Lees Summit Roofing Contractor: Ice Dams Impact – Part Two

In an earlier blog, I explained what an ice dam, how it forms, and trouble it leads to.  If you see evidence of an ice dam forming, you need to address this immediately.  And this isn’t the time to install a new roof, although when you need a new roof you have additional opportunities to address ice dams.

 Ice Dams are caused by warm air in the attic melting the exterior snow, and solving this problem is the first step in getting rid of ice dam problems.  You need better attic insulation to prevent that heat from your comfy, warm house from getting into the attic space to start with.  And this has the added benefit of saving you money on utility bills and making your furnace or heat pump run more efficiently (you are paying for all the heat that escapes).  I recommend a minimum of R-50 insulation over your ceiling joists, and this corresponds to at least 14” of blown in, dense-packed cellulose.  This isn’t 14” installed height (it is light and airy when blown in), but 14” after settling.  This probably corresponds to 18” of installed height.  Code minimum in Lees Summit is R-30 for ceilings, and this is insufficient to prevent ice dams from forming.  Minimize the warm air escaping to the attic and minimize that snow from melting in the first place.

 Ice dams are caused when snowmelt from your roof hits the cold area at the eaves of your roof.  This cold area refreezes the water before it can drain off the roof.  This is a second opportunity in preventing ice dams (some would consider this the first, but insulation can be done from the warm confines of your home and not outside).  You want a long-handled snow rake, available at many home improvement stores or through the Internet.  Every time it snows, you need to get outside and get the snow off your roof.  I wouldn’t worry about all of the snow; I would worry about the snow over the eaves where the ice dam forms.  This way, any snow melt that forms over the heated area of your house (although minimized through additional insulation) has a straight (and fast) shot into your gutters, and once it is in your gutters it is off the roof and not causing or perpetuating an ice dam.

 Lack of insulation isn’t the only common heat source from your living area into the attic space.  Do you have recessed lighting (can lights)?  People love them; they look fantastic.  Builders love them because they are cheap and people love the elegant look.  Builder’s grade can lights have a unique feature in that they build-up heat and have to have a way to shed that heat.  In doing so, you have to keep insulation at least 3-4” away from the housings, otherwise they overheat.  And they also have vented housings.  Do you use a chimney starter for your charcoal grill?  Once that fire gets started, it creates a chimney effect as heat rises, and fresh combustion air is drawn in through vents in the bottom of the starter.  Well, that light bulb in a can light operates the same way; heat (from the light bulb) rises and vents, and makeup air comes from directly inside your house.  Every can light you have is approximately one square foot of uninsulated attic, and to make matters worse they also create a chimney effect pulling even more of your heat into the attic space.  And what does that heat do?  It melts snow, and that creates ice dams.  Can lights need to be properly sealed in the attic, and have sufficient insulation around them to prevent heat loss.

In Lees Summit, you can plan on using that roof rake several times per year.  These are items you can do to prevent ice dams without calling a roofing contractor.

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