There are three gutters in my yard now- that were recently on my house. After having a standing seam metal roof without snow guards for years, it took the Feb 2010 snow-zilla storm to make me change my ideas about these simple inexpensive devices.
We had a ridiculous amount of snow, all in one very cold 12 hour period starting at dark. The snow stacked up high on my cold metal roof- and then stayed for days. The peak would have a little sun, a lot of wind- and blow off and melt, running down into and under the snow blanket- turning to ice.
The ice overwhelmed the gutters- and then started making monster icicles. We’re talking 18 feet long (and I wish I’d taken better pictures). When the weather did break- so did some large chunks of the snow- straight down with a mighty crash. As each pan cleared- the gutters weakened- finally bringing them down too. Here is a good description of what happens- and what I should have done:
Unlike an asphalt or flat roof, the smooth surface of a sloped metal roof may create a dangerous risk to people and property, should a large ice flow break loose and slide off the building.
Snow guards for metal roofs
For this reason, snow guards were created.These ingenious little angle brackets act as “fingers” to keep ice and snow in place until it melts and disperses in a controlled way. Available in many styles, sizes and colors, snow guards blend in with any roof, and are hardly noticeable from the street. Many are high-strength, weather-resistant polycarbonate compounds that are bonded in place.
In more severe climates, snow bars or barricades are installed across the roof to safely retain larger flows. Metal snow guards are designed from aluminum, stainless steel or copper, and can be used on other roof surfaces, such as asphalt shingle or slate roofs.
via Snow Guards: Valuable Protection For Your Roof And Property.
Unfortunately, the gutter damage was more expensive than the snow guards would have been, but less than the deductible. Something to think about if you do have steep standing seam roofs with gutters.