I am interested if anyone has any experience in setting up cafeteria plans in the construction industry where an hourly employee's work may be intermittent becuase of slow periods and layoffs. It seems that calculating salary deductions can be a sticking point for employers because insurance premiums often become due at the beginning of a month, and an employee might be laid off after the first 2 or 3 days in a month, and the employer cannot recoup the premium already paid.

Any thoughts would be greatly appreciated.

Try an Hour Bank Medical Plan. These use a base hours worked per week to pay for the next periods insurance and the "excess" hours are "banked" to accumulate for periods of layoffs or work stoppage. I dont know what state you are in so I cant give you an agent referral.