Aside from other things going on, chez P is currently having an extension built!
It seems the building inspector has flagged up that we’re looking at ‘overglazing’ the extension. Hmm…
I appreciate the basic calc is that we can have (the current glass area the extension is replacing) PLUS (25% of the new floor area in M2) as glass.
However, in order to allow MORE glass in the extension, we can take into account U-values.. i.e newer/better glass can have a U value of 1.0.
My question is: “what is the basic/standar U-value the Building inspector classes glass to be (double glazed)?”
I.e if they assume standard glass is the MINIMUM of 2.0, then a u value of 1.0 means we can have twice as much, no?
Also, one of the windows we are removing (for the extension) is single glazed. I believe the U-value of this is 4.8, right?
Cheers!!
DrP