Residential Building Inspector B1Building Planning and Life SafetyEasy
A residential building inspector is reviewing plans for a new single-family dwelling. The plans indicate the installation of a new clothes dryer. What is the maximum allowable length for a straight rigid metal exhaust duct for this appliance?
- A20 feet
- B25 feet
- C30 feet
- D35 feet
Show answer & explanationAnswer & explanation
Correct answer: D. 35 feet
The IRC specifies the maximum length for dryer exhaust ducts to ensure proper ventilation and prevent fire hazards. For a straight rigid metal exhaust duct, the maximum length is 35 feet.
Why the other options are wrong
- A. This is less than the maximum allowable length.
- B. This is less than the maximum allowable length.
- C. This is less than the maximum allowable length.
Dryer Exhaust Duct Length
The maximum allowable length for a clothes dryer exhaust duct to ensure efficient operation and fire safety.
- Rigid metal ducts are preferred.
- Length reductions apply for elbows.
- Ensures proper airflow and prevents lint buildup.
Memory trick: Dryer ducts need to be just right, not too short, not too tight, and definitely not too long, to keep lint from going wrong.