Making sure the deck’s ready for underlayment - what’s your process?

Funny how a board can look fine until you give it a poke, huh? I’ve run into the same thing - sometimes the “good” ones are the worst. I’m big on checking for mold too, especially after storms. Even if it’s just a little soft, I’d rather swap it out now than deal with leaks later.

Even if it’s just a little soft, I’d rather swap it out now than deal with leaks later.

I get what you mean, but sometimes I wonder if I’m being too picky. Like, if a board’s just barely spongy at the edge, is it always worth replacing? Some of the older guys on site will just reinforce from underneath if it’s not too bad. Do you ever do that, or is it always a full swap for you?

If it’s just a little spongy right at the edge and there’s no visible rot, I get why some folks just reinforce. I’ve done that myself on a couple old houses where replacing the whole sheet would’ve meant tearing into a lot more than I wanted. Still, I lean toward swapping out if there’s any real give, especially in our wet climate. Once moisture gets in, it never really stops. But yeah, sometimes you’ve gotta balance time and budget... Not always a clear answer.

I get nervous about even a little bit of sponginess, honestly. Maybe it’s just my paranoia as a first-timer, but I keep picturing water sneaking in and wrecking everything from the inside out. I patched a spot last fall, but now I’m second-guessing whether I should’ve just replaced the whole section. The budget’s always the kicker though...

Sponginess always makes me uneasy too, and I’ve been through a couple deck rebuilds now. Once, I tried patching a soft spot to save some cash, but the rot just kept spreading underneath. Ended up replacing a bigger chunk the next year anyway - cost me more in the long run. If your patch feels solid and dry, you might be fine for a while, but I’ve learned that if there’s any give, water will find its way in eventually. Sometimes it’s worth biting the bullet if you can swing it.