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.

The flush mount no frame is also ordered by measuring the duct size. For floor registers they follow the same rules as return grilles where you state the dimension parallel to the louvers first. If your hole measures 3 7 8 x 9 7 8 you should be able to use a 4 x 10 floor register depending on the style. Remove screws holding the vent in place.

Measure the opening in your floor wall or ceiling. Then measure the length and width of the air duct opening. Pull the vent forward and out of the opening. To measure your register properly remove the existing register from the floor wall or ceiling in which it is installed.

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

Measure the size of the air duct opening. Take out the existing floor register and measure the length width of the opening in inches all registers will be listed in inches. However the overall size of the opening must be considered. If your duct work opening in the floor is 4 x 10 you ll need to purchase a 4 10 floor register.

Remove the screws that hold the vent in place. For example a 4 x 10 flush mount wood register has an overall size of 6 x 12. You could also use a 4 x10 floor register if your hole measured 4 1 4 x 10 1 2. How to measure and replace a floor register.

Note if the register or grille you are replacing is for a wall ceiling or floor. A register is measured by the size of its louvers which is the bottom of the register that fits into the ventilation duct. For sizing please use the duct size and reference the overall frame size for installation.