I recently bought a house in Kansas city that was built in 2002. It is of the cap cod style and is 1.5 stories. I spent some time investigation how the house was built and what insulation was used. The two bedrooms upstairs which have slopped ceilings and knee walls don't seem to be insulated correctly. The cathedral ceilings has 2x6 rafters with r30 insulation in them. There isn't any air space between the sheathing and the insulation. The insulation is faced toward the warm side but no extra vapor barrier was installed. I assume the entire roof is insulated this way. I don't notice any wrong and didn't see any mold/condensation issues on the sheathing but I don't think this is the correct way to insulate. Also the rafters are insulated behind the knee walls along with the knee wall itself. I though it was supposed to be one or the other. What problems are caused by having both insulated?