Wall Insulation - What R-Value Should I Install?

Do you have video of diy next to plumbing pipes and electic wires thanks

I live in Minnesota you need R35 or you'd die in winter

This must be a different measurement between Australia and the United States. Your R-2.7 is R-13 in the U.S. That's not enough wall insulation for summertime heat. Closed-cell foam insulation will double the R-value, air seal the building, and waterproof at the same time. Now your problem is heat transfer through the studs. Add one-inch Celotex insulation on the inside before the 5/8" gypsum board. That will give you a decent wall. East and west walls get considerably more heat gain from morning and evening sunshine. There should be an additional heat barrier reflecting infrared on these walls.

Good question, Outback Australia during the 6 hotter than hell summer months, how about R7.0 ceiling and walls.