I’ve actually installed a few of those self-regulating heat cables on some older copper lines last winter. They’re pretty slick—don’t get hot unless it’s actually cold enough, so you’re not just burning electricity for nothing. One thing I noticed, though, is you’ve gotta make sure the insulation over them is solid, otherwise you’re still losing heat to drafts. Had a spot under my uncle’s porch where the cable worked fine but the wind just cut right through and froze the pipe anyway. Guess there’s no real substitute for tracking down every little air leak...
Yeah, those heat cables are a game changer—until you realize wind is basically Mother Nature’s way of trolling plumbers. I learned the hard way that even the fanciest cable won’t save you if there’s a draft sneaking in. I’ve started using that spray foam in a can for the worst gaps, especially under decks and porches. It’s messy, but it beats crawling under there in January with a hair dryer... again.
I get the appeal of spray foam—quick fix, fills gaps, all that. But I’ve had mixed feelings about it, especially after seeing how it breaks down over time and can trap moisture if you’re not careful. I started using mineral wool insulation for those tricky spots under the porch. It’s not as fast, but it holds up better in the long run and doesn’t off-gas. Plus, if you ever need to get back in there, you’re not chiseling out a sticky mess. Just my two cents from a few too many winter plumbing “adventures.”
I get where you’re coming from with mineral wool—it’s definitely easier to work with if you ever need to get back in there. But I’ve actually had decent luck with closed-cell spray foam, especially in spots where airflow is a bigger concern than moisture. The trick is making sure everything’s bone dry before you seal it up, and not overdoing it. I’ve seen folks go overboard and end up with a soggy mess, but a light hand and some patience can go a long way. For me, it’s about matching the material to the job, even if it means mixing things up under the porch.
The trick is making sure everything’s bone dry before you seal it up, and not overdoing it.
Yeah, learned that the hard way after a crawlspace “science experiment” last spring—let’s just say mold loves a heavy hand. I still lean mineral wool for spots I might need to revisit, but mixing materials does work if you’re careful. Just don’t let the foam turn into a marshmallow factory... been there, regretted that.
