I've noticed something similar in my own house. We had thick blackout curtains in our bedroom, and the windows behind them always seemed damp or foggy, especially during winter. At first, I thought it was just poor insulation or something, but after switching to lighter curtains and leaving them open more often, the condensation issue improved a lot.
"Could it be related to airflow or sunlight exposure?"
I think you're onto something here. Heavy drapes probably trap moisture against the glass and limit airflow, creating a perfect environment for condensation and mold growth. Sunlight might also help dry out any moisture that does collect on the window surface. Regular cleaning definitely helps, but I've found that combining it with better airflow and lighter window coverings makes a noticeable difference.
It might not be as critical as regular maintenance or drainage checks, but it's definitely worth considering if you're trying to extend your windows' lifespan.
I've noticed something similar myself, but I'm not entirely convinced sunlight alone makes a huge difference. Sure, airflow helps—no doubt about that—but could the window frame material also play a role? My old wooden frames seemed to have more condensation issues compared to the newer vinyl ones. Maybe certain materials just handle moisture better?
"Heavy drapes probably trap moisture against the glass and limit airflow"
Definitely agree with this though...heavy curtains made things worse for us too.
I've noticed the same thing about wooden frames—they definitely seem to soak up moisture more easily. Switching to vinyl made a noticeable difference for us too. Also, cracking the window open just a tiny bit overnight helped cut down condensation quite a lot...
"Switching to vinyl made a noticeable difference for us too."
Vinyl definitely has its perks, but honestly, I found aluminum frames to be even better at handling moisture. We had vinyl installed in our last place, and while it was an improvement over wood, we still saw some condensation build-up during colder months. When we moved, we decided to give aluminum a shot—mostly because a friend recommended it—and I've been pretty impressed. They're lightweight, durable, and seem to handle temperature swings without much fuss. Plus, they're surprisingly easy to maintain.
About cracking windows open overnight... I get the logic behind it, but personally, I found it just made our heating bills spike in winter. Instead, we invested in a decent dehumidifier for the bedroom. It pulls moisture out of the air without letting cold drafts in. Might not be everyone's solution, but it's worked well for us so far.
"Instead, we invested in a decent dehumidifier for the bedroom."
Yeah, totally agree on the dehumidifier route. We had vinyl windows too, and while they were decent, condensation was still an issue. Aluminum frames are solid, but I've actually found fiberglass frames to be even better—super durable and handle moisture like a champ. Also, quick tip: regularly wiping down window sills helps a ton. Learned that the hard way after dealing with mold spots one winter... not fun.
Interesting points about fiberglass frames—I haven't tried those yet. But honestly, I've found that even with a good dehumidifier, airflow makes a huge difference. We started cracking our windows open just a tiny bit during the day (even in winter), and it noticeably reduced condensation buildup. Sure, it's not ideal for heating bills, but it beats dealing with mold spots again... been there too, unfortunately.
"regularly wiping down window sills helps a ton."
Definitely agree here—it's tedious but worth it.
Cracking the windows open slightly is a solid tip—I've recommended that to clients dealing with condensation issues plenty of times. Sure, it feels counterintuitive when you're trying to keep heating costs down, but mold remediation is way pricier in the long run. Have you tried using those small moisture absorbers (like DampRid) near problem windows? They're not miracle workers, but they can help a bit, especially in rooms where airflow is limited.
Also, totally agree about wiping down window sills regularly. It's one of those chores nobody enjoys, but it really does extend the life of your windows. Have you noticed if certain rooms or window orientations (north-facing vs south-facing) have more condensation than others? Sometimes just figuring out the pattern can help you tackle the issue more effectively. Anyway, sounds like you're already on the right track—good luck!
Cracking windows open does help, but honestly, as someone who's still adjusting to homeownership (and the bills that come with it), I'm a bit skeptical about how practical this is in colder climates. I tried it last winter, and while condensation improved slightly, my heating bill noticeably jumped—so it's kind of a trade-off.
One thing I've found helpful instead is running a small fan pointed at the windows during peak condensation hours—like early mornings. It circulates air without letting in freezing drafts. Those moisture absorbers you mentioned are decent, but personally, I got tired of replacing them all the time. Eventually invested in a basic dehumidifier for the worst room (north-facing bedroom... figures!), and it's been surprisingly effective.
Also, wiping down window sills regularly is great advice, but let's be real—it's one of those chores I conveniently "forget" until mold starts to wave hello at me from the corners. Maybe that's just me though...
Totally feel you on the mold waving hello thing... I swear mine started sending greeting cards last winter. I tried the cracked window trick too, but my wallet cried every time the heating bill arrived. Ended up grabbing some cheap thermal curtains—honestly didn't expect much, but they've helped keep the condensation down a bit without freezing me out. Still gotta do the dreaded window wipe-down occasionally, though... adulting is rough sometimes.
I've battled the mold greeting committee myself, and honestly, thermal curtains are a decent start but won't fully solve the issue. Years ago, I installed some inexpensive window film insulation kits—basically clear plastic sheets you shrink-wrap onto the window frame with a hairdryer. Sounds gimmicky, but it significantly reduced condensation and drafts. Still gotta wipe occasionally, but way less often. Worth a shot if you're tired of mold pen pals and hefty heating bills...