Ich denke darüber nach, die Fenster rund um das Haus auszutauschen, aber bevor ich fortfahre, möchte ich sicherstellen, dass es wirklich notwendig ist.
Alle Fenster sind aus PVC mit Doppelverglasung, aber ich bin mir immer noch nicht sicher, wie gut sie isolieren.
Ich habe eine Wärmebildkamera und für mich sieht es gar nicht so schlecht aus – bis auf die Terrassentüren.
Gibt es einen Energieexperten, den ich anrufen kann, um dies zu überprüfen und mir zu sagen, was ich ersetzen muss?
https://www.reddit.com/gallery/1qr1v5c
Von OldsMan_
18 Kommentare
How does your image compare to newly built houses? Because from this image I would say your windows aren’t very good.
I know nothing about this, but I also have a thermal imaging camera.
Why is my cat pooping at 42.9°C?
https://preview.redd.it/nzo9kkhltggg1.jpeg?width=999&format=pjpg&auto=webp&s=f430f53befaea79038de5bf49273d8a781fbdd74
Do you have a heatmap example to compare with ?
You should try Linux
find out the insulation value for your current windows, you should be able to determine it from the inscriptions on the inside. Compare that to new windows.
Also take things like comfort and sound insulation into account when making your decision to install new windows.
Some cities have a free or cheap energy consulting service.
The heat loss does not look too bad, looks normal for good windows. Better quality windows will cost you around 10k to replace (without the bigger ones – considering any at the back of the house). I estimate roughly that you will save around 25 euro per month in heating costs, or 300 euro per year.
From a financial point of view new windows are pretty slow to earn back in energy savings. Especially if your current ones are half-decent. Not talking about comfort of course.
So i guess the question is: do you have high energy costs and might there be other priorities in terms of insulation?
After moving to our own place I understood why many keeping windows shutters down almost all time in winter.
Well, once it is insane hot, again. This is why it is smart to have shutters white.
And not smart not having, not using shutters.
Would be a couple of years before the energy savings match up with the cost of your FLIR camera so I hope you didn’t buy it for this purpose.
You can find the answer to your question very easily.
Start by checking the inside edge of one of your windows. You will find a label with a series of letters and numbers.
Search the Internet for the manufacturer and model of the glazing using the information you have found.
If you can’t find it straight away, you can ask the manufacturer for the Ug value of the glass (the heat transfer coefficient) using the internal manufacturing code.
1.1 is already very good. The lower the value, the better.
Above 1.4, it’s a good idea to change. Current triple glazing is around 0.7.
Just a tip: if your glass has condensation inside the pane you can get a repair quote and claim on your house insurance. I used the money to replace them. Got a few grand that way as I had some big ones that were done.
I upgraded double from 1998 to triple in 2025 and there is a big difference. No more moisture/condensation on the windows in the morning.
If you do this to have a better EPC rating I would suggest you to focus first on roof insulation or a decent heating system
I also have old double glazing, and recently found out that there are companies who specialise in replacing the glass with better insulated modern double glazing. While keeping the old frames. Way cheaper, so that might be more worth it.
What’s s the return on investment for replacing the windows tho?
-40k for the windows to save 400€ a year on energy ?
Granted the house will go up in value for replacing the windows but I don’t think you will be able to recover the whole 40k from the buyers.
Could you walk the neighborhood and ask a neighbor with brand new windows… do a scan there and compare.
Also… what are your results of an inside scan of those walls / windows? To me, if outside is 0… your window is eight
Inside is 20… your window there is 18, you have a 2° loss, and 10° gap.
If your inside window is 13°… that’s a bit more… but no idea what that would translate to (gas / heat consumption wise)
its not worth it for this amount of surface, it would be worth it if you’d be replacing a veranda but imo you wont even notice the difference
1. Calculate how much do you spend on heating yearly.
2. Estimate you will save 50% (or even 80%) of it by installing new windows.
3. Divide the cost to replace the windows with the savings, giving you the number of years to recuperate the investment.
4. Decide whether it is worth it.
look up the U values of your current windows, it’s printed on the outer edge and should be readable.
Compare this to what you would be getting.
https://preview.redd.it/eqt2eocvchgg1.png?width=900&format=png&auto=webp&s=517a0b1c17fb861b158507f926609e690b05a371
Your heat scan sais nothing 🙂
There is a lot to be improved if you have the oldest forms of double glazing.
„Dubbel glas heeft een isolatiewaarde van **2,8 W/m²K** in vergelijking met 5,8 W/m²K bij enkel glas. Bij hoogrendementsglas bedraagt de U-waarde 0,8 tot 1,1 W/m²K en bij driedubbel glas ligt die tussen 0,4 en 0,8 W/m²K.“
Extra tip: sometimes you can replace the glazing inside the windows without replacing the entire window structure. Much cheaper if possible.