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Alfred
Icicles

I added about 10 inches of insulation to my attic (now have about 18 inches) and I still have a large amount if icicles on the edge of my roof. I don't think my attic is well ventilated. Could that be why I have so many icicles with all that insulation?

Fencepost
Re: Icicles

Attic ventilation serves two purposes: removal of humidity and equalization of temperature.

If you don't have adequate ventilation, your attic will be warmer than freezing and will cause melting of snow on the roof. When the meltwater reaches the overhanging eaves, it either refreezes causing an ice dam, or drips causing icicles. In order to prevent this, the attic must remain below freezing, or nearly so.

(Well, technically, it's the roof surface that must remain below freezing. The attic can be somewhat warmer. But if the attic is too warm, that will prevent the roof surface from maintaining a subfreezing temperature.)

Alfred
Re: Icicles

Thanks. Improved ventilation is what I will attack first in the Spring.

shu34an
Re: Icicles

An icicle is a spike of ice formed when water dripping or falling from an object freezes. Typically, icicles will form when ice or snow is melted by either sunlight or some other heat source (such as heat leaking from the interior of a heated building), and the resulting melted water runs off ...

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