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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
Rules the solver must never violate: one teacher in one room, required equipment, maximum class size. Explains when to lock a rule as non-negotiable.
Read guide →Soft constraints
Preferences the solver optimizes toward without blocking generation. Includes spread patterns, gap minimization, and department-specific targets.
Read guide →Room and equipment constraints
Tie lessons to labs, workshops, and shared kits with capacity limits. Covers specialist rooms that multiple subjects compete for.
Read guide →Teacher availability
Block unavailable periods, part-time days, and duties that remove teachers from teaching slots. Shows how availability differs from workload caps.
Read guide →Curriculum rules
Enforce subject frequency, double periods, and pathway requirements across the week. Includes rules vocational colleges use for mandatory practical hours.
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.