As homeowners weigh federal rebates of up to $10,000 for energy upgrades, a clash between DIY heat loss apps, professional heating engineers, and municipal grid warnings highlights a complex calculation over how much heat a property actually needs.
Cool Calc, Heatpunk, and the Rise of DIY Heat Loss Surveys
Getting this figure right is essential for sizing a heat pump precisely. An off calculation leaves property owners with an underpowered device that struggles to warm the building.
Beyond Cool Calc and AutoHVAC in the US, UK homeowners use web apps such as Heatpunk. Andy Rankin, founder and managing director of Midsummer Energy, notes that thousands of people use Heatpunk every month—mostly professional installers—to draw floor plans, input property data, and estimate performance.
Dwellow, a UK heat pump installation firm, recently launched its own heat loss estimator to streamline initial property checks. Ian Mclaren, Dwellow co-founder and director, suggests that self-surveys could reduce professional survey time down to a half-hour trip.
Oversized Systems Consume Excess Power
“The heat loss calculations often led to overestimating the design heat loads by a factor of two or more,” says Kevin Kircher at Purdue University, which results in oversized systems consuming excess power. Study participants reported charges exceeding $1,000—and in one case reaching $2,500—just for a single heat loss survey.
Dan Dempsey, a former senior engineering fellow for a major US heating and cooling provider who participated in the Purdue study, uses smart thermostat data in Indiana to monitor heating systems. Dempsey notes that oversized systems cycle rapidly on and off, creating discernible temperature swings and physical discomfort where rooms fluctuate away from target temperatures like 20C.
“I spent five years manually downloading everything, every week,” says Dan Dempsey, a former senior engineering fellow for a major US heating and cooling provider who participated in the Purdue study.
Industry Skeptics Question Homeowner Calculation Value
Industry experts offer contrasting perspectives on whether property owners should handle their own heating calculations. Maurizio Sibilla of the Centre for Advanced Built Environment Research at the University of West England, Bristol, argues that solutions stem from better installer practice and customer-facing evidence rather than expecting homeowners to do the engineering themselves.
Saskatoon Officials Warn of Costs
While homeowners explore heating estimates, municipal officials in Saskatoon raise distinct warnings regarding utility bills and emissions. A federal government recently announced a $2-billion investment supporting home energy upgrades across Canada, offering heat pump rebates up to $10,000 for eligible households below median income, and $2,000 for other homeowners.
Buildings currently account for roughly 61 per cent of Saskatoon’s greenhouse gas emissions. To address efficiency holistically, Saskatoon operates the Home Energy Loan Program, letting residents borrow for insulation, windows, heat pumps, and solar panels while repaying through property taxes, accompanied by a $1,000 assessment rebate.
