Here we go , I have decided to remove all the cabinets and install a 2nd layer of insulation on the floor, walls & ceiling. The first is just not working to my satisfaction because the metal ribs under the plywood transfer to much heat or cold. IMHO the foam inside the walls is not worth bubkus !
With the old insulation I was picking up approx 10 deg over the exterior temperature. With this new lawyer I'm hopeful that I will be able to pick up 25-30 deg. My design goal is to be able to camp out in 25 deg F and be able to maintain 50 deg F inside without any additional heating other then ambient heat from my body, tv, fridge & inverter.
Currently also the 5,000 Btu ac is barely keeping up with the cooling load in full sun at 95 deg exterior temp, this upgrade should also have the same effect as upgrading to 8,000 Btu estimated, but for the exact same power of 500 watts.
In the next few days I will test the insulation and will see how it goes, I still have a small section of about 20-30 sq ft to install, hopefully tomorrow.
The foam board is from Dow Corning and has a R4 value for 3/4" thickness.
Cost is around $15 per 4 x 8' sheet.
Worst case I will have to install another layer -
but I may wait to do that in my next trailer.
Here is the wide open corner post with a hugh air gap
I installed a 2 x 3" and will install the foam around it,
Just a few more small strips to go