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Timetable constraints
Configure hard and soft constraints for rooms, teachers, equipment, and curriculum rules.
Juho Isola, Smootables founder
Which timetable constraints should be hard versus soft when you configure a solver? Hard rules must hold: double bookings, missing qualifications, or curriculum gaps. Soft rules express preferences: spread lessons, avoid last period, or group workshops on the same days. Misclassified constraints are a top reason Untis and Excel workflows produce unusable drafts.
These guides explain how planners define constraint sets in Smootables, validate them before generation, and adjust weights when leadership priorities shift. They help you build a constraint model that matches how your school actually operates.
These guides cover planner process and decisions, not a Smootables product comparison. To evaluate capabilities, see automatic school timetabling software.
Guides in this topic
Select a guide below for process-focused depth on each step.
Hard constraints
The feasibility rules: clashes, required lessons, unavailability, the teaching day, and why an impossible set should say so.
Read guide →Soft constraints
Preferences with penalty costs: spread, gaps, compact days, and the weight tuning that makes trade-offs explainable.
Read guide →Room and equipment constraints
Specialist rooms as hard rules, capacity and equipment as limits, and the room data to model before the first run.
Read guide →Teacher availability
Hard unavailable periods, soft preferred free periods, and the part-time patterns that ricochet through a teaching team.
Read guide →Curriculum rules
Required periods, double periods, parallel blocks, and spread, sorted onto the hard-soft line before they reach the solver.
Read guide →
Related product pages
- Automatic school timetabling softwareConstraint-based timetable generation built into a structured planning workspace, with pre-solve validation, infeasibility reports, and full planner editing afterwards.
- AI powered school timetablingAn AI-powered planning and timetabling workspace where constraint-based generation produces feasible schedules and a planner assistant helps you explain, tune, and improve them without bypassing your rules.
See how Smootables fits your school
Book a walkthrough and we will map Smootables to your planning, workload, and timetabling process.