All weather camper

The bottom of the camper where the tanks are, is actually open. No need to open anything up. If I know what material would be best to use for insulation, I could simply create a bottom to screw underneath and then fill up the opening with material.

The camper has no wood in it (all aluminum and composites) so to create the bottom, I'd preferable use a bottom of aluminum.

I'm planning to pop the bottom off mine here later this summer, and add 1/2" foam insulation with a pressure treated or marine grade glassed 3/4" plywood bottom, and install it with screws....instead of the stock staples. I could use the extra 1.5" of space between my bed and the camper, and I'm kind of tired of having to have my camper floor supported all the time when there is anything in the tanks.

Here's how you do it:

1. Open up the cavity where the tanks are and assess the situation.
2. Determine how much room there is for insulation and whether the insulation will impede the functionality or serviceability of the camper.
3. Decide which insulating material will work best in the application. Multiple materials, such as spray foam (Great Stuff), fiberglass, and foam board may be required.
4. Install the insulating material as determined by steps 1-3.

Be aware that insulation does not prevent freezing. It only slows the process. If you put a camper in 0 degree weather long enough with no heat input, the tanks will still freeze no matter how much insulation you add.

It is likely that there will not be enough room in the basement to add any appreciable amount of insulation, so any effort will be wasted time and money.

Stay where you're at. There's no place better than Texas in Winter especially where you're at or further South. Many snowbirds wind up in Texas to beat the cold temperatures, so why would you want to be in a cold climate in Winter if you don't have to. This way you don't have to worry about heating your tanks or insulation.

Head south, no need to heat your tanks, who likes to be cold? Not me

What type of cold are you looking at?

Without knowing this suggestions are pointless as the temperatures will determine if your camper can even be made usable.

What does the bottom of the camper look like, and are the tanks built in to a basement area of the camper?

On our previous Northstar camper, I purchased stick-on tank heaters.

Then I covered the entire bottom with a 4'x 8' sheet of pressure treated plywood screwed into the camper framing.

You should first add some Heating Pads....they are sold at RV supply houses....no one can really tell you how to add insulation without seeing your specific situation....Additionally getting a camper ready for winter camping is not only about Holding Tanks.....