Where to find nonstandard size HVAC vent registers
Standard store-bought vent registers often do not match older or awkwardly sized HVAC openings like 14x10 inches, leaving homeowners unable to find direct replacements. This mismatch forces people to search for specialized trim products to fill gaps or custom-sized grilles that standard retailers do not stock.
What the numbers show
Counted from the threads quoted below. How we count
- The most recent one is from October 2026.
- This comes up 18.0× more often in r/HomeMaintenance than across the site as a whole.
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.
- 1Ordering the correct custom size onlineDid this help you?
- 2Avoiding the use of smart registers on return ventsDid this help you?
- 3Drilling new holes in plaster to fit slightly different standard sizesDid this help you?
- 4Ordering parts online when local big box stores do not have them in stockDid this help you?
- 5Using alternative dimensions like 12x6 covers with no dampersDid this help you?
- 6Buying large sheets of corrugated plastic, modifying or cutting them to fit, and attaching them to siding or using zip-tiesDid this help you?
- 7Using thin PVC sheets cut to sizeDid this help you?
- 8Clean and paint the old coverDid this help you?
- 9Have the original cover sandblasted and rechromedDid this help you?
- 10Go to a commercial HVAC supplier instead of big box storesDid this help you?
- 11Order custom-sized grillesDid this help you?
- 12Search online specialty stores for alternative patternsDid 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.
“When it rains heavily, we've seen water start to pool in these window wells.”source ↗
“They are an odd shape, so when we first moved in, we couldn't find any well cover that fit. Do you know where we could get some non-standard shaped covers?”source ↗
“I have an old school duct that’s 10” x 8” and I can’t find a duct cover for it.”source ↗
“Mine looks so shabby and I’d like to replace it.”source ↗
“I dont see replacements this size with that exact simple pattern.”source ↗
“It’s not so much the size as it is the screw holes. Idk if you can see in the pic but the screws holes are literally at the edges of the duct.”source ↗
“Replacing my HVAC vent registers but one of the vent openings is too large for register... are there trim products I can use to fill the gap?”source ↗
“There is one room where the vent opening is an awkward size: 14 x 10”source ↗
“The closest size I can find for the new registers is 10 x 10.”source ↗
“one thing we've discovered is that the HVAC ducts don't quite match up with modern standard sizes and we're having a hard time finding replacements - the registers and grilles have been painted at least 5 or 6 times and the louvers aren't quite working right anymore.”source ↗
“We were able to find supply registers that fit, but we're having some issues finding return grilles that would work.”source ↗