Snow covered roof equals warmer house?

My biggest issue right now is ice dams. The roof is all slopes that dont connect except for at the garage which is a traditional shape. The main roof sections have no ventig whatsoever, and i am pretty sure insulation is minuscule and air leaks abound. Think for starters i am going to be cutting some soffit vents and installing some kind of vent up high at the peaks come spring. Maybe even install a tin roof which wont solve the venting issue but will help snow slide off dramatically easier

RickBlaine said:

A lady once broke up with me because we were driving by a Frank Loyd Wright house and I just could not keep my big mouth shut.

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That's a funny story. I have a friend who studied architecture and was a giant FLW fan, so I know the mindset.

FLW was your typical impractical architect, an "artiste." I have little patience with them. If the building doesn't work, it doesn't work. You wanna do art in 3 dimensions, do sculpture, I say.

Say, I wonder what maintenance problems those massive... er... buildings of Frank Gehry's have?

TheRambler said:

My biggest issue right now is ice dams. The roof is all slopes that dont connect except for at the garage which is a traditional shape. The main roof sections have no ventig whatsoever, and i am pretty sure insulation is minuscule and air leaks abound. Think for starters i am going to be cutting some soffit vents and installing some kind of vent up high at the peaks come spring. Maybe even install a tin roof which wont solve the venting issue but will help snow slide off dramatically easier

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I hugely endorse metal roofs. They cost some $$, but you don't have to redo them every 15 or 20 years, they're permanent. They reflect sunlight, so they're cooler in summertime. The make the snow slide off. Yay!

Hey hey, I've got a flat roof on half my house and love it, although I do have gutters. The central room has a 17' cathedral ceiling and having a flat roof on both sides makes it so easy to install a chimney on the central peak.
The trick for flat roofs is to make sure that you have enough supports at the design stage that snow load is not an issue. It also is mandatory to ensure that there is a modest slope that water runs off. Rubber membranes are awesome.

If you have a properly ventilated roof, then whether or not you have a foot of snow on top will have no effect on insulation.
What are y'all living in, an igloo?

I have 6 feet of snow around my cape style house (1800sqft) and its been -5 degrees the past 7 nights and I only been burning once a day in my wood boiler (15 pcs) and keeping up fine. Last year we have no snow and same temps and I had a much harder time keeping up (2 burns a day, 20-25 pieces). Let it snow!

Roof snow helps (though only a 1 foot up there b/c its metal), but the six foot of snow gives a real good wind break.

RickBlaine said:

....Why do you think all those farmers in Florida spray water all over their orange tree fruit if there will be more than 24 hours of temps in the teens? Because ice stays at 32 degrees and insulates what is inside- keeping it from getting colder.

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Well, not exactly. They use water misting in Florida because first the liquid water provides some heat to the fruit when first applied, providing 1 BTU/lb for each degree as it cools to 32 F, offset by the cooling effect of evaporation. Then, as it freezes, it gives up the heat of fusion (143 BTU/lb). As long as there is some liquid water in thermal equilibrium with the ice, the temperature will stay at 32 F. But once all the water has frozen, the temperature of the ice can fall toward air temperature. Snow is just ice crystals, with no liquid water on them (until melting begins). Snow will cool down to well below 32 F, according to the air temperature. But as with all insulating layers, a temperature profile will become established. The temperature of the snow exposed to the outside air will be fairly close to air temperature, gradually warming with depth toward the temperature of whatever is beneath the snow layer. Even if an attic floor or cathedral ceiling is very well insulated for moderate snow depth, a really high depth of light fluffy snow can add so much insulation that the temperature of the roof surface can be above freezing and result in melting of the snow (with ice dam or icicle formation at the eves). This is more likely to happen with a cathedral ceiling than with a properly vented attic space above an insulated attic floor.

Yes snow is a great insulator, i found this out by accident the other day. All weather reports were saying it was -2 out, my wifes car said -2 before pulling into the garage, for the life of me i couldn't figure out why my wireless thermometer was saying 18.. Well, after shoveling the roof, the spot where the wireless thermometer was mounted (deck rail) was now buried under a foot of snow. The lowest i have seen it go is 17.. (it was -9 this morning)

Simonkenton said:

If you have a properly ventilated roof, then whether or not you have a foot of snow on top will have no effect on insulation.
What are y'all living in, an igloo?

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That's a good point, however i could see the snow acting well as insulation on flat roofs.

As mentioned . . . on most roofs . . . I would not see the snow as acting as an insulator since the temp in the attic should ideally be pretty darned close to the outside temp if there is adequate venting.

Incidentally . . . I love my metal roof . . . not sure why I didn't go this route a long time ago. On the flip side, my cats hate it when the snow built up finally lets go and comes off in giant, noisy sheets.