More pics of my neighbor's roof

[Moe]

Without an actual inspection, one can only go by the pictures you posted of just one side of the roof.

Initial observations are: Two power vents located on other areas of the structure, which don't come on during winter. I see no other forms of hip/ridge ventilation, and no other pod type vents. The bathroom soil stacks are noted, but no vents for exhaust fans in area (In my area, codes prohibit routing fans directly to attic area, and to soffit areas.)

Just some thoughts. Since it's a cathedral ceiling, the insulation is packed in cavity, keeping very well insulated, allowing the frost to remain on roof in this area, vs more heat loss in other areas.

It looks wet when no other areas are, probably because it is. It could be improper installation of insulation (no baffles) and/or lack of proper deck venting, and/or lack of proper routing of bathroom venting to the exterior.

Also noted is what appears to be buckling of shingles (curls) in this area, indicating lack of proper ventilation.

[Tony Hwang]

Hi, How about go upto the roof and down in the attic and look? Is it such a chore?

[George E. Cawthon]

No. the black areas are just the shingles.

[George E. Cawthon]

Yes, that is what happens. I suggest you take a course in what happens to roofs by looking around at your neighborhood roofs after it snows and as the snow disappears and after frosty nights; note the aspect (direction of the roof slope). You might want to note whether there is or is not frost or condensed water on the windshields of cars pointed north. Note that water can't pass through windshields, so whether is water or frost on the outside windshield surface has nothing to do with ventilation in the car.

[George E. Cawthon]

Because condensation can occur above the freezing point; look for dew on the grass every morning.

What you are seeing is a natural phenomenon that occurs when there is nothing wrong with a roof. I assume you are real, but you sound like a troll. Next you will think something is wrong if snow melts off the roof on the south side but stays on the north side.

[lp13-30]

We had a moderate frost here this morning and I looked at a lot of roofs on the way to work. Nearly every one had a frost pattern similar to the pictures. There may well be problems with the neighbor's roof, but the frost neither proves nor disproves anything. The roof-- and the house itself-- don't look that old, so my guess is that this is much ado about nothing. Larry