Tech Drive TD-BF-04 Bathroom Exhaust Fan, 80 CFM, 1.5 Sones, 4-Inch Duct

Choosing a bathroom fan often comes down to balancing airflow with a quieter room. The Tech Drive TD-BF-04 is rated at 80 CFM and 1.5 sones, bringing together ventilation and low-noise operation for bathrooms up to 85 sq. ft.

Its 4-inch duct and ceiling-mounted design suit bathroom ventilation and moisture removal. The fan is Energy Star qualified and HVI and UL certified, with a galvanized sheet housing and plastic blades.

Need to replace a small bathroom fan without entering the attic? This model is designed for installation from the room side of the ceiling, making it a practical choice for certain retrofit projects.

Key points

An airflow capacity of 80 CFM helps move bathroom air, while the 1.5-sone noise rating supports a quieter everyday routine. That combination is useful when the fan runs during a shower or while the bathroom is in use. It is recommended for bathrooms up to 85 sq. ft. and can be used for air circulation, exhausting and ventilation.

The motor is brushless, and the unit operates at 19 watts. Energy Star qualification, along with HVI and UL certifications, provides useful reference points when choosing a bathroom exhaust fan. Buyers often highlight the quiet operation, airflow and ease of installation, and some also praise its ability to clear steam.

Fit and sizing

The fan measures 15.2D x 18.4W x 19.1H centimetres. Its housing is 7.5 x 7.25 x 6 inches, with a 4-inch duct, the ceiling opening is 7.6 x 7.3 inches. These measurements help when planning a replacement or checking the available ceiling space.

It is designed to replace most small standard bathroom fans using an existing opening, with installation carried out from the room side and no attic access needed. The housing is 6 inches high, so for a replacement where the existing housing is 4 inches high, make sure the ceiling has enough depth for the new unit. When installing over a bathtub or shower, it is acceptable for use on a GFCI-protected branch circuit.

Getting the most from it

Use the fan to exhaust air and help manage shower steam in an indoor bathroom within its recommended room size. For a straightforward planning check, compare the ceiling opening and housing depth with the existing setup, then confirm that the 4-inch duct suits the intended connection. Its low 1.5-sone rating is a relevant consideration for bathrooms close to bedrooms or other frequently used spaces.

Unlike a fan chosen primarily for a higher airflow rating, the TD-BF-04 pairs 80 CFM with a quiet-operation focus. That makes it worth considering when everyday noise matters alongside ventilation. The included components are screws, fan housing and user manual.

Final verdict

The Tech Drive TD-BF-04 is a practical fit for bathroom ventilation where a 4-inch duct, 80 CFM airflow and a 1.5-sone noise rating meet the project’s needs. Its room-side installation design can also help with suitable replacements where attic access is not available. For homeowners updating a small bathroom fan, the combination of measured fit details and quiet operation makes it a clearly specified option to consider.