Roof Lantern install issue

[MiloD]

Hi all,
Hoping for help on a recently installed roof lantern problem. Since the drop in temperatures the room is freezing, reported this to the installer and after much prodding he advised he'd found a 5p sized gap in a corner and sealed it. Having been up and looked it seems sealant has now been applied to all the corner joints which it's now clear had previously been left with gaps where the beams from the top with a shallow V profile meet the plinth, poor explanation I know. There was nothing creating a seal. Now just blobs of silicone, may I get your thoughts before I go back to him please?

Have attached pictures which will hopefully show what's been done.

Thanks in advance.
Milo

 

[crank39]

Thats just poor, every picture shows gaps and sealing up appears to have been an after thought, silicone applied looks as though it was done in a rush just to say they've done something and to get you off their backs, at the bare minimum I'd say all the glass has to be stripped out to seal the gaps including sealing the frame to the lead upstand

 

[foxhole]

Even installed correctly an uninsulated “hole” in a roof is not going to keep heat in.

 

[MiloD]

Thanks both. Crank39, the sealent was a rushed afterthought as you say. Should the gaps be filled both from the inside and externally when the glass is removed? Given what's been done so far anything else I need to watch for when requesting the install is corrected?
I'd been assured that insulation was put into the inside of the upstand behind the plasterboard.