After much lurking I have made an account with an issue of my own, this may be quite a unique problem!
Six months ago we moved into a lovely grade II listed flat (conversion). I think it is generally well converted, bar one big overiding problem in it has a large skylight taking up a third of the ceiling in the kitchen/lounge.
Being biggest feature (best and worst!) it is of course listed and single paned. No windows can be opened (we have an air recovery unit). Windows are in the bedroom/bathroom only anyway.
On moving in it was well over 40 degrees in the property, the builder was forced to install an aircon unit, which more papered over the issue (yet lulled us into thinking it would warm in winter). It clearly needs double glazing to be habitable. In the winter it is now very hard to get above 12-15 degrees even with two radiators (2kw electric, as no gas) and aircon unit on heat all day and bedroom doors shut (as also single pane and not double glazed but rather another layer of single glazing, sliding 20cm apart). Bedroom and bathroom are freezing.
The issue here is I think if retested the EPC would be an F (as it wrongly states we have double glazing) and there is surely no way it is right that we cannot make our flat at least bearable. Another issue is the condensation gets very bad and drips onto our carpet/furniture. We have tried upping the air recovery system (too loud too hear TV/music over), having extractors on (also extremely loud) and using the aircon on dry. To no avail.
The builders have skirted around/ignored the issue so far saying because it's listed they can't alter, they clearly didn't enjoy working on it as they didn't bother cleaning the paint off the windows and it needs a scaffold tower. I was told by one painter it was 50 degrees when he was painting!
I believe there could be a layer of glazing underneath the skylight (flat along ceiling on inside), which would make it airtight and stop it getting too hot/too cold, as well as being allowed on listed building rules. But I am unsure where we stand with it, and what to grounds to press them on if regulation hasn't been met.
I wonder if anyone has any experience with such a matter? Or could offer advice.
We cannot afford to have 7-10kw of heating combined on for even a few hours a day, and certainly not put in double glazing ourselves yet. We didn't get any snagging/additional surveying done.
Thanks kindly