Where to find non-standard size air filters?
Uncommon or fractional dimensions like 19-7/8" x 21-1/2" x 1" are not marked on the filter and cannot be found at standard home improvement stores like Home Depot. This leaves homeowners buying a new house struggling to figure out where they can source or afford these specific sizes.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
Found another way around this?
Share your steps and trade-offs so fellow engineers don't have to reinvent the wheel. No account required.
- 1Searching for places to make custom-sized filters or trying to use standard sizes.Did this help you?
- 2Searching for online retailers to find lower pricesDid this help you?
- 3Considering replacing the entire custom filter box setup with a standard 4-inch filter systemDid this help you?
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“Where can I get these filters in Texas?! Cheapest options?”source ↗
“Bought this house & learning as I go.”source ↗
“The size was not marked on the outside, so I took the filter out and it says 19-7/8” x 21–1/2” x 1”. So that’s not something I’m going to find at Home Depot.”source ↗
Where this came up
People with this problem also raised
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