The customer called concerned about severe ice damming -- there was brown ice coming out of the vents at the eave soffitts. They wanted better insulation to solve the problem -- Sounds great!
We found so much humidity in his attic that the condensation would drip off the roof nails and soak into the plywood of the roof-decking. It turns out he's had to keep replacing his roof due to moldy rotted decking. Where does all that humidity come from? It's carried by the warm air that's escaping from the house below. How? Lots and lots of (hidden) holes in his ceiling! We found can lights that let the heat through, a chimney flue that was drawing the heat up into the attic, and an attic hatch in bad need of repair, just to name a few. Lastly, just as the customer suspected, there was not enough insulation. All this added up to ice damming. The heat they'd paid for was escaping up into the attic where it could melt the show on the roof. The melted snow would run down the roof to the gutter where it would re-freeze, creatinig a tall "dam" of ice that held liquid water against the shingles. This water found it's way into the attic where it soaked into dirty fiberglass, and then dripped out the vents, creating his brown icicles.