For context, the house was built in the late 90's and had cheap crappy aliminium single pane glass.
I was keen to see how much difference it made, so I borrowed an infra-red camera from work (high quality FLIR unit) and used it on one of the 40 degree days in Feb.
The new DG window was 35.6 degrees, while one of the old windows in the next room (same external wall) was 39.1 degrees.
We've upgrade the insulation, air-con and have added solar, so keen to replace a few more of the windows.
You do realize this is not a scientific way of measuring the performance of a window in a particular climate zone? And even further from evaluating if it's worth the money.
For isntance, we don't have 40℃ 24 hours- 365 days. Also, you are comparing one of the worse with one of the best, there is a lot in between.
Of course I realise its not a particularly scientific way of measuring the performance of a window hence the word novice being the THIRD word in my post and never suggested otherwise.
I disagree with your reasoning about not having 40 degree days 24x7 - they are exactly the days im trying to make more comfortable.
If you knew it is not scientific then what was the purpose of that fact in this conversation? And BTW, prefixing your post with "novice" doesn't give you the right to share data that you know is not adding value.
You said "I was keen to see how much difference it made" and later "so keen to replace a few more of the windows.". This implies you believe your non-scientific experiment that DG are performing much better than SG units, and in relation to this topic, worth the money. You are sharing this data with others which means you are recommending DG windows. And one reason for it, not necessarily true in your case, is to benefit from other people buying DG units.
First, I said 40℃ 24x365.
Second, NO, in Perth, we do not have continuous 40℃ for 24 hours x 7 days. We do not even have continuous 40℃ for the whole 24 hours. I don't believe we have had a day in Perth when the lowest temperature during the night was 40℃. Even if we did, maybe one in 20 years? If we did, I would love to have this info as a "fun fact" please.
I do realise my responses are upsetting to you but I can not serve the truth sugarcoated. If you don't like been called out, please check your facts first before posting, like the 40℃ thing.. I'm sure you know how to use Google or whatever you prefer?