A quonset around Edmonton spends more consecutive months below freezing than one in the south, and that changes which failure you get. Southern arch buildings mostly fail on cycling. Here the shell simply stays cold for a long stretch, and the problem becomes what happens every time you heat the inside of it. Quonset spray foam insulation in Edmonton has to hold through that unbroken stretch below freezing.
Heating a bare arch is what starts the trouble
Most of these buildings were put up unheated, to keep snow and weather off equipment. Then a heater goes in so someone can work through winter. That single change turns a cold, dry shed into a warm, humid space wrapped in cold steel, and every square foot of that steel is now a condensing surface. The water that appears is not coming through the roof; it is coming out of the air inside the building.
Snow load and meltwater are their own detail
An arch sheds snow well until the building underneath is warm. A heated, uninsulated quonset melts the layer touching the steel, which refreezes at the cold eave line. Insulating the inside face keeps the shell cold on the outside, which is what you actually want - the roof behaves like an unheated roof again and the melt-refreeze cycle at the edges stops.
Why the arch has to be foam
The curve gives batt nothing to sit in and board nothing to sit against, so any other product leaves an air gap between the insulation and the coldest surface in the building. That gap is where moist air ends up. Closed-cell foam bonds to the steel with no cavity behind it, which removes the condensing surface rather than hiding it.
Practical notes
- Insulate before, not after, the building is put into heated service, if there is any choice about the order.
- Existing rust gets addressed first; foam should not be sprayed over active corrosion.
- Frost depth and a long closed-up season make sealed water lines and pump enclosures worth doing at the same time.
- A code-compliant thermal barrier is still required over the foam for the building's occupancy.
What an Edmonton yard usually wants done first
Where a property has more than one arch, the one to start with is rarely the biggest. It is the one holding whatever the damp actually harms, because that is where the condensation is already costing something rather than merely being a nuisance. On an Edmonton yard that is usually the building with equipment or feed in it rather than the one used for cold storage of steel and pipe, and treating it first buys the most for the least.
Quonset Spray Foam Insulation Edmonton: Common Questions
Why is a quonset so hard to insulate? The curve. There is no cavity and no flat plane to fasten to, so foam is one of the few materials that follows the arch continuously.
Does it get cold enough here to matter? A quonset around Edmonton spends more consecutive months below freezing than most of the province, so an unheated one is condensing for a long stretch.
Will it stop the dripping? It removes the cold surface the moisture forms on, which is the actual cause rather than a symptom.
Work out the thickness with the R-value calculator, then get a free Edmonton quote. See quonset insulation province-wide or agricultural spray foam in Edmonton.