Steel buildings here have a different problem profile from the rest of Alberta, and it is worth being precise about, because it changes what you should be watching for.
Condensation here is seasonal, not constant
In a humid climate a steel building sweats more or less whenever it is heated. Medicine Hat's air is genuinely dry for most of the year, which means less airborne moisture available to condense.
That does not make the building immune. It makes the problem episodic - and episodic problems are the ones that get misdiagnosed.
The moisture usually comes from inside rather than from the weather: an unvented heater, vehicles bringing in snow, washing, or a process that puts water into the air. On the days those coincide with a cold deck, you get condensation. On other days you do not.
So the tell here is not a constant drip. It is damp that appears occasionally and cannot be tied to rain - which is exactly the pattern people chase as a roof leak for years. If your building is dry during a downpour and wet on a cold morning, the water is coming from inside.
The frame is still the weak point
Whatever the climate, steel conducts. In a metal building the structural members run continuously from the cold exterior to the warm interior, so every purlin and girt is a thermal bridge and a strip of interior surface markedly colder than the panel around it.
That is why the classic failure appears as stripes - lines of condensation, frost, rust or staining following the framing exactly. Those are simply the coldest interior surfaces, and moisture finds them first.
Blanket insulation compresses precisely where it crosses the steel, so it is thinnest exactly where the bridge is worst, and it does nothing about air movement. Closed-cell foam adhered to the underside is continuous over the purlins, leaves no gap for air to travel in, and at adequate depth keeps the dew point inside the foam rather than on the steel.
Add the summer case
In this much sun, an uninsulated steel deck is also a radiant heater for half the year. The same continuous layer that solves the condensation problem cuts the afternoon heat load. Worth counting when you weigh the cost.
Fasteners and long-term corrosion
Repeated wet-dry cycling on unprotected steel and fasteners is what drives corrosion over time - and episodic condensation still cycles, it just does so less often. See preventing rust in a steel building.
Before the quote
Settle what the building is used for, whether anything inside adds moisture to the air, whether heating is continuous or intermittent, and what has to cover the foam. See thermal barrier vs ignition barrier.
What we do
We are a referral service. We do not install. We connect you with vetted installers - certification, insurance and WCB standing checked.
No price without a site visit. Get a quote, and say whether the damp is constant or occasional.
See also metal buildings province-wide.