Insulation for 1.75" gap.

[qwerty11]

Have a 1.75" gap in my walls that will need to be insulated. Trying to decide how I should go about doing it. Its going to cost a good amount of $$$ to layer foam board insulation in a camper this size (7x10, 7'tall).

[Dale M.]

How about rolls of insulation materials they use to wrap air ducts with.... Its thinner than regular wall insulation....

Dale

[grant whipp]

I'd sandwich 1" and 3/4" Tyvek-backed foam-board from Home Depot or Lowe's ... actually, pretty cheap (I use the stuff for packaging up the windows I sell!).

Good Luck, and as always ...

CHEERS!

[Bogo]

I'd use 3/4" + 1", or 1/2" + 3/4" + 1/2" foil faced foam board. Place a reflective layer to the inside, and another to the outside. That way you get a bit of radiant heat reflection for both heat trying to escape, and heat trying to get in.