Return air grille considerations
The function of a cold air return is to facilitate a large amount of airflow back to the furnace. Consquently, an overly restrictive faceplate design is anathema to proper hvac functioning. Many common commercially available air returns only have about 50% open area. The majority of our return air vent designs are way better than that, in addition to being pleasingly stylish.
Every once in a while someone asks us to put a damper, or airflow regulator on a cold air return. That is a very bad idea. At the very least this will cause the system to work in an unpredictable manner, but it is also a possibility that significant damage to the system may occur. Don't do it!
For unknown reasons, many an air return grille duct opening was made a non-standard size. So a big box store won't be the place to locate this. But many of our wood and metal styles are able to be customized to fit these unusual sized openings. In fact, not too long ago we made custom cast bronze air returns for the vintage California governor's mansion, which was built in the late 1800's. They apparently didn't have standard sizing at that time period.
An air return usually has a lip or flange around all four sides. The width varies, but on average the dimension is usually around one inch. But they can be less or more. When shopping for a return vent cover you'll want to see how much room you have for the lip. If there is limited space, such as half and inch, this can usually be accomodated. But of course we need to know in advance what the situation is, so you'll want to have some measurements handy when you call in to discuss. Another good idea is to take pictures so you can email them to use if a clarification of the situation is needed.
Often a wall duct opening is located down at the level of the floor. In this case there are several different methods of dealing with the situation. This is often called a sidewall return. You'll definitely want to call in for advice. Sometimes a person's duct opening is both on the wall and floor. Usually this is seen with a vintage charmer house or commercial building. A decorative return air grille will need to be configured to work and install in this situation correctly.
Return air grille sizes can be baffling. If you don't see the size you need on our site be sure and call us since with many styles we fabricate them to fit whatever your oddball situation requires. This even includes fractional sizes.
A cold air return that we supply can be made of cast metal, sheet metal, standard or exotic wood, or cast paintable resin. There is a lot to the subject so talking things through on the phone is a much better idea than trying to order online. We take care to make sure everything is configured correctly.