Energy Efficiency Results After Window Replacement in Tampa Bay

We live in St. Petersburg in a 1960s block home, and we had those old jalousie windows (the crank-out glass slats) on our back porch plus single-pane aluminum windows throughout the house. We finally bit the bullet and got them all replaced through Karoly Windows & Doors, and I’m honestly kicking myself for not doing it sooner.

The house is so much easier to keep cool now. In the July heat, our HVAC used to struggle nonstop, but after the window replacement it actually cycles off periodically because the cool air isn’t leaking out and the heat isn’t pouring in. We noticed roughly a 15% drop in our electricity usage the month after installation – a pleasant surprise. Plus, our back porch (Florida room) with the new windows is now usable living space; it stays about the same temperature as the rest of the house, whereas before it was an oven in summer. Big thanks to the Karoly team for the knowledgeable guidance on selecting Low-E, argon-filled double panes for our project. It definitely paid off in comfort and energy savings.

I’m in Clearwater in a two-story townhome and replaced my builder-grade windows with mid-range double-pane vinyl windows. My previous windows were actually double-pane but had no Low-E coating (just clear glass), so I didn’t expect a dramatic change. Indeed, the energy savings have been moderate but noticeable – my electric bill is down maybe 8-10% in peak summer months. What I do feel is that the indoor temperature is more stable room-to-room. Before, the upstairs bedrooms were always hotter than downstairs, especially in the afternoon. Now, after replacing the windows upstairs and down, the temperature difference is much smaller. The AC runs a bit less frequently to keep the whole place comfortable. I also noticed the new vinyl frames don’t get nearly as hot to the touch as the old aluminum frames did under direct sun. It’s not a night-and-day difference like some older homes might see, but I’m glad I did it – every bit of efficiency helps, and the comfort improvement upstairs is worth it.

I live out in Brandon in a 2005-built home. It came with cheap builder-grade single-hung windows – they were double-pane but not Energy Star rated (no Low-E or gas fill). We replaced them last spring with high-efficiency double-pane windows (Low-E coatings and argon gas fill). The impact on our energy use was noticeable but not huge, probably because we already had double panes to begin with. I’d estimate maybe around a 10% reduction in our summer cooling costs. However, the biggest thing we noticed is better indoor temperature regulation. The back of our house faces west and used to get absolutely blasted by the sun; by late afternoon those rooms were 5+°F warmer than the rest of the house. After the window upgrade, those rooms stay much closer to the rest of the house’s temperature – no more feeling like a sauna at 5 PM. The AC keeps up without issues even on 95°F days now. Another benefit: we don’t feel as much heat radiating off the glass. Previously you could literally feel the heat standing near our sliding door; now it’s comfortable to sit right by it. So while the percentage savings on the bill aren’t massive, the comfort difference is significant. It feels like a more upscale home now in terms of climate control.

I’m in Palm Harbor and had Pro Tech Windows & Doors replace my old single-pane windows with new double-pane, impact-rated windows (with Low-E glass). The difference has been phenomenal.

Our house is block construction from the 1970s, and before, it was an uphill battle keeping it cool in the summer afternoons. Pro Tech recommended a slightly tinted Low-E glass for the west-facing side of our house to cut down on the brutal late-day sun, and that was a smart call. Now those west-facing rooms stay much cooler and our AC isn’t kicking on nearly as often at that time of day. We saw about a 20% drop in our August electric bill compared to last year, which is more than I expected. The humidity inside also seems easier to control – probably because less hot air is sneaking in. I also love that these new windows are impact rated (hurricane-safe), which gives peace of mind for storms, and as a bonus, they’ve noticeably improved the sound insulation. All in all, going with Pro Tech and investing in good quality windows has made our home more efficient, comfortable, and secure.

Our home in South Tampa is a 1925 bungalow that still had the original old wood single-pane windows in most rooms (with some storm windows added). They were charming but horribly inefficient. We finally replaced them with custom double-pane, Low-E vinyl windows (we kept the historic look by adding grids). The difference in energy efficiency was obvious immediately. Previously, even with the AC running, you could feel the heat radiating through those old windows in summer and feel a slight warm draft near them. Now, with the new windows, there’s no heat coming through – you can stand by the window at midday and not feel like you’re next to an oven. Our AC run-time has gone down considerably; it doesn’t turn on as early in the day as it used to and cycles off more often. I don’t have exact numbers but our electric usage definitely went down – maybe on the order of 10-15% reduction during the summer months, judging by our bills. Also, this past winter (what little winter we get in Florida), we noticed fewer cold drafts at night. The house holds heat better on those occasional chilly nights, so we hardly used our space heater at all. The improved comfort is huge for such an old house, and we retained the classic look, so we’re very happy.

I have a 1980s ranch-style house in Largo, and I replaced my old aluminum-frame windows with new energy-efficient vinyl ones. One thing I noticed – aside from the lower electric bill (down by about 12% on average) – is how much quieter the house is now. It’s not something I originally thought about, but the new double-pane windows block a lot of outside noise. I no longer hear the neighbor’s loud music or lawn mower as clearly as before. In terms of cooling, before the change, certain rooms (like the one with a big bay window) would get really hot in the afternoon sun. I often had to crank down the AC just to keep that room bearable, which in turn made other rooms too cold. Now, after the window replacement, that bay window room stays at a consistent temperature with the rest of the house. I don’t have to fiddle with the thermostat constantly anymore. The climate throughout the home is more balanced and the AC doesn’t run itself ragged trying to compensate for hot zones. So for me it’s been great: lower bills, more even temperatures, and a quieter home environment to boot.

@tigger_river I had a very similar situation. My house in Westchase (Tampa area) was built in the early 2000s with basic clear double-pane windows. We upgraded to Low-E argon-filled windows last year. Like you, we didn’t see a massive drop in the electric bill – ours came out to around a 10% savings in dollars. But the comfort difference, especially on the side of the house facing the sun, is definitely there. Before, the heat would just pour in through that glass. We even tried adding reflective window film at one point to those windows, which helped a tiny bit but not enough. After the new windows with proper Low-E coatings, the heat gain through the glass is so much lower. Now you can be in those formerly hot rooms at 4 PM without feeling miserable. And as a bonus, the new windows don’t sweat with condensation in the humid months like our old aluminum frames sometimes did. So while the payoff in money saved might take a while, it absolutely made the home more comfortable and solved some nuisance issues like condensation and hot spots.

Our home in Dunedin was built in the 1950s and had a mix of old single-pane windows and some jalousie windows on the sun porch. We replaced every last one of them with modern double-pane windows. We actually used Karoly Windows & Doors for the project after hearing good things, and they lived up to their reputation.

They helped us choose vinyl frames and Low-E2 glass to maximize efficiency. The result? Our home is noticeably cooler and less humid inside. I’d say the summer electric bills dropped by around 15% on average, but even more importantly, the house just feels less stuffy. Before, on humid days, the old leaky windows would let in moisture and our indoor humidity would creep up, making it uncomfortable even at the same temperature. Now the indoor air feels drier and our AC doesn’t have to work as hard to dehumidify. Another thing: the new vinyl frames have made a difference – our old aluminum frames used to feel hot to the touch and even caused the areas around the windows to warm up. With vinyl, that conductive heat is gone. We also noticed no more fading of our curtains and furniture near the windows, since the Low-E glass blocks a lot of the UV. All in all, a huge improvement in our daily living environment. The energy savings are nice, but the comfort upgrade was beyond what we expected.

I’m over in Valrico and replaced my windows about a year ago. I’ve been monitoring my energy bills closely. I have a 1990s-era home that had the original single-pane aluminum frame windows. After installing new double-pane Low-E windows (and a new sliding glass door as well), my cooling costs went down significantly – roughly $30-35 less per month during the summer, which for me was about a 15-18% reduction in my bill. That was actually a bit better than I expected. I figured I’d get some savings, but seeing it add up month after month has been great. I keep a spreadsheet of my energy usage (yeah I’m that guy), and you can see the clear drop starting the month after installation.

Beyond the numbers, the comfort is the big win. My wife and I immediately noticed that rooms which used to warm up in the afternoon sun now stay comfortable. We used to have to run a ceiling fan on high and lower the thermostat to 72°F to keep the living room comfortable at 3 PM; now we can leave it at 75°F and it still feels fine. So we’re not only using less electricity, we’re more comfortable with a higher thermostat setting than before. The investment was definitely worth it for us in multiple ways.