New to the TT world

ChrispyjCSLT22 wrote:

block foam insulation, roof insulation, have they not improved? especially on these new rigs?

No.

Just because they use "block foam" doesn't mean they have been "improved".

Typical block foam is the same stuff used for you foam coffee cups to keep you from burning your hands while holding the cup know as expanded polystyrene. The R value of it is very low per inch, about R3.6-R4. It is used as a cheaper alternative to fiberglass or other higher R value foams.

It takes a lot of block foam thickness to get a decent R value and RVs only have 1 and 1/4" of wall thickness to work with..

The roof is not all that much better as it is not flat, it is higher in the center and lower on the edges to shed water.. Typically the center of the roof is only 2" and the ends taper to about 3/4". The exception to the 2" is RVs with ducted A/C as they need a bit more clearance to run ductwork.. But even so, the manufacturer dose not have to fill the entire cavity with insulation.

Basically in a nutshell, typical RVs will have about R3-4 in walls, and average of R4 in the roof even with "block insulation".

I have highly modified my TT when I gutted it, removed the fiberglass batting and used Polyisocyanurate foam board exclusively through out the rebuild. PolyIso has the highest R value per inch that you can get at R7 per inch but it is many times more expensive than your typical coffee cup insulation.

While my modification did help somewhat, it still is basically a hot box on wheels when you combine 80F and up temps plus high relative humidity. Basically to make a great big difference I would have had to stud in the walls and double or triple the thickness.. Then replace the single pane windows with double panes..

I do overnight without power when traveling and I have run into situations that just opening the windows at night was on the border line of insanity and that was even after running my A/C for a half hr to cool things down a bit..