There are two components to financing a house build in Whistler, #1 the cost of buying the vacant land or land with a tear-down house on it, and #2 determining the construction cost of the build.
In Canada the borrower does not receive a lump sum from the lender in advance of the construction. The borrower must inject all their funds into the project before the lender will release the borrowed funds. The lender controls the draws ensuring the build has enough money to complete at every draw. Based on the budget any overruns need to be covered by your own funds, as the loan cannot easily be increased mid-flow.