Rental Cash Damming Calculator

See how redirecting rental income to prepay your mortgage — funded by a tax-deductible HELOC — could change your payoff timeline.

① Rent comes in

Every dollar of rental income prepays your primary mortgage.

② HELOC pays the rental's bills

Rental expenses and the rental mortgage payment are paid from a HELOC.

③ Interest becomes deductible

HELOC funds were used to earn rental income, so its interest is tax-deductible → CRA refund.

④ Mortgage dies early, then attack the HELOC

Once the primary mortgage is gone (years early), the old payment + rent aggressively pays the HELOC.

Rental Properties

Rental Property 1

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Exclude the rental mortgage payment; it is calculated separately below.

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Years

If you are partway through a term, enter the years left until renewal.

Years

Enter the amortization remaining today, not the original amortization.

Estimated rental mortgage payment: $2,104.08/mo P&I. Total HELOC-funded rental outflow: $2,504.08/mo. Rent exceeds HELOC-funded outflow by $395.92/mo before HELOC interest.

Primary Residence

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Years

If you are partway through a term, enter the years left until renewal.

Years

Enter the amortization remaining today, not the original amortization.

Years

Applies after the next renewal and to each later renewal.

Estimated current primary payment: $2,893.11/mo P&I

HELOC

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Typically up to 65% of your home's value for the revolving portion (80% combined with your mortgage).

Tax Information

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Simulation

Years