Heritage double glazing?

[GrizzlebertGrumbledink]

Hopefully buying a grade II listed building but discovered during the purchase that the current owners installed heritage double glazing in place of the previous single glazing and did not seek listed buildings consent as they claim it is "like for like". Never mind that the like for like thing excludes windows and doors. So we're hoping the vendors will try to get this regularised for us but I know it's not popular with conservation officers. I contacted the conservation dept and they wouldn't comment via email and invited us to pay £200 to discuss with them in a meeting.

Anyone got any experience of this? Any happy stories of double-glazing getting approval? I suspect the way forwards is likely to be expensive and draughty...

For the record I think they've done a really good job of matching what was there before, but of course it doesn't matter what I think. Feeling dejected.

Please be aware that undertaking works to a listed building without getting permission is a criminal offence. If you buy the house, you would be taking on the liability of that- the council could legally make you pay for replacement single glazed windows as owner, even if you didn't do the work yourselves.

Around here you wouldn't get permission. It might be worth the £200 fee- you could end up paying £££££ in the long run.

Yeah I know it's a criminal offence - prisonable in fact. So there's no way we'll proceed until there's a way to sort this out. Just wanted to know whether anyone's ever found that the heritage double glazing is in fact acceptable? I've only heard tales of woe