On a frigid, 40-below night in February or a broiling, 30-above day in July, would you feel comfortable having a long nap inside an under-insulated shed? Potatoes don’t either. The good news is that virtually everyone is pushing for more insulation R value today.
Spray foam insulation now offers better fire retardant and more food grades than earlier generations of foam. The main change, however, comes in depth. Virtually across all potato growing regions in Canada, producers have been opting to increase spray foam application by a full inch or more over the past few years.
Prairie farmers used to average about five inches of insulation while Maritime growers pushed it to about six. Today, growers across the country are opting for between six and seven inches of insulation.
While adding more insulation can feel like a hefty upfront cost, it pays off for growers who can store better quality potatoes longer. Return on investment isn’t just in the form of quality: some growers tell me they might be able to get better contracts from processors simply because the processor knows they have a better building.
Growers considering a new build should commit upfront to investing in insulation rather than planning to retrofit later, as insulation won’t adhere as well to dirty walls. No matter whether spraying a new building or an existing one, it’s always better to spray less rather than more in a single pass. Though some companies advertise that their foam can be sprayed to a depth of 4.5 to five inches in a single pass, you only need to see a pile go soft because of uneven insulation once to understand the benefits of controlled and precise spray foam application.
Growers willing to invest more in insulation have a couple of options. Traditional insulated panels offer enhanced cleanliness at a substantial price: plan to add about 15 per cent to your building cost. Some companies offer a double-wall design with an internal air envelope. However, because other arch-style buildings can’t handle the weight of an additional wall, the internal wall has to stand alone. Typically, this forces the building envelope to be much wider than otherwise necessary: usually six to seven extra feet on each side.
We are the first company to offer internal steel sheeting over a slim air void. Meridian’s design is a steel sheeting wrapped over the chosen amount of foam and desired air void space (typically just a couple inches). While seam-system buildings can’t carry the load, our archwall’s bolted structure allows the new bolt-in system.
This design offers the benefits of exposed foam protection, which protects the foam and is better for food safety, at a reasonable price (expect about two to three per cent of the building cost), without the cost of valuable storage space being used up by the air envelope. Ultimately, that means more insulated value with less future maintenance.