This may be a bit of a re-run of some past posts on here, but wondering if things may have changed since the last time this was discussed: What are some good options for reducing the thermal bridging around openable rooflights like a Velux?

We have plans to include two fairly small openable rooflights - looking at Velux or Fakro - in our loft conversion. Have scoured for guidance on how to minimise the bridging around the frames but it seems little has moved on since this post from over a decade ago, and the manufacturers still offer fairly limited solutions in this space:

http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4112&page=1" >

Some specific questions:

1) One of the interesting ideas I've seen mentioned in a few previous posts is about constructing some kind of mini-SIP to house the Velux frame in. Has anyone got any pictures or links to anything detailing how this has been done successfully?

2) I'm planning on putting 80mm PIR above the rafters; can't find guidance on how to install Velux or Fakro in such a circumstance - presumably they have to be installed onto timber, not to PIR - so would we need to construct a raised timber frame above the rafters in line with the insulation, to secure the frame into? If so, then I guess that's introducing more thermal bridging - any ways to mitigate this? I've seen mention of wrapping Aerogel up the insides. Worth it?

2) Should we rethink having openable rooflights? The loft design has one rooflight in the bathroom, one in the bedroom, and then a large openable window on the dormer side. We're due to have MVHR. Do we need to be able to open the skylights, or should we consider being more radical and having them fixed to improve the overall thermal performance?). Feel like we will want cross-ventilation on warm summer nights... Obviously this is a personal choice kinda question but I'm curious what the folks on this forum would do.

Thanks

thanks djh