You guys ask questions about things that, left to my own devices, I would never ask. That is good.
"Ice Dam Prevention - Just Google 'Gutter Guard Ice Dam Problems' ...
This well illustrates that there is some relationship with ice dams and gutter guards.
...melting snow refreezing at the eaves. Without gutter guards, this snow melt would refreeze in the gutter. With out gutters, snow melt often refreezes at the eaves. With snow, heat from the sun, heat from the house, and temperature fluctuations above and below freezing, there are going to be ice dams. The trouble with some products is where the ice forms.
With reverse curve covers, the ice builds on top of the product and becomes visible more quickly. This is true of many gutter guards. The only way to effectively eliminate the problem is to use heat to keep the melted snow from refreezing until it reaches the ground..."
The above may contain some
[ame]http://www.google.com/search?client=safari&rls=en&q=%22logical+fallacies%22&ie=UTF-8&oe=UTF-8[/ame]
but it does cast reasonable doubt on gutter guards being blameless.
Looks like MI is on this
http://www.nrca.net/consumer/attic_ventilation/ice_dams.aspx
map.