# Insulating under HVAC trunk



## Windows on Wash (Aug 30, 2011)

No.

Seal all the seam and connection in the ductwork. Seal the boots to the ceiling.

What are you adding 2x10's for?

Blow the insulation right over the top of the ductwork and move it into the insulation layer.


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## Gary in WA (Mar 11, 2009)

I agree. Is that a skylight chase 1/2 insulated? Or just the gable-end? Add foam board or housewrap after the wall cavity insulation to prevent major degrading by wind-washing there. 

Gary


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## Rewound98 (Nov 16, 2011)

Thanks.

I'm adding the 2x10s so that I have catwalks to get to things if I need to in the future.

That's one of the catwalks in the picture that I've already built.

There used to be floorboards on top of the joists but I've removed them.

We don't need the attic space for storage and I'm not sure it is rated for the weight.

That's a gable-end in the picture. The part with the falling down insulation is conditioned space. If I'd panned to the right just a bit more you would have seen the section I've already enclosed with XPS. =)


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## Rewound98 (Nov 16, 2011)

BTW, I found this as a great reference that talks about the pros and cons of both approaches:

http://www.etccreations.com/hvac/atticducts

I'll be burying the ducts in the insulation for my solution.


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