My daughters room is hot in the summer and cold in the winter. Tonight I decided to go in the attic and measure how deep the blow in insulation is. And it was 8'' at the highest spot but mostly about 6.5'' everywhere else, including my daughters room. How deep should it be? By the way if it matters my house was built in 2007, and it is a two story.
It depends. What zone are you in? Therefor, what does your code call for? Codes are minimums, btw. What will be holding the insulation up? Sheetrock thickness and joist spacing is....??? If the structure is there to support it, and you are in a cold place, pretty much "as much as you can afford now, and put the rest in later" is my answer. If I recall correctly, blown in cellulose (not sure what you have) is about R3.5/inch. R35-60 is pretty typical in lids.