Brevoort Park is a mature, established central neighbourhood, so new construction there is almost always an infill build on a single existing lot rather than a builder's subdivision, which is a separate point from the energy source question but shapes how that infill gets approved.
A builder still needs a City of Saskatoon building permit and enrolment in the Saskatchewan New Home Warranty Program regardless of whether the home uses gas heating, electric heating, or both, and a Saskatchewan lawyer closing the purchase, typically $800 to $1,500 in legal fees, confirms that enrolment before possession either way.
Confirm the specific mechanical systems in a builder's contract rather than assuming a rule that does not apply here. Get your hand-reviewed valuation from Joel Dyck.