Sidewall HVAC Registers and Grilles

Sidewall Vent Covers, Supply Registers and Return Grilles

A sidewall vent cover is the face fitted over an HVAC duct opening in a wall, and it is either a supply register that pushes conditioned air into the room or a return grille that pulls room air back into the duct.

Wall openings are the most common place a vent gets replaced, and the choice comes down to three things in order: whether the opening blows or pulls, whether you need the air aimed, and whether the filter sits behind the face. Steel and aluminum both run through this range, and every unit is ordered by the duct opening.

Which Sidewall Vent Should You Order?

How Do You Size a Sidewall Vent?

Measure the duct opening in the wall, not the cover you are taking off. Sidewall units are listed width first, so a 14 by 6 and a 6 by 14 are different parts and are not interchangeable on a wall. The outer face runs about 2 inches larger than the opening in each direction, which lets the face overlap and hide the cut edge. Return air filter grilles overlap more than that: about 2-5/8 inches in steel and about 2-1/4 inches in the aluminum eggcrate style, because the frame has to hold the filter. On a return filter grille the listed size is the filter it takes, so a 20 by 20 filter grille holds a 20 by 20 filter. Step by step: how to measure a vent opening. To check airflow rather than fit, use the CFM sizer.

What Drives the Price of a Sidewall Vent?

Four things move the price inside this category: the material, the face size, whether the unit carries a damper or an adjustable core, and the face pattern. Steel and aluminum are priced differently at the same size, larger faces use more material, a damper adds parts, and eggcrate and bar faces are built differently from a stamped face. Current prices for every size sit on the product cards on this page.

Common Questions About Sidewall Vents

What is the difference between a sidewall supply register and a return grille?

A supply register sits over a duct that blows air into the room and usually carries blades, often with a damper to aim or close the flow. A return grille sits over a duct that pulls room air back to the system, so it has no damper and a more open face. If you hold a tissue to the opening and it is pushed away, it is a supply.

Is a 14 by 6 the same as a 6 by 14 on a wall?

No. Sidewall and ceiling units are listed width first, so the two sizes are different parts and the blades run the other way. Floor registers are the exception, because they drop into a flat opening and can be rotated.

Should a sidewall vent be steel or aluminum?

Steel resists dents and knocks in a hallway or a rental, and aluminum resists corrosion and weighs less, which is why bathrooms, laundries and coastal houses use it. The eggcrate, bar and linear slot faces on this page are aluminum.

Do sidewall return grilles need a damper?

No. A damper controls how much air leaves a supply duct, so it does nothing on a return. Return grilles here come with a plain or open face, and the filter models add a door instead of a damper.