I insulated mine last year—honestly, wasn't that expensive. Grabbed some basic duct wrap from the hardware store, spent maybe $25 total. Noise-wise, it's noticeably quieter...fan doesn't sound like a jet engine anymore, thankfully. Worth it imo.
Did pretty much the same thing last month. Grabbed some duct insulation from Home Depot, cost around $30ish, and it took maybe an hour tops. Definitely quieter now, but I also noticed it seems to help a bit with condensation too. Before insulating, I'd sometimes see droplets forming on the ceiling around the fan after a hot shower—haven't spotted that since wrapping it up. Curious if anyone else noticed this?
Quick tip for anyone planning to do this: make sure you clean off any dust or grime from the duct first, helps the insulation stick better and prevents mold buildup down the line. Learned that one the hard way during my apprenticeship...nothing worse than having to redo a job because of shortcuts.
Yeah, insulating the duct definitely helps with condensation. Seen it plenty of times—warm, humid air hitting cold metal ducts is a recipe for moisture. Good call cleaning it first too... shortcuts always come back to bite ya later.
Insulating ducts is definitely a smart move, especially in bathrooms where humidity levels spike regularly. Condensation issues can be sneaky—sometimes you don't even realize there's a problem until you spot mold or water stains. Cleaning the ducts beforehand was a great decision too; I've seen plenty of cases where folks skip that step, thinking insulation alone will solve everything. Unfortunately, dirt and debris trapped inside can still cause airflow issues and even odors down the line.
One thing I'd add from experience: make sure your bathroom exhaust fan is properly sized for the space. Even with insulated ducts, if your fan isn't strong enough to pull out moisture quickly, you'll still get condensation buildup over time. A good rule of thumb is to match the fan's CFM (cubic feet per minute) rating to your bathroom's square footage—so if you've got an 80 sq ft bathroom, aim for at least an 80 CFM fan. And if you've got a particularly steamy shower or multiple showerheads, bumping up to a slightly higher rating won't hurt.
Also, double-check that your ductwork has as few bends and turns as possible. Every bend reduces airflow efficiency and increases the chance of moisture lingering inside the duct. If you can't avoid bends entirely (and let's face it, sometimes that's just how houses are built), try using smooth metal elbows instead of flexible ducting—they're easier to insulate properly and less likely to trap moisture.
Sounds like you're already on top of things though... nice job getting ahead of potential problems before they become headaches later on.
Good points all around, but I'm curious—did anyone mention vent placement yet? I've seen bathrooms with fans installed way off in a corner or too far from the shower area, and even a strong fan struggles to clear moisture effectively from there. Getting the vent close to the main source of humidity can make a huge difference. Did you have to move your fan location during the reno, or was the original placement already solid?
