on sheathing is often the early warning telling you conditions are heading toward something far more destructive, not the destructive thing itself.

The screwdriver test roofers actually use settles this in seconds: if it sinks in easily, sanding won’t save that panel.

The swelling isn’t random; it’s the direct, physical consequence of how OSB is manufactured, and it explains why edges swell worse than the panel center.

By the time damage is visible from the outside, the sheathing has often been wet for a long time already, since the earliest signs hide underneath.

Two contractors can describe the exact same wood as decking and sheathing in the same sentence, and both would be correct.

It’s doing two jobs at once: a flat surface for the roofing material, and a structural diaphragm holding the whole frame square under wind load.