Friday, February 11, 2011

Photos of an Ice Dam

Dan from Massachusetts sent me a
couple of photos of ice dams.

Looking at the first photo very carefully,
I notice that there are 3 ice dams. The
first two ice dams are obvious as they
appear as two quite distinct ridges.
The third ice dam is not as obvious as
it is buried in the snow line:



Here's another photo of the same house.
To see the above photo and the below
photo in a higher resolution, click on
the photo. Clicking on each photo lets
you see the three ice dams quite clearly.


In the above photo, you can see
3 ice dams crawling across the
roof of the house. Again, the
ice dam that is highest up is
not as obvious as it is buried
in the leading edge of the
snow that remains.

I wrote to the man who sent me
the above 2 photos asking his
permission to publish these photos
on this blog. Here are his
comments in regards to publishing
the above photos:


Maybe it will stimulate further
discussion. I was really surprised
when the second (and third) dams
appeared - and it seemed like maybe
then it wasn't so good to clear unless
a) you have great insulation, or b) you
clear much higher so there's not much
snow above. We have had temps below
freezing several days with only a bit
of melting on this west exposure.

His experience parallels my experience
precisely. I've also had ice dam ridges
appear on the roof after clearing the
snow at two different levels. In my case,
clearing the snow twice produced 2 different
ice dams.

In my case, I used calcium chloride to
get the water flowing straight down the
roof. Calcium chloride is a type of salt
that effectively melts snow and ice up
to 25 degrees below zero Fahrenheit. I
threw it on my roof much the same way you
might throw rock salt.

All of this has become unnecessary for us
after my first cousin re-insulated our
attic. We do not have ice dams to any
significant degree any longer.

In life, it seems, there is the temporary
fix and there is the permanent solution.
More insulation is the solution that will
probably outlive me.

Ed Abbott

1 comment:

  1. Whoa! That's a thick pile of snow you got there. I used to experience ice dam ridges on my roof, but recently, a friend of mine suggested that I get better roof insulation so that ice dams won't form after clearing them, and it worked! I guess our old roof insulation before wasn't up to severe winters.

    Max Boughner

    ReplyDelete