Home insurance replacement cost with no appraisal

I’m in the process of shopping for home insurance now that I’m in contract.

My loaner waived appraisal. The house listing doesn’t include the sqft of house (apparently it’s common in that area). But I do have floor plans.

Should I just do the math on the floor plan and use that total sqft to calculate replacement cost?

Insurers are asking for total living space and some aren’t accepting the floor plan…