Can i use second hand french doors.

[amazondean]

I am having my dining room extended soon and was wandering if i can use second hand french doors. I realise the glass will have to be toughened but new builds have to have special thermal qualities i am aware.
Will the inspectors check to see if the glass has this "U" value or will they just check the stamp on the glass for toughened glass. I have got my eye on some used byfold hardwood doors as well as some french doors with sidelights. I am loathed to buy new when there are very good second hand units out there but most will only be toughened and not up to the more modern units
My extension is small enough to qualify for it to be built under building notice if this makes any difference.
Your advice will be most welcome.

 

[jono_h]

Dean,

Practically there won't be a problem - I have used a second hand set in my extension. However I haven't yet had it signed off.

That said I know my BCO from my last house, and I'm sure there won't be a problem. Last time he just looked for the kite marks and was happy.

I'm happy to be proven wrong, but I would have thought that the difference in insulation performance between a second hand set of doors and new - over the the area in question - would be minimal.

 

[noseall]

The units could be replaced for toughened low 'e' fellas and i guess trickle vents could be fitted if necessary.

 

[amazondean]

That sounds good. Regarding the trickle vent, i have had to have a vent cut into the wall when i had cavity wall insulation fitted because i have an open fire., so i presume i will need to do the same on the extension which means i shouldn't need trickle vents in the doors. Is this the case. Or could i have trickle vents on the doors and do away with the vent in the brick work!!