It’s the middle of winter, it’s cold outside and you discover water dripping on your floor. Your roof is fairly new so how can water be getting in especially when it’s freezing outside?
A good indicator of what is causing it are icicles and large amounts of snow around the edges of your roof. Unfortunately, if heat is escaping into your attic it’s melting the snow on your roof and causing ice damming. The melted water runs down to the roof overhang, which is not warmed by the attic but rather, cooled by the outdoor air. If the air and the overhang are below freezing, the water freezes and forms an ice dam. This can cause water to form a small pool which can build up under the edges of the shingles and leak through the underside of the roof, into the attic and potentially the walls and ceilings.
The ice can cause damage to your roof flashing, fascia and soffits and may even shift vents stacks and cause gaps to allow water into your roof.
To solve the mystery, you’ll need to identify where warm air is leaking into the attic. It can come from leaks around light fixtures, the attic hatch, etc. The problem can usually be solved by fixing the leaks and if necessary adding insulation to your attic.
Don’t try and remove the ice from your roof – it’s dangerous to yourself and the roof.
Photos source: NRCan Keeping the heat in – page 66
Here’s a question from one of our readers about possible ice damming and how she solved the problem. Thanks Karen for letting us share your experience. Hopefully it will help others.
Could excess humidity cause what may appear as a roof leak?
I’ve had problems with water on the floor, near the baseboard, in one of the bedrooms in my house, every winter. I thought that it was an ice-damming problem, since it only happens in winter, and have been dealing with the roofing company but they aren’t much help.
It happened again this year, but there’s no ice or snow on the roof and the windows were wet also. The humidifier was set at 30%, so I turned the humidifier down to 20%
I need to ask you some more questions to see if we can figure this out. 1. How is your home heated? Natural gas furnace, boiler, etc? 2. Does the water show up in the same spots every year? 3. Does the water appear below windows only? 4. How much water is it – small puddles, large puddles? 5. Does the water show up only near outside walls? 6. How old is your home and do you know how well your attic is insulated? Did the roofers look in your attic? 7. Do your neighbours have snow on their roofs?
I’m not sure what the problem is yet but answers to these questions should help.
Since I posted this I had the roofer and an Insulation expert check out the problem and found out what caused water to puddle on the floor under the baseboard on an windowless outside wall in an upstairs bedroom.
First, it was determined that the attic and roof were fine. No water, no leaks, dry as a bone.
After inspecting the bedroom and the basement utility room below, turns out that the culprit was a) the house was too humid, and b) an exposed gas pipe in the basement utility room directly below the bedroom was allowing cold, moist air to travel up the wall and then condense upstairs, creating a puddle of water on the floor at the baseboard.
The humidity was set at 30%, but it was too high because the windows were wet and runny. I’ve since turned it down to 25% and the windows are fine and I’ve not seen the water since. The insulation company is coming in a few days to blow some insulation around the gas pipe and joist headers to make sure that the area is sealed up.
The other interesting thing about this situation was that it started after I upgraded the windows and doors in the house, as well as installing a new roof. The house was no longer as drafty, which created a condensation problem with that exposed pipe opening.
So it has a happy ending with a comparatively inexpensive fix–$400 bucks vs thousands to tear apart a roof or re-insulate an attic!