Ice creep on low slope roof

Roofing/Construction Questions
#1

Hi guys,

I have a Cape with a full shed dormer. The dormer roof is rubber or some other membrane, South facing, and roughly 14x30. The slope is 2 or maybe a little less. In winter ice builds up at the eaves creating huge cornices and icicles and eventually it slides off in deadly chunks, sometimes as big as a 30 gallon drum. The gutter below has been destroyed.

A few years ago we installed a ridge vent and soffit vents across the front of the house to alleviate ice dams, but didn’t install soffit vents on the dormer eave… would that help?

A G.C. recommended that I install an array of snow guards. But as he is just a G.C. and had never done that before, I thought I’d ask the pros… does this sound like a good application for snow guards?

Any other suggestions?

Question 2 - The house has gable vents and I’m getting the impression that the closing them off might help the ridge/soffit arrangement to work more effectively. Is that correct?

Thanks so much!
Robert
Stow, MA

#2

It could work. Just a different method of installation. But you can’t just install them along the eave. You have to employ a system that will hold the ice in one place, not just catch it as it slides intot he guards.

Snow Guard Installations

#3

Soffit vents on the dormer will help IF the under-deck space breathes with the rest of the attic. If not then 3 or 4 inches of foam under the low slope will slow down the heat transfer.
good luck