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tohquestion
ice dams and insulating attics
tohquestion

Happy new year! New year, new ice dam...

Here's the question--Due to poor construction and continued remodeling, the heat ducts for the upstairs registers go to and through the attic and then back to the upstairs. Despite extensive insulation, still too warm an attic. I'm thinking of building a sub room in the attic and insulating under the rafters and installing a heat guard as well. Any advice, or other things I need to think about?
Thanks in advance--
Scot

Re: ice dams and insulating attics

Did you insulate the attic space or the duct work?
Is the duct lined or wrapped?
are the duct joints sealed with mastic?

Take a walk along the duct work and see if you feel hot air leaking.You may bad take off joints where the room runs leave the main trunk..If you have flex duct it can be ripped or the joints are dove tailed into the main trunk and need to be sealed.

Next have a thermal scan of the home .You will find all the areas of heat loss if you have tried everything else.
Happy New Year

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Jack
Re: ice dams and insulating attics
Jack

Maintaining air flow on the underside of the roof is essential. If you have ridge vents you should install channels from the sofit to the ridge vent before insulating. If you don't have ridge vents don't insulate between the rafters.
Jack

tohquestion
Re: ice dams and insulating attics
tohquestion

Here's more complete information: Two attics join together. One is the old part of the house. It has one layer of rolled insulation, then the flexible insulated duct work, then another layer of rolled insulation crosswise of the first. The new attic has insulated flexible duct work with 18 inches of blown-in cellulose insulation. All heat and AC ducts are in the ceiling. This is a bad design, I know, part of the problem was that this system was in place when I started to remodel the house. Part of the problem was the HVAC installer came off the same system to add to the new second story. The third part of the problem is that I was new to home redmodeling and didn't know any better. Now that I'm older and wiser, my plan is: if I can't stop the heat from escaping into the attic then why not insulate the whole attic. First continue the channels that are already there from the soffit to the ridge vent, then insulate the rafter space ( underside of the roof). The only other thing would be to rip down the ceiling in the first floor and redo the duct work so that it's in the floor of second story. This would cause much grief and a lot more money.
Any other ideas or comments on this plan would be appreciated.

canuk
Re: ice dams and insulating attics
canuk
Quote:

First continue the channels that are already there from the soffit to the ridge vent, then insulate the rafter space ( underside of the roof).

This would have merit. Depending how deep the rafter cavity is you may be able to use fiber glass bats ( not my favorite) then cover the those with rigid foam insulation sheets attached to the underside of the rafters.

Quote:

The only other thing would be to rip down the ceiling in the first floor and redo the duct work so that it's in the floor of second story. This would cause much grief and a lot more money.

Depending how effective having the heat ducts in the ceiling are this might be the preferable route.

Just my 2 cents.:)

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