I have a stick built 24x24 garage. No coverings on the walls Just 2x4's
no celing.I want to insulate my first question is in what I have read here the rafter are insulated over putting in a celing and venting the roof. Why and what is the pros and cons of both.I need cheep and easy. Is drywall and blown in idea for the side walls.Or is the pole bar wrap cost afective and cheaper after the time factor.? Thanks for any and all help Ken.
Are you insulating for heating, cooling or both?
Your question(s) regarding "... the rafter are insulated over putting in a ceiling and venting the roof" is not clear to me. If your design has vaulted ceilings or you want to be able to actually use the attic space (2nd floor or storage), then I think you'd need to insulate the interior roof deck most likely with rigid foam board and the appropriate air gap or spray foam. Otherwise, just insulate above the ceiling using either batt or blown-in insulation.
If the interior walls and ceiling (sheetrock, osb, plywood, etc) are not installed yet, adding a vapor barrier first helps control moisture from saturating the insulation on the cool side of the barrier.
If your interior walls are not up yet, use batt insulation or spray foam before putting in the walls. I think it'd be easier then using blow in insulation which requires some retention barrier to contain the blow-in before the walls are attached. All three of those methods are WAY easier than blowing-in insulation after the interior walls are up which requires boring access holes in each and every stud bay for the blow-in applicator hose. (I am facing this dilemma since my interior sheetrock walls are already installed.)
Not an expert but I still hope this helps...
Paul
Paul