HVAC Permit requirements across Washington
By Mario Bailey Last verified 2026-06-17
Requirements and size thresholds for hvac permits vary by locality. The table below compares what each Washington county or city requires. Always confirm with the local office before starting.
What to know about hvac permits in Washington
HVAC permits in Virginia typically apply to new installations and to replacing gas or oil fueled equipment. Costs vary with equipment type and your locality. Using a licensed mechanical contractor matters, because the install must meet code and pass inspection, which also helps protect your equipment warranty.
| Locality | Permit required? | Typical threshold |
|---|---|---|
| Bellevue | Yes | Not specified |
| King County | Yes | Not specified |
| Seattle | Yes | Not specified |
| Tacoma | Yes | Not specified |