The publication you need to refer to is Pub 936 for Home Mortgage Interest Deduction. I am giving you a link below to that publication. Please refer to page 2 which describes a Qualified Home.
In order to have the interest on your RV loan tax deductible through the IRS, you must meet all qualifications. Due to the fact that the motorhome must be seen as a second home, it must be usable as an area in which one could be fully sustained, as in a regular home.
First and foremost, the RV must be used as security for the loan. There are certain interior requirements proving that home like accommodations are existing as well. These accommodations include a basic sleeping quarter, or sleeping area in the RV. The motorhome must also have a working toilet and certain cooking accommodations as well. Most RV's come pre-equipped with each of these amenities. If they are not pre-equipped, they are more than likely upgradeable to the status of qualified by simply adding the necessary accommodations.
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