When a large area of drywall is really hot, there is a reason why.
One thing I do during a home inspection is sweep the house with a thermal camera.
And Mighty Mo is good at what he does.
This is the back side of a skylight over the master bathtub.
While standing in the tub and looking up this is what the drywall looked like.
Not a really hot day, 83F, the back wall (and one side wall) of the drywall was pretty hot.
This means that in winter it is pretty cold!
They why is pretty obvious.
Whenever drywall is unusually hot or cold it is always insulation related.
Viewing that same skylight from the attic space the reason for the heat was obvious.
The spot is devoid of insulation.
Ideally that spot would be insulated with a thick bat insulation, R-30 or so, with the paper vapor retarder touching the drywall. Then that cottony fiberglass insulation would be blown in on top to seal any bypasses.
I expect in winter sitting in that tub would be uncomfortable!
My recommendation: some things are best learned by a home inspector. And other things are better learned by a home inspector with a thermal camera. How many homeowners venture into their attics to just check things out? For how many years did these homeowners wonder why the bathroom was so uncomfortable!? Now they know why. And they can make it right for somebody else!
Jay Markanich Real Estate Inspections, LLC
Based in Bristow, serving all of Northern Virginia.
Office (703) 330-6388 Cell (703) 585-7560