The arch building is a fixture of farmyards around Stettler, and it is the one structure where geometry decides everything. There are no studs, no joists, no cavities and no flat planes. The wall is the roof, the roof is the wall, and the corrugated steel rib runs continuously from the slab on one side over the top to the slab on the other. Every insulation method designed for a framed building is the wrong shape for it.
Nothing cut to size fits an arch
A batt is a rectangle. A rigid board is a rectangle. The inside of a quonset is a curve with a deep corrugation running across it, so anything flat touches the steel at the high points and leaves a void everywhere else. Those voids connect to one another, which means air circulates freely behind whatever was installed, carrying heat out and moisture in. Strapping and panelling the inside creates an even larger connected cavity, and it is usually the thing that makes a quonset worse rather than better.
Water runs downhill, and the floor is downhill
In a framed building condensation forms on a cold surface and drips straight down onto whatever is below. In an arch it forms on the curve and then runs along the steel, down the sides, and collects at the base of the wall where it meets the slab. That is where the stored material is, where the equipment tires sit, and where the base of the steel corrodes from the inside. Owners frequently read it as water coming in at the slab rather than water that formed overhead.
Sprayed foam is the only shape that matches
Closed-cell foam follows the corrugation and the curve exactly because it is applied as a liquid. It bonds to the steel so there is no cavity left behind it, carries across the ribs rather than resting on them, and at about two inches is a vapour barrier, which keeps interior moisture away from the cold steel entirely. At roughly R-6 to R-7 per inch it also gets a useful number out of a building with no depth to work in. On an arch this is not a preference between materials; it is the only assembly that fits.
The end walls are the weak point
The arch itself is simple. The end walls are framed, they carry the large doors, and they are usually the last thing anyone details. Gaps at the junction between the end wall framing and the curve of the arch run the full half-circle, and on open country with sustained wind that joint is being pressurised continuously. It has to be in the scope or the building stays draughty.
Decide what it is storing first
Grain, equipment, chemical, hay and a workshop are five different requirements. A quonset storing seed and equipment wants an even temperature and no condensing surface; one used as a shop wants a sealed shell so a heater can keep up. The answer changes the thickness and sometimes the extent of the work, so it is worth settling before anything is measured.
We take care of the work
We do Quonset spray foam insulation Stettler ourselves. We scope and quote it, we book it, and our own installers spray it -- one company, one point of contact.
Quonset Spray Foam Insulation Stettler: Common Questions
Why can batts not be used in a quonset? Because there is no cavity and no flat surface. A rectangular product on a corrugated curve leaves connected voids that let air circulate behind it.
There is water at the base of the walls. Is the building leaking? Often not. Condensation forms on the arch overhead and runs down the curve to the slab, which looks exactly like water coming in.
Should the end walls be done too? Yes. The joint between the framed end wall and the curve of the arch is a continuous gap, and on open prairie it is under constant wind pressure.
How much does Quonset spray foam insulation cost in Stettler? It is priced per board foot over the sprayed area, and an arch has more surface than its footprint suggests because the roof and walls are one continuous curve. What the building stores sets the thickness before the area sets the total.
How do I choose a Quonset spray foam contractor in Stettler? Ask how they will treat the junction between the arch and the end walls, and whether the foam follows the corrugation. If they describe furring and panelling the inside, keep asking.
Size the assembly with the R-value calculator, then get a free Stettler quote. More on Quonset Spray Foam Insulation Alberta province-wide.