So what’s up with this? Picking my grandson up from school and ran across this house. And it was not the only one, there were several in the neighborhood like this. What’s your thoughts?
The roof matches the ground. What are you seeing?
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Maybe the first story foyer/porch roof?
Without inspecting the attic spaces there’s no way to tell if there is a lack of insulation, poor ventilation, an uninsulated whole house attic fan, etc..
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I have a friend who installs insulation. He will use melted snow on a roof as a reason to knock on the door.
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Well, it’s usually the opposite. The melted snow is where the rafter bays are. The snow that didn’t melt is where the rafters are. This suggests that the rafters are providing more insulation than the space between.
If you have frost or snow on the roof, that is a sign that the living space is properly insulated! In other words, the attic area is close to, if not the same as, outside temperature because the conditioned, heated air does not leak into the attic space.
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Black shingles. Solar radiation from the sun heating the roof. Rafters heating up slower than the shingles and sheathing because of rafter thermal mass and slower flow of conduction energy transfer.
You see the opposite on a cool morning at sunrise, but radiant energy moving the opposite way. The roof loses radiant energy to the night sky and forms frost on the shingles, even when the temperature is above freezing. The rafters have no frost, forming telltale frost free lines on the roof. Same applies to frost on your car windshield, even when above freezing at night.
First floor shed roof: Add the above to reflection of radiant energy because of the glass coating on the window. Heat loss from the home interior may be a factor, or not.
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The presence of snow or frost along the rafters but absent in the bays tells me there is a concern with the insulation where heat is escaping into the attic. But I’m asking because its been a very long time since I have lived where it snows, like 30 years.
And the spaces between the rafters or trusses that show an absence of snow, but the rafter lines have snow?
Not enough information in the OP’s post. An informed guess is just that, one that considers all the information. One item not even considered is what compass position that side of the roof faces. With that considered you would then look at the other roof faces. A WAG is just that - a Wild Ass Guess!
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The roof faces west. But this will not explain why there is snow on the rafters, but not in between. I failed to take photos of surrounding houses with the same directional facing that have snow across the full plane of the roof.
A rafter is a solid piece of wood touching the cold roof sheathing along its entire length. That makes it a very effective cold sink.
It continuously conducts cold downward from the roof surface.
The spaces between rafters are warmer slightly from attic air.
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your picture shows me that it is winter where you are….nothing more….
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Ground and roof have roughly the same amount. You’d need a larger accumulation to go the down the road you are going down…. especially, when you say there are other nearby houses that are the same.
I once saw a picture that I wish I had saved - one house in a new subdivision with a bare roof and all other others with several inches of snow. In that case the insulation likely got overlooked.
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Actually, what I think I said was there were other houses in the neighborhood with the same facing slope but snow covering the roof. Anyway, its a curiosity that will only show up occasionally, when the snow melt has been sufficient.
I am leaning towards the heat/cold sink effect as Marcel mentions. It’s honestly such a light covering of snow, I’m not sure I would try to draw too much conclusion just from looking at the one picture. Another possible scenario, warmer outdoor air, moving up the soffit venting towards the ridge, between the rafters.
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There is insufficient information without seeing the attic. What was previous and current temperatures? Did it just snow or has it been there a month?
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Exactly…
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First thoughts.
They’ve had a dusting of snow.
High entry so must be in a flood zone
Not a particularly attractive house
If that front fence is wood it will look like shit eventually
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