Houston HVAC Permit

What's Required in Houston

• A mechanical permit is required for any HVAC unit replacement (A/C, furnace, or boiler).
• Proper secondary drain pan and safety float switches must be installed for attic units.
• Manual J load calculations required for new system sizing to ensure energy efficiency.
• Condenser units must be anchored to a level pad and meet property line setbacks.
• Replacement of identical gas lines or ductwork alterations also require mechanical permits.
• Must be performed by a State of Texas licensed Mechanical/AC contractor.

Do You Need a Permit to Replace an AC or Furnace in Houston?

Yes. Houston treats HVAC replacement as permit-required work, and that includes the common case people hope is exempt: a like-for-like swap of a furnace, AC condenser, or heat pump in the same location. Permit fees typically run $76–$250, and the permit is issued by the Houston Permitting Center. In practice your HVAC contractor pulls it as part of the job — if a bid doesn't mention the permit, ask why, because unpermitted mechanical work surfaces at home sale time and in insurance claims.

HVAC Repairs vs. Replacement: Where the Permit Line Falls

The line falls at equipment, not maintenance. Repairs that keep an existing system running — a blower motor, capacitor, control board, or a thermostat swap on existing wiring — generally don't need a permit. Replacing the equipment itself, adding or reworking ductwork, or running new gas or electrical almost always does. Refrigerant-line and coil replacements sit in the gray zone and vary by city. When the scope is unclear, describe the exact job to the Houston Permitting Center before work starts; it's a five-minute call.

How to Get a HVAC Permit in Houston

Frequently Asked Questions