Frost On Roof

Frost on roof it s that time of year when we occasionally have frost on our roof tops.

Frost on roof.

1 initially the air and the car are at temperature 37 f and the dew point is 35. Once in the attic it warms the air over the living space. An ice dam can damage both your roof and the inside of your home. Homes that let heat escape more rapidly than others will keep ice on the overhangs but not over the living area.

That heat then conducts up all the way to the shingles. And here s the clincher. An ice dam is a hump of ice that forms at the edge of a roof under certain wintertime conditions. When warm air from inside the house escapes traveling up through the bypasses the moisture condenses on the roof boards and rafters where the frost can form.

These dams can tear apart your home so limit them by keeping your roof clear of snow. 2 the car roof cools radiatively. However if nothing is different about your home compared to your neighbors you may have a problem. If dams are a serious threat to your roof the problem is usually due to poor ventilation.

If you see icicles hanging from your roof you most likely have an ice dam. Is the absence of frost an indication of heat loss thru the roof via poor insulation. When the outside temperature rises again the frost thaws water collects and can leak into your house. Ice and water protector sometimes also referred to as ice and water shield is a waterproof roof underlayment membrane developed to protect vulnerable areas on a roof from ice and water damage.

A lack of frost can indicate that heat is leaking out through your attic space onto the roof and melting the frost. During winter conditions attic frost is a problem associated with attic bypasses. Ice dams happen when ice melts trickles down the roof then freezes again. If the morning sun directly hits your home and not your neighbors lack of frost may just be attributed to the sun s heat.

Now comes the ice or snow torrent and you are under insulated. Ice and water protectors sometimes called ice and snow shields in cold climates are made with polymer modified bitumen. The overhang porch and garage keep ice on them longer. This leaves a border of frost on the outside edges of the living area.

Something i implied above but didn t say explicitly is that when frost forms on the roof the roof is below freezing. In other words the sequence might be as follows. That warm air makes contact with the roof deck and warms it up. Ice dams are a common sight in northern new england winters and home partners has dealt with quite a few.

Warm shingles don t allow frost to form as readily as cold shingles.