Resource leveling is used to smooth fluctuations in production during projects to avoid downtime or inconsistencies in schedules for hourly workers. Resource limited scheduling is a specific approach to implementing a resource leveling strategy in project management. Resource limiting becomes necessary when you must spread out work -- and do so with limited resources.
Over the course of a project, you will have times when employees are busier and when materials are more readily available for production. The primary purpose of a product manager's use of resource leveling is to smooth out production slowdowns and speedups. If a project is estimated to last a month, for instance, a leveling process helps ensure that staffing and material usage are consistent each day for the duration.
Leveling benefits both the company and workers. It ensures that all labor hours are paid for actual time that employees and materials are in production. You can also base project duration estimates on project tasks being performed throughout a given worker's eight-hour shift. Hourly employees also prefer consistency and predictability in schedules. If you send an employee home after two hours one day and ask him to stay 10 or 12 hours the next, it can create stress and low morale.
Resource limited scheduling, sometimes called allocation leveling, is a specific approach to resource leveling. This particular approach is necessary when your goal is to smooth out or optimize daily production when materials are limited during the course of a project. If a company only has enough materials to produce a certain number of widgets in a given month, for instance, the project manager must figure out the best way to schedule employees and production of those widgets during the month.
When scheduling with limited resources, you typically have to make preference decisions. This is a big difference from resource leveling when you have access to unlimited materials. Project managers must figure out which jobs in a given period are most critical because of profitability or deadlines. They then allocate resources to those most preferred jobs. Additionally, the managers may schedule employees to work on different jobs using different materials each day to ensure stability in labor production even when certain materials are in limited supply.