Finally tackled that metal edging thing on my roof

White coatings sound great on paper, but in practice, they just don’t last in our weather.

- "White coatings sound great on paper, but in practice, they just don’t last in our weather." - man, you nailed it. I’ve seen more flaking white roofs than I care to count.
- Prep feels like a slog, but skipping it is like duct-taping a boat... sure, it floats for a minute.
- If you made it through cleaning and still had the energy to actually finish the edging, you deserve a medal. Or at least a cold drink.
- Weather here eats shortcuts for breakfast. You’re not alone.

- I get the doubts about white coatings, but I’ve seen a couple in my neighborhood last 5+ years with regular touch-ups.
-

Weather here eats shortcuts for breakfast.

- I get the doubts about white coatings, but I’ve seen a couple in my neighborhood last 5+ years with regular touch-ups.

- That “weather eats shortcuts for breakfast” line hits home. I’ve watched a few neighbors repaint their metal trims every couple years, but one guy down the street swears by a certain primer and his still looks decent after 6 years.
- Anyone here tried the cheaper coatings vs the high-end ones? I’m always tempted by the price difference, but worried about having to redo it sooner.
- Is it mostly about the prep work, or does the brand really matter long-term? I’d rather not spend double if I don’t have to...

I’ve managed a few properties with metal trim, and honestly, prep work makes or breaks it. I’ve seen cheap coatings last surprisingly well if the surface was cleaned and primed right, but if you skip steps, even the expensive brands won’t hold up. That said, some of the high-end primers really do seem to bond better, especially in areas with wild temperature swings. I get the temptation to save money, but sometimes it’s worth spending a bit more up front just to avoid the hassle of redoing it every couple years.

I’ve seen cheap coatings last surprisingly well if the surface was cleaned and primed right, but if you skip steps, even the expensive brands won’t hold up.

That’s been my experience too, especially on jobs where folks want to cut corners. I’ve seen some “budget” paints outlast the pricier stuff just because someone took the time to really get all the grime and oxidation off first. Wild how much difference a wire brush and some elbow grease can make.

I’m curious though - what kind of primer are you using for those spots with big temp swings? I’ve tried a couple different brands (Rustoleum, Zinsser, even some of the more industrial ones), but sometimes I still get a bit of peeling after a couple seasons, especially on south-facing trim that bakes in the sun all summer and then freezes all winter. Maybe it’s just our crazy freeze-thaw cycles up here, but I haven’t found a “set it and forget it” solution yet.

Also, do you bother with two coats of primer or just one? Some folks swear by double-priming, but honestly I’ve only done that when the metal was in rough shape to start with. Most of the time I’m just trying to keep water from sneaking under the edges and causing rust.

One thing I haven’t totally figured out: is it better to use those self-etching primers on older trim, or stick with the regular stuff? I’ve had mixed results - sometimes it bonds like crazy, other times it seems like overkill.

Anyone else dealing with weird bubbling or flaking after a winter or two? Or maybe that’s just our local weather doing its thing...

- Gotta say, I've had the opposite experience with "budget" paints sometimes. Even with solid prep, a few of those cheaper coatings just couldn't handle our wild temp swings. Maybe it's the brand, or maybe it's just the way our weather hits different.

-

“I’ve tried a couple different brands (Rustoleum, Zinsser, even some of the more industrial ones), but sometimes I still get a bit of peeling after a couple seasons, especially on south-facing trim...”

- Two coats of primer? Only if the metal’s really rough or pitted. Otherwise, I stick with one and just make sure it’s a good even layer. Double-priming hasn’t made a huge difference for me unless the surface was in bad shape.

- Self-etching primer - mixed bag. Works great on bare, shiny metal, but if there’s any old paint or rust left, it can actually make things worse. I usually only break it out for new installs or spots I can sand down to bare metal.

- Bubbling and flaking still happen, especially with the freeze-thaw. Sometimes it’s just the nature of the beast in these climates. I’ve started using a flexible sealant under the edges to help keep water out, and that’s cut down on rust creeping in from underneath.

Not a perfect system, but it’s helped.

Bubbling and flaking still happen, especially with the freeze-thaw. Sometimes it’s just the nature of the beast in these climates.

That’s the truth. I see a lot of folks get frustrated when they do everything “by the book” and still end up with some peeling or rust creeping in after a couple of seasons. It’s tough to beat Mother Nature, especially on those south-facing edges where the sun just cooks everything. You’re not alone there.

Using a flexible sealant under the edges is a solid move. I’ve seen that help slow down the rust on a few jobs, especially where water likes to sneak in. Epoxy-based primers are a bit of an investment, but they really do seem to hold up better when you’ve got wild temp swings and all that UV exposure.

Honestly, even the best prep and products can only do so much with the kind of weather swings we get. Sounds like you’re doing all the right things - sometimes it’s just about maintenance and catching issues early before they get out of hand. Don’t get discouraged if it’s not perfect. That metal edging is always going to be a bit of a battle, but you’re definitely ahead of the curve.

I get what you’re saying about epoxy primers and flexible sealants, but honestly, I’m not convinced the extra cost is always worth it for everyone. I tried the “premium” route on my garage roof a few years back - followed all the advice, spent a small fortune - and still had to touch up rust spots after two winters. Sometimes I wonder if just sticking with basic paint and doing a quick check every spring isn’t a better use of time and money. Maybe it’s just my luck, but the fancy stuff hasn’t lasted much longer for me.