A tree limb comes down in a windstorm, or a section of shingles finally gives out in mid-January, and suddenly there’s an active leak with the forecast showing more snow. The instinct is to grab a tarp from the garage and get something over the hole before more water gets in. That instinct is right. The execution most homeowners picture, a tarp thrown over the spot and held down with a couple of bricks, is not.
A temporary roof repair done properly buys real time, weeks in some cases, until conditions allow a permanent fix. Done poorly, it fails within a day, sometimes taking a section of shingle or flashing with it when the wind finally rips it loose. The difference is mostly in a handful of details that aren’t obvious unless you’ve done this before.
When tarping actually helps, and when it makes things worse
Tarping is the right call when there’s an active or likely leak, damage is confined to a specific, identifiable area, and a permanent repair genuinely can’t happen right away because of weather, material availability, or scheduling. It’s the wrong call when the damage is spread across a large area, when the roof deck underneath is already compromised and can’t safely support someone walking on it to install the tarp, or when the situation calls for a full section replacement started immediately rather than a temporary cover.
A tarp is also the wrong tool when the problem isn’t a hole at all but a chronic ice dam backing water up under intact shingles. Covering the area with a tarp in that situation doesn’t address where the water is actually getting in, and it can trap additional snow and ice against the exact section that’s already struggling.
Why bricks and a loose edge fail within a day in Calgary wind
A tarp secured only by weight, bricks, cinder blocks, whatever’s on hand, relies on the wind never getting under an edge. On a prairie roof, that’s a bad bet. Once wind catches one corner, it works the whole sheet like a sail, and a loose tarp in a strong gust doesn’t just fail, it can rip nails or fasteners it was never properly attached to, opening up more of the roof than the original damage did.
Chinook winds specifically are the problem here, because they’re not a steady breeze, they’re a fast-moving pressure system that can produce sustained strong gusts with little warning. A tarp that survives a calm week can fail completely the first time a Chinook arrives, which is exactly the kind of weather event that also tends to be what caused the original damage in the first place.
Anchoring it properly means fasteners through the roof, planned deliberately
A tarp that’s going to survive real wind needs to be anchored into the roof structure itself, typically with furring strips, thin wood battens run along the tarp’s edges and screwed down through the tarp into the roof deck or framing underneath, spreading the load along a strip rather than concentrating it at a few brick-weighted points.
That means putting new fastener holes into a roof that’s already damaged, which is a deliberate tradeoff, not an oversight. Every one of those fasteners needs to be accounted for and properly sealed when the permanent repair happens, or they become their own small leak points later. This is one of the reasons a temporary repair benefits from being done by someone who’s going to be back for the permanent fix, and who knows exactly where every temporary fastener went.
Tarp material matters more in a Calgary winter than most people expect
Not every tarp sold at a hardware store is built for sustained cold. Cheaper polyethylene tarps get stiff and brittle at low temperatures, and a brittle tarp cracks and tears along fold lines and grommet holes exactly where it’s under the most stress from wind and the weight of new snow. A tarp that would last a full season in summer storage can fail in weeks once temperatures drop well below freezing.
Heavier-duty reinforced tarps, and proper installation that avoids sharp folds at stress points, make a real difference here. This is a case where the cheapest option at the hardware store is often a false economy, since a tarp that fails in a January windstorm means starting the whole emergency process over again, on a worse roof, in worse weather.
A tarp over snow and ice does not actually seal anything
Laying a tarp directly over existing snow and ice on a damaged section looks like coverage but isn’t a seal. Snow and ice underneath the tarp can still melt during a Chinook, and that meltwater has nowhere to go, since it’s now trapped between the tarp and whatever’s below it. Water finds the same path into the house it was already finding, just with an extra layer sitting on top doing very little.
A proper temporary repair clears loose snow and ice from the damaged area first, as much as conditions safely allow, before the tarp or membrane goes down. Skipping that step is one of the more common reasons a tarp job that looked fine from the ground turns out to have done almost nothing once someone finally gets up close to it.
Ice and water membrane as a better temporary patch than plastic alone
For smaller, well-defined areas, a self-adhering ice and water membrane, the same material used as underlayment on a permanent roof, can sometimes serve as a more durable temporary patch than a plain tarp, particularly once temperatures are cold enough that a tarp’s edges won’t seal well against the roof surface. It bonds more directly to the surface it’s applied to, provided that surface is clean and dry enough for it to adhere, which is its own challenge in freezing conditions.
This isn’t a universal substitute for tarping, since larger or irregular damaged areas still need a proper tarp system. For homes dealing with a recurring water intrusion problem beyond a single storm, a broader look at residential roof waterproofing service in Calgary covers the permanent membrane and flashing work a one-time patch was never meant to replace.
This is not a homeowner DIY job on an icy pitched roof
Every year, homeowners get hurt trying to tarp their own roof in winter conditions, and it’s not hard to see why. A pitched roof covered in snow or refrozen slush is one of the least stable surfaces a person can stand on, and the whole task usually happens under time pressure with an active leak already running.
- Climbing onto a snow or ice covered pitched roof without fall protection.
- Setting up a ladder on frozen or uneven ground without secure footing.
- Tarping alone in high wind, with no one aware you’re on the roof.
- Skipping snow and ice removal before placing the tarp or membrane.
None of these are risks worth taking to save a service call. Angel’s Roofing runs winter emergency calls with a full-time safety coordinator involved in how crews are equipped and dispatched, precisely because winter roof work carries fall risk that summer work doesn’t carry to the same degree.
How long a temporary repair should last, and the plan after it
A properly installed temporary repair, correct anchoring, appropriate material, snow and ice cleared before installation, should reasonably hold for weeks, long enough to get to a permanent fix once weather, material availability and scheduling line up. It’s not designed to be a season-long solution, and treating it as one risks the same failure modes a poorly done tarp job runs into immediately, just on a longer timeline.
The permanent repair plan should be discussed at the same time as the temporary one, not treated as a separate conversation for later. Knowing roughly when the permanent fix will happen, what it will involve, and what the temporary patch needs to survive until then keeps the whole process from turning into an open-ended wait with an unresolved hole in the roof.
A tarp is a bridge, not a fix
The goal of emergency tarping is simple: stop water from getting further into the house until a permanent repair can happen properly. Getting there takes more than a sheet of plastic and a few bricks. It takes anchoring, the right material, cleared snow underneath, and someone who can safely do the work on a winter roof.
If you’re facing an active leak this winter, get the temporary fix done right the first time rather than watching a rushed job fail in the next windstorm and starting over from a worse position than you began.
About the author: this article was contributed by Angel’s Roofing, a Calgary roofing contractor certified by GAF, IKO, Malarkey, Euroshield and VELUX, with a full-time safety coordinator overseeing winter emergency repair calls.
