kok328

Do gutter guards promote ice damning?

What's the consensus?

nealtw

Ice dams are caused by heat leaking from the house over the outside wall melting the snow and re-freezing a little lower down the roof. As the snow melts, there is no place for water to go and it backs up into the shingles.

oldognewtrick

Gotta agree with Neal on this one. The bigger problem is heat loss through the roof, melting snow and causing problems. Gutter guards would not be a factor in ice daming because they would be the same temp as the air. But thats just my uneducated

Wuzzat?

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
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.

nealtw

Ok, let's say the cause dams at the gutter. On a 3/12 roof with an 18" overhang. You would need 4 1/2" of ice before the water would be over the exterior wall and over 9" to have go past the first layer of felt. I live in a warmer zone but that sounds like a alot of ice build up from heat from the sun while it is still cold enough to freeze. Just saying.