STARTED WALL BUILDOUT. USED 1X3 FOR FRAME KREG SCREWED AND GORILLA GLUED. DID FRAMES . ATTACHED TOGETHER MADE ADJUSTMENTS. WHEN IT LOOKED GOOD. TOOK APART AND SKINNED WITH 1/4 LUAN PLY AND SANDWICHED WITH 3/4 RIDGID INSULATION WITH FOIL BACKING FOR BETTER R VALUE