That minimum is a floor, not a target. Putting down less than 20 percent means paying mortgage insurance premiums from CMHC, Sagen or Canada Guaranty, and Saskatchewan charges provincial sales tax on that premium at closing, so a slightly larger down payment can lower the ongoing cost of the loan.
The Home Buyers' Plan lets a first-time buyer withdraw up to $60,000 from an RRSP toward a down payment, and a First Home Savings Account adds room to save up to $8,000 a year toward $40,000 total, both without triggering immediate tax. Combining the two is common for a first-time buyer trying to clear the 20 percent line.
Where the down payment actually needs to land depends on what the specific house is worth, not a rule of thumb. Get your hand-reviewed valuation from Joel Dyck.