If I have a 5 1/2 in. square framing bay and the exact same 5 1/2 inch square batt, does it matter which way I install it?
RichG44
| Posted in Energy Efficiency and Durability on
Does fiberglass work directionally? Or does it matter?
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All I got for an answer from Owens Corning was it doesn't matter.
However, when you blow on the front or back side with an air hose, the air only penetrates so far while blowing on the side, it blows apart.
Same when I pour water; on the face, it very slowly gets on the floor. While when I pour it through the side, the water immediately hits the floor.
I am looking for some scientific proof, but cannot find any online.
If Owens Corning is willing to place that answer in writing, that's your answer.
Rich,
My guess is that it doesn't matter -- especially since such a small framing bay (5.5"x5.5"x5.5") makes up such a very small percentage of your wall area.
Remember, when blown-in fiberglass is installed, the fibers arrange themselves randomly.
Other factors -- for example, how well the insulation is inserted into the bay, and whether there are any voids or compression -- are likely to matter far more than a very small (theoretical) effect due to fiber orientation.
Rich, is this in fact a small part of a wall, or something else entirely that requires effective insulation? Because you can do better than fiberglass batts if performance is a priority. Fluffy batts are cheap and cover a large area efficiently but they're certainly not state of the art insulation.
I have been insulating for over 17 years. Have sprayed a lot of poly urethane foam.2.5 pound and even some half pound faom. I am working in a new area and apparently it is common practice to install natty sideways. In corners or in a wide bay to fill the remaining gap a 15 inch or 23 inch batt won't fit.. obviously there are far superior materials to use rather than fiberglass. It drives me nuts to see the sideways batt and see it as a lazy way to insulate.i am looking for thermal pictures of these Batts installed sideways , ( or not face out)