The Rust Decay Calculator is an essential tool for players of the survival game Rust, helping you determine how long your structures and vehicles will last before they decay completely. Understanding decay mechanics is crucial for base planning, resource management, and ensuring your hard-earned builds don't disappear while you're offline.
In Rust, all player-made structures gradually deteriorate over time when not maintained through a Tool Cupboard. This decay system prevents server clutter and encourages active gameplay. Our calculator provides precise decay time estimates based on material type and current health percentage, allowing you to plan maintenance schedules and prioritize repairs.
Understanding Rust Decay Mechanics
Decay in Rust is a fundamental game mechanism that slowly reduces the health of unmaintained structures. The decay rate depends on two primary factors:
- Material Type: Different building materials have different base decay times at 100% health
- Current Health: Structures with lower health decay proportionally faster
Material Decay Times (100% Health)
- Twig: 1 hour - Weakest material, used for temporary structures
- Wood: 3 hours - Common early-game material, moderate durability
- Stone: 5 hours - Mid-game material, good balance of cost and durability
- Sheet Metal: 8 hours - Late-game material, high durability
- Armoured: 12 hours - Strongest material, maximum decay resistance
How Decay Works
Rust uses a decay tick system to calculate structure deterioration. By default, the server checks for decay every 300 seconds (5 minutes). During each tick, structures without Tool Cupboard protection lose health based on their material type and current condition.
Decay Time (hours) = Base Decay Time × (Current Health % ÷ 100)
Example: A wood structure at 50% health will decay in 1.5 hours (3 hours × 0.5), not the full 3 hours.
Preventing Decay with Tool Cupboards
The Tool Cupboard (TC) is the primary method of preventing decay in Rust. When placed and stocked with appropriate materials, it prevents all structures within its radius from decaying.
How to Use Tool Cupboards:
- Craft and place a Tool Cupboard inside your base
- Authorize yourself by pressing 'E' on the cupboard
- Fill it with the same materials your structures are made of
- The cupboard will automatically consume materials to prevent decay
Material Consumption Rates
Tool Cupboards consume materials at different rates depending on what they're protecting:
- Wood: ~10 wood per wall per day
- Stone: ~10 stone per wall per day
- Metal Fragments: ~20 metal per wall per day
- High Quality Metal: ~2 HQM per wall per day (armoured)
Vehicle Decay
Vehicles in Rust also decay when left unattended. Common vehicle decay times:
- Minicopter: ~3 hours at 100% health (outdoors)
- Scrap Heli: ~3 hours at 100% health
- Cars: ~8 hours at 100% health
- Boats: ~3 hours at 100% health
Storing vehicles in a garage with Tool Cupboard protection prevents decay.
Repairing Structures
Before structures fully decay, you can repair them to restore health:
- Equip a Building Plan (blueprint)
- Look at the damaged structure
- Hold the repair button (default: right-click)
- Provide the required materials from your inventory
Repair costs are proportional to the damage. A structure at 50% health requires 50% of its original building cost to fully repair.
Server Settings Impact
Server administrators can modify decay rates through the decaytickrate setting:
- Default: 300 seconds (5 minutes per tick)
- Slower Decay: Higher values (e.g., 600 = 10 minutes per tick)
- Faster Decay: Lower values (e.g., 150 = 2.5 minutes per tick)
- No Decay: Some servers disable decay entirely
Note: This calculator assumes the default setting of 300. Check your server's settings for accurate calculations.
Strategic Considerations
- Upgrade Priority: Upgrade external walls and foundations first, as they're most vulnerable to decay
- Material Choice: Balance cost vs. decay time. Stone offers good value for mid-game bases
- Multiple TCs: Large bases may need multiple Tool Cupboards for full coverage
- Offline Protection: Ensure TC is fully stocked before logging off for extended periods
- Raid Defense: Higher-tier materials not only resist decay but also provide better raid protection
Common Mistakes
- Empty Tool Cupboard: TC must be stocked to prevent decay
- Wrong Materials: TC needs the same material type as your structures
- TC Not Authorized: You must authorize on the TC for it to work
- TC Out of Range: Structures beyond TC radius will decay
- Ignoring Low Health: Damaged structures decay faster - repair them promptly