Attic Insulation - Plastic beneath/above fiberglass?

[Paul]

My ceiling "layer", starting from the bottom;

- drywall (the ceiling you see from the bedrooms)

- plastic sheeting

- fiberglass insulation, a thick layer

I'm wondering - would it be helpful/desirable to have another layer of plastic on TOP of the fiberglass insulation? Or am I already good?

Not an insulation expert, and just want to make sure I would be benefiting my energy bill, and not creating a vapour/condensation issue.

[greg6755]

You're good.

And you really don't to create a double vapor barrier.

That's not good.

[Joseph Meehan]

No and you only want one and unless you are in the deep south or somewhere that is very warm, it is where it belongs now. You can add insulation above as you like, but it should not have a vapor barrier included or the barrier should be cut to allow moisture to pass.

[Paul]

Thank you

[Paul]

Thank you

[Just Joshin]

imho:

Plastic it to prevent the migration of moisture through the insulation. So a second layer would trap moisture inbetween the sheets. Mold, poor insulation, etc, bad idea.

Understood, niether am I, just passing on information shared with me, when I upgraded my attic insulation.

later,

tom @