You nailed it about the trade-off. I’ve seen a lot of folks get frustrated with how fast EPDM breaks down, especially on south-facing slopes. Silicone’s not perfect, but like you said, at least you’re not climbing up there every year. Pre-bending flashing is awkward, no doubt—on a 10/12 pitch, it feels like you need three hands. Still, I’d rather wrestle with that than chase leaks after every storm. It’s just one of those necessary evils if you want to keep things dry.
I hear you on the pre-bending—on a steep pitch, it’s like a wrestling match with gravity. I’ve found if you cut a template out of thin plywood first, it helps get the angle right before you try to shape the metal. Saves a lot of cursing and wasted flashing. Silicone boots hold up better for me too, especially in spots that get hammered by sun all year. EPDM just doesn’t seem to last more than a couple seasons on those slopes, no matter what the packaging claims.
Silicone boots hold up better for me too, especially in spots that get hammered by sun all year. EPDM just doesn’t seem to last more than a couple seasons on those slopes, no matter what the packaging claims.
Yeah, same here—EPDM just bakes and cracks in our summers. I switched to silicone a few years back and haven’t looked back. The only hassle is getting them to seat right on the older metal roof, but at least I’m not replacing them every spring. That plywood template trick is gold, by the way. Saved me from mangling a bunch of flashing last time.
Getting silicone boots to sit right on older metal roofs is such a pain—I feel that. I’ve fought with more than a few, especially when the panels aren’t exactly flat or have those weird old seams. Still, way better than dealing with EPDM splitting before you even make it through one winter and summer cycle. Pretty sure I’ve got a graveyard of cracked ones in my shed.
That plywood template idea is genius. I tried free-handing the first time and just ended up with a boot that looked like it’d been chewed by raccoons. Since switching to templates, it’s way less stressful.
One thing I noticed, though—if you’re up north, sometimes silicone gets stiff in the cold and doesn’t want to flex back into place after you move it around. Not a huge deal, but worth watching out for if you’re working in early spring or late fall. Still beats crawling around patching leaks every season...
- Not sure I’d call silicone boots a clear win over EPDM in every case.
- Seen plenty of “permanent” silicone boots start leaking after a couple freeze-thaw cycles, especially on roofs with a lot of movement.
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“Still beats crawling around patching leaks every season...”
- Maybe, but if you’re in a spot with big temp swings, you might just be trading one hassle for another.
- Sometimes a good old-fashioned lead boot (if you can find one) outlasts both, especially on older metal.
- Templates help, but if the roof’s wavy or seams are high, nothing sits perfect.
- Just my two cents—sometimes the “upgrade” isn’t always less work in the long run.
