Double V Triple Glazing

[mir2001]

It never ceases to amaze me the amount of pure bs is used by sales people. I wonder who is using some trickery to flog windows in this instance!
That comment about aluclad is bull, I suggest.
The devil is in the detail here so look for and interrogate the certification paperwork on the windows. My advice is if certification detail is not easily forthcoming then keep looking.

Thanks @Micks'r - it’s been suggested to me that the value of 0.8 is the glass alone while the higher value is for the entire frame - so the discrepancy is due to more transparent companies giving you the value for the entire frame.

 

[mir2001]

Thanks @Micks'r - it’s been suggested to me that the value of 0.8 is the glass alone while the higher value is for the entire frame - so the discrepancy is due to more transparent companies giving you the value for the entire frame.

Just a quick update to say I found two other companies that could supply window frames with overall u values of 0.8 in casement windows and 0.9 in tilt and turn. In the case of both companies, the TG windows were 44 mm instead of the 40mm offered by the company who said it wasn’t possible to get those value with a uPvc frame. So it would seem @Micks'r was right about the aluclad comment being nonsense. I now have two companies who are using the same glass company for manufacture and the same window frame brand so I guess it’s down to who will install best. One (rough) quote is circa 4K less than the other. Both have good online reviews. One is more established and bigger. Cheaper one is possibly a two person team.

 

[Horatio]

I would assume that the company fitting the windows would only recommend/offer TG if the frames support it, as such.

I think that assumption Is flawed with respect to the earlier cold bridging comment. I'd expect a window salesman to recommend his most expensive offering.