You cannot deduct the amount of interest from line 16 as mortgage interest on houses. If you have not used any of the proceeds of a mortgage included in line 12 of the worksheet for transactions, investments or other deductible activities, all interest is on line 16. Personal interest is not deductible. If a divorce or separation agreement requires you, your spouse or former spouse to pay mortgage interest on a house that both of you own, the interest payment may be child support. See the discussion on payments for jointly owned housing under Alimenty à Pub. 504, divorced or separated. If you refinance with a new lender, even in the year of the new refinancing, undepreciated points are deductible from a previous refinancing. Also remember that at the time of the 2018 renewal, the hypothetical insured will incur losses of US$200,000, which will be awarded in 2017. The coverage requirement for the 2017 insurance year is now US$1 million minus US$200,000 $US, or $US 800,000. For the 2018 insurance year, the loss is set at $1.2 million. The total amount of coverage needed is therefore the remaining $800,000 from 2017, plus the new $1.2 million $US for the 2018 insurance year or $US 2 million.
This is called collateral stacking. However, it is important to note that the use of stacked security is not separated by year.