craig

It depends where you are sourcing your products, alu spacers are still fairly common unfortunately. Regarding timber beating uPVC, a good quality uPVC frame with 4/5 chambers will beat a timber aluminium window on performance. They will have testing done on the system or at least they will be using the tested performance of the profile from the supplier. The program they use (excel, winpro etc) will perform the relevant calculation and supply the Uw, some won't even display it and just say AA Rated for example. From recollection, the lambda (λ) are pretty similar across the relevant timbers With oak being slightly higher.

Of course, you are correct but I was talking specifically about glazing on the assumption of a good frame but never qualified that point.

That's not really correct. Triple glazing isn't primarily about reducing outside noise, its main advantage is improved thermal performance. A typical modern double-glazed unit might have a Ug-value around 1.0–1.2 W/m²K, whereas a good triple-glazed unit can be around 0.5–0.7 W/m²K, so the heat loss through the glazing itself can be roughly 40–50% lower. That doesn't mean your heating bill drops by 40–50%, because windows are only one part of the building's overall heat loss. Interestingly, triple glazing isn't automatically better acoustically either. For noise reduction, the thickness and combination of the panes, cavity widths and especially acoustic laminated glass can be much more important. A properly specified acoustic double-glazed unit can outperform a standard triple-glazed unit. So there are perfectly valid arguments about whether the additional cost of triple glazing is worthwhile for a particular property, but saying the thermal difference is minimal and triple glazing is mainly for noise isn't really accurate.

Double glazing at 1.2Ug, isn’t bad at all but expected Ug now for double glazed. I can only suggest getting a system that can handle the weight.

Factory glued but also done on site when required, as sometimes you need to fix through the frame and glass needs to be supplied loose.

What do I use when it's a cost thing? Aluplast Ideal 4000 (Double) Aluplast Idea 8000 (Triple) Alternatively I would look at Rehau, Gealan or Salamander.

Very easy to replace, obviously not as easy as glass into the frame without glue but it's a security thing as well. Doesn't take much longer to remove the glue, clean and put new unit in with the glue. It's also an extra, not standard.

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The amount of chambers, welds, material used (polybutylene terephthalate (PBT) engineering plastics rather than steel for strengthening and thermal improvements

It definitely is, we still come across windows fitted horrendously, newspapers stuffed in for insulation.

For me, Aluplast, specifically the Energeto 8000. Is it the cheapest? No.

This is an upgrade? It should be🤬 standard, that's why I assumed it was foam injection for the Energeto 8000

Yes, just trim it back, will make your life easier. Without knowing the product supplied, I can't really say what the values are as I would be guessing but in principle, if triple and insulated frame (foam injected into the frame), you're probably looking at the Energeto 8000.

Foam just needs tidied up and then plaster, also aluplast, well done. 4000, 8000 or Energeto? Did you purchase from a UK supplier?

You should be able to take measurements internally/externally in the same fashion. That diagram is perfect. The internal measurements compared to external will be different and depends on finishes, they could be the same but if brick to brick externally, then I’d expect internal to be slightly smaller as the window measurement will be reduced by the plasterboard (if it is not sitting behind the ingo/check reveal). I doubt it is a check reveal if you’re in England.