How To Measure Floor Vent Size

Most vent faceplates are large enough to support the register and cover the entire hole.

How to measure floor vent size.

Measure the duct opening in your floor wall or ceiling. For sizing please use the duct size and reference the overall frame size for installation. Take out the existing floor register and measure the length width of the opening in inches all registers will be listed in inches. Remove screws holding the vent in place.

Note if the register or grille you are replacing is for a wall ceiling or floor. For example a 4 x 10 flush mount wood register has an overall size of 6 x 12. If your duct work opening in the floor is 4 x 10 you ll need to purchase a 4 10 floor register. However the overall size of the opening must be considered.

Measure the size of the air duct opening. Pull the vent forward and out of the opening. The flush mount no frame is also ordered by measuring the duct size. Then measure the length and width of the air duct opening.

Locate the register or grille you are replacing and note if it is for a wall ceiling or floor. Length in inches by height in inches this is your duct opening size. To measure your register properly remove the existing register from the floor wall or ceiling in which it is installed. This means that floor registers will often be smaller number first like 4 10 or 4 12.

Measure the opening in your floor wall or ceiling. You could also use a 4 x10 floor register if your hole measured 4 1 4 x 10 1 2. A register is measured by the size of its louvers which is the bottom of the register that fits into the ventilation duct. The width and length of your opening should match the duct opening sizes.

Remove the screws that hold the vent in place. The length l is always expressed first followed by the height h dimension. Many of our vent grilles include directional patterns so it is crucial to provide both dimensions in their respective order.