Working Hours Act does not mention five-day working week. However, the regulations concerning weekly rest periods and Sunday work impose real limits on how weekly working hours are placed on different days of the week. 

Our collective agreements are based on five-day working week. However, in regular weekly working time, periodical work or shift work the working week can be longer than five days, provided that the working time is adjusted so that it corresponds to regular working time. This is done by issuing several consecutive days off in exchange. 

The working week begins usually on Mondays, unless agreed locally otherwise. Work day begins usually when the day changes or on a point of time normally followed in the company (such as the beginning of the first shift). These regulations can matter when calculating weekly or daily overtime. 

All changes concerning the beginning and end of regular working hours must be negotiated in cooperation with the personnel. 

Average working hours mean that the regular daily and weekly working hours may vary according to a given roster and within the limits set by the collective agreement. 

When average working hours are applied, a roster has to be made for the adjustment period, during which the working time is adjusted to the average weekly hours. The roster should include the times when daily work begins and ends, the length and placement of daily rest period and weekly days off. 

Average working hour can be applied by the decision of the employer or upon local agreement. In case the employer decides unilaterally to apply average working hours, the daily working time cannot be more than 8 hours. According to the most of the collective agreements the working hours must be adjusted to 37.5 or 40 hours per week by the following way:

• Maximum 6 week period in day work.
• Maximum 9 week period in shift work comprised of two shifts
• Maximum one year period in shift work comprised of three shifts. 

In these cases the adjustment period should include on average two days off per week 

Even though the collective agreements allow for local agreements on average working hours, the regular daily work cannot exceed 12 hours. 

Regulations on average working hours differ in collective agreements so check your own collective agreement before agreeing on them with your employer. You also can contact us.