Public school employers say contract demands tabled by the B.C. Teachers Federation (BCTF) would cost the system nearly $2.2 billion more each year.
The demands include doubling the provision for bereavement leave to provide 10 days paid leave on the death of any friend or relative.
The union also wants teachers to be able to take 26 weeks off each year as a fully paid leave of absence to provide compassionate care to any person as well as wage parity with other provinces, although it hasn't yet tabled an exact pay hike demand.
Teachers salaries range from around $47,000 to over $75,000 a year.
Salary parity would mean a 21 per cent raise for most teachers to match levels in Alberta and cost an estimated $618 million, according to the BC Public School Employers Association (BCPSEA).
Other top cost drivers in the proposals include extra prep time at $417 million and $445 million for a retirement bonus that would give departing teachers an extra five per cent pay out for every year they've worked.
Unionized teachers voted 90 per cent in favour of strike action last month. Any initial job action starting in September is expected to be limited to paring back administrative work and other non-teaching activities.