Description
This air filter is made to a 40 x 32-1/4 x 1″ nominal size for HVAC systems, air handlers, and return grilles that require an exact custom dimension rather than a standard retail size.
Even a quarter-inch of gap around a filter can allow a significant percentage of return air to bypass the media entirely, which is why the exact fit matters as much as the filter’s efficiency rating.
MERV 13 targets the fine particulate fraction that lower MERV ratings allow through — including smoke, bacteria-carrying dust, and combustion byproducts. Airflow resistance is higher than MERV 8 or 11, so systems with borderline static pressure should be evaluated before switching up.
Specifications
- Nominal size: 40 x 32-1/4 x 1″
- Actual dimensions: 40 x 32-1/4 x 3/4″
- Efficiency rating: MERV 13
- Quantity: 12 filters per carton
Common applications for a 40 x 32-1/4 x 1″ custom filter include retrofit installations, legacy HVAC systems installed before standard sizes were codified, built-in return grilles that were framed to non-standard dimensions, and commercial unit housings that don’t match any current off-the-shelf size.
Features
- Pleated construction (or fiberglass, depending on MERV tier) designed for balanced capture and airflow
- Cardboard frame with reinforced media for structural stability during handling and installation
- Replace approximately every 90 days in standard installations; shorter intervals in high-dust, smoky, or heavy-use environments
- Orientation arrow printed on the frame to ensure correct airflow direction at install
Same 40 x 32-1/4 x 1″ size, different efficiency rating
| MERV 1-4Basic dust-stop | MERV 8Standard efficiency | MERV 11Enhanced efficiency |
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Need 40 x 32-1/4 x 2″ or another depth? This size is available in other depths we don’t stock online — reach out and our team will quote it for you, typically same business day.
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