I have odd sized rafter, wall stud and floor joist bays and Larsen trusses to boot with no top plates. This poses a problem in calculating the quantity of cellulose I need to get the optimum R-value (assuming the best is 3.5 to 4.0 lbs/ft3) in my all season cottage.

Can anyone point me to a formula on-line that I can punch in my numbers and get the volume estimates for my different dimensions of cavities at different densities (R values)?

Are there recommended, reasonably priced, infrared cameras that I can use to check a contractors or my own work, as we go, when blowing into blind cavities, behind drywall, etc?