A quick note on aesthetics and options: When you get new windows, you often can choose different styles or add-ons that your original windows might not have had. For example, I opted to add internal grids (grilles) in the top sash of my front-facing windows to give a kind of colonial look to the house. It makes the front of the house look more classic, which I love, and since the grids are sealed between the glass, they don’t hinder cleaning or anything. The back windows we left without grids for an unobstructed view of the backyard. It’s the best of both worlds.
Also, consider the tint level of the Low-E coating. Some Low-E glass has a very slight tint (either a bit greenish or blueish) when you look from outside, and a slight mirror effect. We were worried our house might end up looking like a commercial building with reflective glass, but it turned out absolutely fine. You can hardly tell any difference in appearance unless you really stare at it. From inside, the clarity is great – colors look true. Maybe just marginally less blindingly bright sun, which is a good thing. At night, the windows are clearer (old ones had a haze from condensation between panes).
Oh, and if you have any specialty windows (half-round arches, etc.), replacing those can really freshen up the look because over time the glass can dull or the frame discolors. We had a decorative arch window that got replaced and the new glass is so much clearer. Little things like that add up to an overall nicer home appearance, not just efficiency.
I want to provide a realistic expectation from my experience: the energy savings can be modest depending on your starting point. My home was built in 2013, so the windows were actually not terrible to begin with (double-pane, metal frame with some basic coating, I think). We decided to upgrade in 2022 mainly because a few had issues (one cracked, some seals failed) and we wanted to improve soundproofing. We spent about $7,500 on 10 windows (non-impact, high-efficiency vinyl replacements). After all is said and done, our electric bill only went down by maybe $15 a month on average. Not huge. That’s roughly a 10% decrease for us. So from a pure money-saving perspective, it’s going to take a very long time to pay off via energy bills. We knew that going in, though, because our existing windows weren’t horrendous.
However, we did notice improvements in other areas that made it worthwhile for us:
Comfort: As everyone says, the rooms are more uniformly cool. No draftiness, no hot spots. It’s the difference between “the AC is technically keeping up” versus “the AC easily keeps up and shuts off more often because the house stays cool.”
Noise: Big change. We don’t hear the neighbor’s music or cars on the street as much. It’s more peaceful.
Condensation and drafts: Gone. We used to see a little moisture or feel slight warm air near some windows – that’s history.
Looks: The new windows just look sharper. The old ones had dingy frames and one had condensation stains that we couldn’t clean. Now everything looks new and clean.
So I would advise: if someone’s expecting their $7k-$15k window project to slash their $200 electric bill in half, that’s not going to happen in a modern (under 20-year-old) house. You’ll see improvements, but not miraculous ones. The value is in incremental savings plus all the non-monetary benefits. For us, it was still worth it. We kind of treated it like a home improvement/quality of life upgrade, not just an energy upgrade. As long as you go in with eyes open on that, you won’t be disappointed.
Good points @drummer573106. In fact, I’ll share that I actually decided NOT to replace my windows yet in our 2015-built home. Instead, I invested in other energy improvements first. Our windows are decent double-pane vinyl already (they have a basic Low-E). My energy audit indicated more loss from the attic and ducts than from windows. So I spent money on sealing duct leaks, adding attic insulation, and upgrading to a more efficient HVAC. Those changes gave me a pretty immediate reduction in bills (my usage dropped like 20% from those).
Now, do I still want to replace windows eventually? Yes, for many of the comfort and noise reasons discussed. And because I know even a 2015 double-pane window isn’t as good as a 2025 one in terms of tech (maybe our current windows have U-factor ~0.5, SHGC 0.4, whereas new ones can be U0.28, SHGC ~0.25 which is a lot better). But I’m prioritizing other projects first since our current windows aren’t failing or anything yet.
I guess my point is, for anyone reading, evaluate your current windows’ condition and performance. If a house is under 10-15 years old and had at least mid-grade windows installed, the urgency might be lower than a 20+ year old home with builder grade or failing windows. Eventually, I’ll do it for the reasons of long-term efficiency and getting those nice new features, but doing it at year 8 of the house’s life felt too soon for me. I did minor things like caulk tiny gaps and ensure weatherstrips are good in the meantime.
This isn’t to deter anyone – just sharing another perspective that in some cases, window replacement is the cherry on top after tackling other low-hanging fruit. In older homes or ones with clear window problems, it’s a no-brainer first step, though.
@robertblogger makes a fair point – it’s all situational. In our community, most homes were built around 2005-2010 and many of us are reaching that point of considering window replacements. Some neighbors have done it and swear by it, others are holding off because their windows are “good enough” for now. I think this thread has captured the key considerations really well.
From everything everyone’s said, some quick takeaways I’ve gathered:
If your house is ~15-20 years old, your existing windows are likely middling in performance now (tech has improved, and they might have degraded a bit). Replacing them will give moderate energy savings and noticeable comfort gains.
If your windows are damaged (foggy, leaking, hard to open/close), replacement is almost certainly worth it just for maintenance reasons, and energy savings will come as a bonus.
If you do replace, choose a good installer and don’t skimp on the features that matter (Low-E coating for sure in Florida, and argon fill which most double-panes have by default).
Impact glass is a worthwhile consideration in FL for safety and insurance reasons, but you can mix with shutters if needed to control cost.
ROI purely on energy $ is long, but factoring in comfort, reduced noise, and some add to home value, it’s a more well-rounded ROI.
Everyone who did it seems to enjoy their home more afterward (that’s a big quality of life thing).
I’m personally convinced that when my windows hit the 15-year mark (in a couple more years), I’ll proactively replace them. This thread has armed me with knowledge, so huge thanks to all contributors.
I wanted to touch on the installation process a bit more, as someone who’s fairly handy and watched the whole thing like a hawk during my project. One thing I’ll emphasize (which was mentioned earlier) is proper insulation and sealing. When the old windows came out of my house (built 2010), I was surprised to see there were gaps around the frames with basically just air – the builder had not insulated around the window, just stuck the window in and covered it with trim. The installer of my new windows (this was ProTech Windoors, who I found thanks to some recommendations) used fiberglass insulation and low-expansion spray foam in those gaps before installing the interior trim. That ensures no drafts. Then they caulked both inside and outside. This is the kind of detail that separates a good install from a mediocre one.
Additionally, they shimmed and leveled each window correctly so they operate smoothly. I have a friend who had windows done by a sketchy contractor (cheaper bid) and some of her windows are tough to open because they weren’t perfectly squared in the opening. That can also affect how well they seal. So again, installer quality matters a lot. Ask questions about how they install – do they use foam, do they guarantee easy operation, etc. The good ones will happily explain their process.
After seeing it done right, I’m very satisfied that my windows will perform as advertised. The house feels snug. No wind noise on breezy days like I used to have (I’d sometimes hear a faint whistling with old ones – that’s gone). So ensure whoever you hire pays attention to these details.
Quick question for those who did windows: did you also replace sliding glass doors (if you have them)? I have two sets of old sliders to my patio that are single-pane and very drafty. I figure if I do windows, I should do the sliders too for the full effect. But I’ve heard sliding doors can be really expensive to replace. Is it worth doing those as well? Did you see efficiency gains from new patio doors? My concern is that a lot of heat comes through those big glass doors and they’re not very secure either (just a simple latch that feels flimsy). I’m considering upgrading to maybe impact glass sliders for hurricane/security benefits plus efficiency. Any thoughts or experiences with replacing patio doors along with windows?
@markbaker838 – Yes, we replaced a big sliding glass door at the same time as our windows. Absolutely include it if you can budget it. Our old slider was original from 2002, aluminum frame, single-pane – basically the weakest link in the house’s envelope. You could stand next to it in summer and feel the heat radiating, and in winter feel the chill. Plus it would leak a bit of water during wind-driven rains (not to mention the lock was wobbly as you said).
We put in a new vinyl framed slider with double-pane, tempered Low-E glass (we opted for impact glass for this door because it’s a large opening). The difference is night and day. No more drafts at all – when it’s closed, you don’t feel any temperature difference near the door. The glass is heavier and better sealed, so no water leaks in heavy rainstorms so far. The door came with a multi-point locking mechanism which feels a lot more secure than the old single latch. And of course, it’s way more energy efficient – it’s basically like having a giant energy-efficient window. Our installer mentioned that a lot of people overlook the impact of a big sliding door on their cooling costs; it can be as much glass area as several windows combined. So upgrading it yields significant benefit.
It was expensive – I think we paid around $3,500 for that 8-foot impact slider (that’s part of the $12k total I mentioned earlier for our whole project). But given it’s functioning as both a window and a door and a hurricane barrier, I found it worth it. Even if someone couldn’t afford to do all windows, I’d almost say do the slider and the most sun-exposed windows first, because those made the biggest difference.
In summary: if you have drafty old sliders, definitely plan to replace them as part of the project. You won’t regret it.
I’ll second what @cooking518 said about sliders. We changed our old patio door, and it was a big relief. One tip: after getting a new sliding door, ensure the installer properly seals the bottom track and any gaps around it. Ours initially had a small air leak at the bottom because the caulking wasn’t perfect. I noticed a tiny bit of light coming through in a bottom corner when the sun was shining just right. I pointed it out and they quickly fixed it with additional sealant. Now it’s airtight.
Also, new sliders often have Low-E glass just like windows, so you’ll notice the same effect of less radiant heat. Before, when the sun hit our old slider, the tile floor near it would get hot. Now it stays much cooler. So yes, treat the glass door as part of the window system upgrade. A lot of builders in the early 2000s didn’t put in great patio doors in terms of efficiency. Replacing it can eliminate what might be the biggest source of heat gain in your whole house.
(Original Poster here) Good to know about the sliders! I do have one large 3-panel sliding door to my backyard. It’s also builder grade from 2008 and not in great shape. Sounds like I should include that in the project for sure, otherwise it’ll be a weak spot. I hadn’t even thought about how much area that door is – probably equivalent to like 3 or 4 windows worth of glass.
Also appreciate the discussion on installation details. I will make sure to ask the companies about foam insulating and all that. I want this done right. The last thing I want is to pay all that money and still have drafts due to sloppy installation.
This thread has grown so much – thanks everyone! It’s almost like a community brain dump of knowledge now, which is awesome.
Jumping in a bit late, but I wanted to add a pro-tip about insulation around the window (since @dwhite46 and others touched on it). If you have access to any of the window frame from the attic or crawl spaces, check those areas after installation. In my house, when I replaced a few windows, I peeked in the attic area above a window and noticed that while the installer foamed around the immediate perimeter, there was a bigger gap in the framing of the house that was just open (not visible from the room side, only from attic). I ended up stuffing a bit of fiberglass batt in there to be sure it was insulated. This might be overkill, but every little bit helps with efficiency.
Most people will never need to do this, especially if the installers did a thorough job. But if you’re the curious DIY type, it doesn’t hurt to double-check any accessible spots. I’d say 99% of air leakage will be handled by a proper install, but I’m a perfectionist 😅. After I did my little extra insulating, I sealed the attic opening back up and called it a day. My house is super tight now.
Since doing the windows, I also noticed the HVAC cycles on less frequently, indicating the house is holding its temp better. The difference was not just windows of course (I did some other air sealing as well), but windows were the major project.