Measuring home ownership rate for all adults

Census appears to assign the tenure to adults who are not household heads (ie, their pernum is 2 or higher) as the same as their household’s head. As a result, adults living with their parents (who own) are tabulated as ownershp of 1 (“owned or being bought”). This results in an artificially elevated homeownership rate. What’s the best way to calculate the ownership rate for all adults?