Double or triple glazing in new buildings - triple glazing allegedly unnecessary expense

Ok, ok there was certainly some confusion with the Uw or Ug values, sorry about that.

That's no problem. That's why you're here, to get information.

I deliberately wrote the level of KFW60 because the energy consumption of the house is exactly at this level.

KfW 60 will no longer be approved next year. So you can't build at this level either and must – if possible – spend the savings elsewhere, for example on the windows. Aside from that, double glazing for a new build is roughly like an old gasoline engine from the 90s. No longer state of the art. I would never think of using such windows (even if they might work theoretically) in a new build.

On the contrary: I was actually fully convinced to take the triple glazing, the advisor himself then said on his own that it actually doesn't make much difference overall. I was then very surprised myself.

It really doesn't bring much – KFW 55 is and remains KFW 55. Then you just lose more energy through the windows and less through the facade. But with the windows, especially if they are large elements, you feel the cold that comes through.

KfW 60 has never existed.

Strange, I live in one. Is it like with Bielefeld? :D

Strange, I live in one. Is it like with Bielefeld? :D

Maybe I should have said: It hasn't existed for over 10 years ;)

Here are a few more details.

Double glazing: Glass has Ug 1.1 --> Uf = 1.20
Triple glazing: Glass has Ug 0.6 --> Uf = 0.89

Thanks so much in advance for the quick feedback!

PS: Do these Swissspacers make sense? They further reduce the Uf values by about 0.02 each.

PPS: The building application was submitted this year, so still according to moderate energy saving ordinance conditions aka KFW70 as minimum spec. ;-)

I consider the idea of double glazing (in the south) (and thereby possibly making sliding doors easier) to be quite reasonable; this would have to be considered on a case-by-case basis.

Apart from that, double glazing for a new building is roughly like an old gasoline engine from the 90s. No longer state of the art.

I see it differently, see also "Are three window panes better than two?" (not linkable here, but easy to google with quotation marks), I also recommend the related article on the topic "warm edge," in which ...

Swissspacer

... however, are not yet mentioned. The term is probably also a registered trademark – how far the concept is patented, I have not yet researched. But I do not see it as a fundamentally new reinvention of the wheel.

Here are a few more details.

Double glazing: glass has Ug 1.1 --> Uf = 1.20
Triple glazing: glass has Ug 0.6 --> Uf = 0.89

Thanks very much for the quick feedback!

PS: Do these Swisspacer make sense? They reduce the Uf values by about 0.02 each.

PPS: Building application was submitted this year, therefore still moderate Energy Saving Ordinance conditions aka KFW70 as minimum spec. ;-)

Here is your answer. Especially with larger surfaces, the glass makes up a larger percentage than the frame. Use triple glazing.