I'm old enough to remember when single-pane jalousie windows were the norm here in Florida (you know, those crank-out glass slat windows). I replaced a bunch of those on my porch with modern windows, and boy, the difference is night and day. No more sweating in that room during summer. It's like we gained extra living space because we can actually use the porch year-round now.
Just a testament to how far window tech has come. If anyone out there still has old jalousies or single panes, don't hesitate to upgrade – the improvement is huge.
From an HVAC perspective, I love seeing folks upgrade their windows. As an AC tech in FL, I often size new AC systems for homes, and when a home has new efficient windows versus old leaky ones, it can sometimes allow for a smaller AC unit or at least reduces the strain on it. I had a customer who replaced windows and we were able to drop from a 4-ton to a 3-ton AC when it was time to replace (because the cooling load was that much lower). Not everyone will see that dramatic a change, but even if your AC size stays the same, it will cycle on/off less often (or run at lower capacity if you have a variable system), which can prolong its life. So windows are part of the whole-house system that can save you money in multiple ways.
Just wanted to throw that out there – your AC will thank you for keeping the hot sun out and the cool air in!
Minor thing I noticed after installing my Low-E windows: from the outside, the glass has a bit of a reflective look (like a slight mirror effect when the sun hits it). It doesn't bother me – actually looks kind of cool and modern – but it was something I didn't anticipate. From the inside, I do see a slight tint but it's really very subtle (like a faint green or blue tint depending on the coating). Within a week I stopped noticing it. Colors of the view outside are essentially the same, maybe just a tad "cooler" in tone. As others said, the trade-off in reduced heat is 100% worth it.
Just mentioning this so you're not surprised if your windows look a bit different than clear glass. Totally normal for Low-E coatings. My neighbor even joked that my windows looked like "sunglasses" from the street when the sun reflects off them. But hey, sunglasses for your house are a good thing here!
I'll add that upgrading windows is one part of an energy efficiency strategy. In Florida, attic insulation and proper sealing are also crucial. If you haven't checked your attic insulation, do that too – but given our intense sun, windows play a huge role. When I improved my attic insulation and got new windows, the combined effect was amazing. My attic was already R-30, which is decent, but the windows were the weak link. Once both were addressed, my AC run time dropped noticeably. So for anyone planning a whole-home efficiency makeover, tackle both if you can.
(OP) Update: Hey everyone! I wanted to circle back and thank you all again for the incredible advice and to let you know how my window project turned out. We went ahead and pulled the trigger on the replacements!
What we chose: After considering all the input, we went with vinyl, double-pane Low-E windows with argon, Energy Star rated (SHGC ~0.23, U-Factor ~0.27). We did decide to make half of them impact glass (front and sides of the house) and the other half non-impact with our existing shutters (back of the house), as discussed. It turned out to be a good compromise on cost and protection. The windows we got are a well-known brand (the installer sells PGT and Simonton; we went with PGT). We ended up hiring Pro Tech Windows & Doors after all – User12, your review helped reassure us. They did a fantastic job from start to finish. (Károly was our second choice; they were great too, but scheduling was a bit further out, and Pro Tech gave a slightly better price for the same specs. Honestly, can't go wrong either way as both had great reps.)
Installation: The crew was super professional. They pulled permits, the inspector came as User19 described (checked the screws and labels). They used foam and caulk everywhere. It took two days to do all our windows and one sliding door. Immediately we noticed how quiet the house got once the new windows were in – even before the foam and trim were done, it was like the outside noise just vanished!
Results: It's only been a month, but the comfort difference is HUGE. We had a hot week recently and normally I'd dread the afternoon in our living room – but with the new windows, it was actually pleasant. No more feeling the radiant heat when you stand by the window. Our AC still runs (Florida gonna Florida), but it definitely cycles off more often. I checked our energy usage and compared it to last year’s same month: we used about 18% less kWh! That's in line with what many of you experienced. I'm expecting similar or better savings in the peak of summer.
Also, as User14 said, we noticed our curtains aren't getting that sun-bleached look anymore, and the houseplants are thriving with the gentler light. The slight reflective tint on the outside (User22 mentioned) is actually kind of nice – our house has a cleaner look with the new windows and the neighbors even asked about them.
No condensation issues to report – except exactly what was said: a bit of dew on the outside of a couple windows in the early morning, which I take as a sign they're working.
Final thoughts: This project was absolutely worth it. It wasn't cheap (came out to about $12k total for 15 windows + 1 slider, with the impact glass in the mix), but between the financing we used (0% for 12 months) and the likely tax credit (will claim that $600 back at tax time!), it became manageable. And the difference in our daily comfort and peace of mind (especially going into hurricane season with some impact protection) is priceless.
I can't thank you all enough for the guidance. This thread truly convinced me and informed me to make the right choices. Hopefully, it helps other Tampa Bay folks down the line too. I'm definitely sticking around this forum – what a great community!
[Moderator, feel free to sticky or highlight this thread if you think it will help others.] Thanks again everyone!
This might be slightly off topic, but did any of you have experience with the big national brands vs local Florida brands? For example, companies like Andersen or Renewal by Andersen keep advertising like crazy here – but I also hear a lot about PGT, Simonton, CWS (Custom Window Systems), etc. Are the more expensive national brands worth the premium for energy efficiency, or are Florida-made windows just as good (if not better for our climate)?
Regarding brands: Great question. In my research and quotes, I looked at both national and local brands. My take: the Florida-oriented manufacturers (like PGT, CWS, Simonton (which is national but big in FL), and others like Viwinco, etc.) have products designed for our climate (both the heat and hurricanes). Andersen (and Renewal by Andersen, which uses their Fibrex composite material) make excellent windows too, but they tend to be very pricey. A lot of what you'd pay for is the brand name and the look/finish (Andersen has nice wood interiors and such on some lines, which isn't as big a deal for a block home in Florida where most people go with vinyl or aluminum).
Energy-efficiency-wise, a high-end Andersen double-pane with Low-E will perform similarly in U-factor/SHGC to a high-end vinyl window from PGT or Simonton with Low-E. I actually saw NFRC stickers for both: one of my neighbors got Renewal by Andersen, and their SHGC was around 0.29, U-factor 0.30. My vinyl windows (local brand) were SHGC 0.25, U-factor 0.28 – slightly better actually. So you're not getting some magical efficiency jump with the expensive brands.
What you might get is aesthetics (Andersen has thinner frames on some series, nice hardware, etc.) and maybe a longer warranty or service package. But honestly, the local brands also offer lifetime warranties on vinyl frames and 20-30 years on glass seals typically.
Unless you have a specific architectural look you're going for (like wood-clad windows), I'd say stick with the reputable Florida manufacturers. They know our code requirements and climate needs well. I went with PGT for example because they are widely used in Florida and have a good rep for service if something goes wrong. And parts availability is easier if something breaks.
So yes, Florida-made windows are just as good on efficiency – and sometimes better suited for our humidity and salt air. Andersen (Renewal) will do a fine job too, but be prepared for a much higher quote. For me, the ROI wasn't there for the fancy name.
That's great news, original poster! Congrats on the new windows and thanks for sharing the outcome. It's really encouraging to hear the concrete numbers and satisfaction. Enjoy the cooler house and lower bills!
(Moderator) This thread is indeed a goldmine of information. I've pinned it to the "Energy-Efficient Window Conversations" subforum. Thank you to everyone who contributed such detailed insights, and to the original poster for updating us on the results!
I've been lurking on this thread since the beginning and just wanted to say thanks to everyone. Learned more here than I did in weeks of Googling on my own. I'm in St. Pete and will be doing my windows next month, feeling much more confident now. Cheers!