ICF home with Sprayfoam attic however not enough material was applied so huge Ice dams | Ask Mason Knowles - SPF Consultant | Spray Foam Technical Questions and Answers | SprayFoam Magazine Q&A Forums

Q&A Forums

ICF home with Sprayfoam attic however not enough material was applied so huge Ice dams Post New Topic | Post Reply

Author	Comments
jmbeam59 Posted: Jan 06, 2018 07:26 PM	ICF home with Sprayfoam attic however not enough material was applied so huge Ice dams I have a 2400 sqft ranch with a complicated roof truss system. The Foam contractor did not apply a consistent amount of material and in some areas barely applied any! This is a bad winter with record cold temps and has huge ice cycles all over the roof line. It's really crazy and now water is entering the walls of our basement ruining the pain and sheet rocks that were glued and screwed onto the icf basement foundation. How would be the best way to fix this? I have two 5 gallons containers of spray foam and was going to spray along the attic where the roof edge is to seal this area and then I was going to blow6-12" of glass fiberglass over the entire floor. This is supposed to be conditioned space but we do not use it for anything else besides storing a few items. There are three skylights in the ceiling. My attic is huge, it seems like this design had so much wasted space but from the outside, the home looks great because of the expansive roof, I need to cure this heat loss problem and just wanted to be sure its ok to seal the entire attic with the spray foam and then apply a blown fiberglass blanket on top of the floor. ONly worried about all the recess lighting I have with LED and CFL lights. I don't believe they get hot enough to worry about fires. If there was a way to add pics I would. Thanks again
jimcoler I have over 10 years of experience specifying and installing open and closed cell spray foam. I've sold my business but I'm still selling for the new owners and consulting on large and custom specific jobs. I've expanded my knowledge into t Posted: Jan 07, 2018 04:42 AM	If you sealed up your attic with spray foam, even a small amount, I think the only solution is to have more spray foam applied to the roof and increase the thickness and R-value. I wouldn’t recommend applying fiberglass or cellulite on the floor of the attic because that won’t solve the problem and it will just make it worse when it does leak meaning it will cause the water to spread more! The only other way I can see to insulate the attic floor is to cut ridge vents and soffit vents but I don’t expect you’ll be doing that in the winter??!! So, I see address bf additional spray foam open cell or closed cell as you’re only option at this point! I hope this helps! Jim
mason Posted: Jan 07, 2018 02:47 PM	Ice Dams are caused by warm air from the interior of the house escaping into the attic and melting the snow on the roof. The water freezers and backs up onto the roof, then melts again into the building. In order to stop the warm air from getting into the attic. you need to seal and insulated the roof deck from the warm air rising into the attic. Additional insulation to the underside of the roof will help (more foam), but also pay attention to the outside walls that lead to the attic It is important that the interior walls at your roof edges be insulated properly in order to stop warm air from rising into the attic space from the walls. email me at masonknowles@aol.com and I will send you an article i wrote recently on the subject along with design details that show what to do and what not to do. By the way, do not add insulation to the floor of the attic, it just makes the insulation on the underside of the roof deck less efficient. Mason
Mister Posted: Jan 18, 2018 03:01 AM	One of the difficult things to discuss, that is never mentioned when contractors and homeowners have a problem, is what was the criteria for selecting the design and applicator for the job. Too many times, price is the only criteria. And there was no design spec for the project. When a job isn't performing properly, it could very well be a poor application, but who was hired? What was the specification? What was that based on? Many times people just get a bad product because all they care about is being cheap. And then they wonder why it isn't working. That may not be the case here, but those criteria never seem to be in these discussions, it's always just, " I have a problem" A quality Un-vented attic design, material spec, and application should not have ice dam issues even in a hard winter in your climate zone, so something is wrong.

Author

Comments

jmbeam59

Posted: Jan 06, 2018 07:26 PM

ICF home with Sprayfoam attic however not enough material was applied so huge Ice dams

I have a 2400 sqft ranch with a complicated roof truss system. The Foam contractor did not apply a consistent amount of material and in some areas barely applied any! This is a bad winter with record cold temps and has huge ice cycles all over the roof line. It's really crazy and now water is entering the walls of our basement ruining the pain and sheet rocks that were glued and screwed onto the icf basement foundation.

How would be the best way to fix this? I have two 5 gallons containers of spray foam and was going to spray along the attic where the roof edge is to seal this area and then I was going to blow6-12" of glass fiberglass over the entire floor. This is supposed to be conditioned space but we do not use it for anything else besides storing a few items. There are three skylights in the ceiling. My attic is huge, it seems like this design had so much wasted space but from the outside, the home looks great because of the expansive roof,

I need to cure this heat loss problem and just wanted to be sure its ok to seal the entire attic with the spray foam and then apply a blown fiberglass blanket on top of the floor. ONly worried about all the recess lighting I have with LED and CFL lights. I don't believe they get hot enough to worry about fires.
If there was a way to add pics I would.
Thanks again

jimcoler

I have over 10 years of experience specifying and installing open and closed cell spray foam. I've sold my business but I'm still selling for the new owners and consulting on large and custom specific jobs.

I've expanded my knowledge into t

Posted: Jan 07, 2018 04:42 AM

If you sealed up your attic with spray foam, even a small amount, I think the only solution is to have more spray foam applied to the roof and increase the thickness and R-value.

I wouldn’t recommend applying fiberglass or cellulite on the floor of the attic because that won’t solve the problem and it will just make it worse when it does leak meaning it will cause the water to spread more!

The only other way I can see to insulate the attic floor is to cut ridge vents and soffit vents but I don’t expect you’ll be doing that in the winter??!! So, I see address bf additional spray foam open cell or closed cell as you’re only option at this point!

I hope this helps!
Jim

mason

Posted: Jan 07, 2018 02:47 PM

Ice Dams are caused by warm air from the interior of the house escaping into the attic and melting the snow on the roof. The water freezers and backs up onto the roof, then melts again into the building. In order to stop the warm air from getting into the attic. you need to seal and insulated the roof deck from the warm air rising into the attic. Additional insulation to the underside of the roof will help (more foam), but also pay attention to the outside walls that lead to the attic It is important that the interior walls at your roof edges be insulated properly in order to stop warm air from rising into the attic space from the walls. email me at masonknowles@aol.com and I will send you an article i wrote recently on the subject along with design details that show what to do and what not to do.

By the way, do not add insulation to the floor of the attic, it just makes the insulation on the underside of the roof deck less efficient.

Mason

Mister

Posted: Jan 18, 2018 03:01 AM

One of the difficult things to discuss, that is never mentioned when contractors and homeowners have a problem, is what was the criteria for selecting the design and applicator for the job.

Too many times, price is the only criteria. And there was no design spec for the project. When a job isn't performing properly, it could very well be a poor application, but who was hired? What was the specification? What was that based on?

Many times people just get a bad product because all they care about is being cheap. And then they wonder why it isn't working. That may not be the case here, but those criteria never seem to be in these discussions, it's always just, " I have a problem"

A quality Un-vented attic design, material spec, and application should not have ice dam issues even in a hard winter in your climate zone, so something is wrong.

You need to login to reply to this topic. Please click here to login.