Putting insolation around the steps is easy just take the step plate out and glue and tape the material to the back. as for adding under the carpet I don't think you can, one reason that it is glued to the dog house and there is some padding under the carpet
We insulated the cabinets in our 378 to reduce the heat here in Florida. Used foil insulation board and secured it with the aluminum tape. Reduce the temps significantly.
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2014 Georgetown 378 XL
Toyota Prius on dolly.
Full time since 2014