I just got finished with insulating my GN today! Mine is small. 3' short wall. I just did the ceiling and the floor since mine already had the sidewalls done by the factory when I purchased it. It took my dad and I two days to do it. I used 1" foam board with aluminum foil on both sides on the ceiling (Home Depot) Was $26 bucks a sheet (4x8) I used 2 sheets of that. We did not glue to the aluminum ceiling. Our cuts fit tight between the beams and I will tape it along the edges tomorrow. R-value is 9.5? I think or maybe that was the 2" thick ones we got for the floor. On the floor, which I did from underneath because I already have rug on the inside floor and plywood underneath that and I didn't want to have to rip out the rug and such. There is no aluminum flooring under the plywood so I added the 2" foam from underneath.( Will see how that holds up.) I used 2' foam board. Again... aluminum on both sides at $30 a sheet from Home Depot as well. (I bought two sheets 4x8) I think that was the one that had the 9.5 R value. I figured go with the best since this is probably my last trailer and I don't want to be cold anymore while camping! Anyways, we glued that to the bottom but again, our cuts fit really tight in-between the beams. We tapped the foam boards in using a piece of 2x4 wood and a rubber mallet all along the foam board until it fit tight and snug in-between the beams. My next step will be insulating the neck of the GN. Later, I will be installing a refer and a "cowboy shower" set-up. My trailer is a 2-horse slant all aluminum gooseneck. | 
LQ Insulation
