adding R-13 insulation on top of inswool

[ThermoJax]

I have alot of owens corning r-13 (the pink stuff) on top of the recommended amount of inswool blanket. But Pizzabob has some over the top calculations that seem to indicate that there can be too much insulation. On the other hand, I have seen time and time again here that you cannot have too much insulation. Now, maybe his calcs served to make him feel better about not insulating more, but hard to think that he could be wrong. I can still remove mine if need be. I can stand on a ladder and reach over the wall, as I haven't closed up the very top. Interestingly enough, the pink stuff does seem to "fill" with heat. I am hoping that after it fills with heat, that it then rejects it. Perhaps this filling with heat is what pizzabob speaks about. A usage of heat, rather like mass. A real low mass version of a alan scott bread oven.

[C5dad]

There is a point diminishing returns when it comes to insulation. In the chemical industry on piping, there is what is called the point of detriment when too much actually creates a greater heat flux, thus energy balance.

For what it is worth, do what you want as in reality, the heat balance is not as strict in the residential setting as it is in the industrial setting.

CW

[david s]

In my experience the fiberglass insulation tended to compress easily, making it difficult to work over, although if you are doing an enclosure rather than an igloo that would not be a problem.