Ice dams & roof leaks
Ice Dam & Roof Leak Damage
Water arriving at a ceiling in February. The roof is rarely the fault and the fix is rarely on the roof, which is why the same house does it every winter.
A brown ring appears on a bedroom ceiling in the second half of the winter, spreads over a few days, and then stops when it turns cold again. Almost everybody's first call is a roofer. Quite often the roof is fine.
What is actually happening above the ceiling
Environment Canada normals at the nearest reporting station put the Collingwood area near 278 cm of snow in an average year, which is a great deal more than most of southern Ontario and a consequence of sitting where lake-effect snow off Georgian Bay meets the escarpment. That snow sits on the roof. Heat escaping from the living space into the attic melts the underside of it, the meltwater runs down to the cold eave beyond the heated envelope, and it refreezes there. The ridge of ice that builds up holds the next lot of meltwater back, and water standing behind a dam gets under the shingles and into the assembly.
So the cause is heat loss and ventilation, not a defective roof — which is why replacing the shingles on a house that dams frequently produces a house that dams with newer shingles.
The part of this that is our work
What we deal with is the water that got in: a wet ceiling, saturated attic insulation above it, a wall cavity below the entry point, and whatever it landed on. Wet blown-in or batt insulation is the item most often missed, because it is out of sight, it holds a remarkable amount of water and it does not dry in place under a closed ceiling.
Why the stain reappears in a different place
Water entering a roof assembly does not fall straight down. It runs along the top of a ceiling on a vapour barrier or a joist until it finds a penetration — a light fitting, a bathroom fan, an attic hatch — and comes through there. The stain therefore marks the exit, not the entry, and they can be several metres apart. That is the single most common reason a repair aimed at the stain does not work.
Ceiling water damage and light fittings
A ceiling fitting that has taken water is an electrical hazard before it is a drying problem. Kill the circuit at the panel rather than at the switch, and leave it off. A recessed fitting in particular will hold water in the housing and give no sign of it from below.
Chalet rooflines on the escarpment
Complex rooflines with valleys, dormers and multiple levels — which describes most of what was built on and below the escarpment through The Blue Mountains and Craigleith — give meltwater more cold interior corners to stop in. Add a building that is empty midweek and unheated at the far end, and the first anybody knows about it is a ceiling that has been wet for eleven days.
FAQ
Ice dams & roof leaks — common questions
Should I get the ice off the roof?
Not with an axe, a hammer or a heat gun, and not from a ladder on ice. Damaging shingles in February converts a ventilation problem into a roof replacement, and falls from ladders in winter are the serious injury in this trade. Roof snow and ice removal is a legitimate service performed by people with the equipment for it; the permanent fix is air sealing and ventilation, done in a month when nobody is standing on ice.
The stain has stopped growing. Do I need anything done?
A stain that has stopped means water stopped arriving, not that the assembly is dry. Attic insulation above a stained ceiling frequently holds water for weeks under a closed ceiling, and that is exactly the condition mould needs. A reading from the attic side answers it in half an hour and is worth taking before you paint over anything.
Is an ice dam leak covered by insurance?
Water entering a building through the roof is treated differently by different wordings, and the distinction insurers draw is usually between a sudden entry and long-term seepage. That makes the date you noticed it and the date you reported it genuinely important. Photograph it, note the date, and report it before you start pulling anything apart.
Talk to a Collingwood water damage restoration company
Tell us where the water is, where you think it came from, and when you first saw it. Those three answers decide almost everything — whether this is an afternoon of drying or a scope with removal in it, whether it is likely to be an insurable event, and whether the honest advice is to stop reading and shut the water off first.