If so, your supply ducts may be on inside walls. x 10 in.

Place the jack studs on both sides of the insulated ductwork, leaving a small gap between the insulation and the jack studs.

Building codes are as varied as the state and county agencies who write them, so be sure to check with your local building inspector’s office before doing duct work yourself, only to learn it all has to be torn out and replaced by a licensed installer.

Should HVAC Return Duct Be the Same Size? To perform the calculation, you need to know how much insulation is in your exterior walls, how much is in your attic, the size and type of glazing for each window, the type of construction of each window, extra special lights or cooking appliances that generate heat, compass direction that each wall of your house faces, etc. If the supply ducts are in the floor, then the return air should be located up high. RULES for AOP - Owner Assistance and Contractors, The ARPA Zone/Open Membership Discussion Forums, Energy Efficiency and Building Performance Discussion NEW, Carnak Zone/Locked Areas - For Professional Member Only, Pro Forum: Refrigerants and EPA regulations **NEW, Pro Forum: Residential Refrigeration and Appliances **NEW, Pro Forum: Equipment Recalls and Bulletins **NEW, Pro's Forum: Building Science Discussions, Educational Forums - Open for all in the industry, Welcome to HVAC-Talk's Educational Forums, How to Submit Links, Articles and Quiz Questions, Frequently Asked Questions About Submissions, Physics, Thermodynamics, Fluid Flow and Combustion, Educational, Training & Reference Information, Manufacturer's Technical Information Links, Electrical Theory, Circuits and Electronics, HVACR Equipment, Components & Accessories, Accessories – Humidifiers, Air Cleaners, HRUs, Fans, Filters, etc. Can it be sacrificed for the cooling cause? Buy a monster 5-ton central unit? Framing lumber the same dimension as the wall studs. The single giant return air grill in the floor balances the load at the furnace motor but does nothing to promote cross-ventilation in each room. Expert Note: If you had no return air in your room, you would create a positive pressure. Extend the lowest and highest mark around the stud with the carpenter's square and pencil.

That would then reduce the flow of conditioned air to that space. After you install the duct through the studs, you will need to add framing around the top and bottom of the ductwork to allow for a wall finish such as drywall. It has a special snap lock built in at the factory. 2012 IECC Secure both ends with a few 1/2" sheet metal screws through the collar. Repeat the process for the top header, aligning the top edge of the header with the high pencil mark. For a better experience, please enable JavaScript in your browser before proceeding.

x 3 ft. Half Section Rectangular Stack Duct Master Flow's Rectangular Stack Duct is used Master Flow's Rectangular Stack Duct is used for HVAC system applications between wall studs as supply and return ducts, and to vent range hoods, kitchen and bath fans between walls as well . Much better than chopping up the structure and it will work better too.

Maybe you have upgraded your windows or insulation. If you encounter framing members, move the location either way so the hole is between the members. However, there are two rooms that I never place return air ducts - kitchens and baths. For walls, make vertical cuts at each side of the grill opening, staring at the bottom edges of the opening and continuing to the ceiling. Copyright 2018 Tim Carter. We respect your email privacy. Place a mark on the floor in front of the wall that you need to run the ductwork through, measuring from the same wall that you used for the centerline of the duct.

The return air ducts help pull the air as it is being pushed. This stuff can be complicated. What are the shipping options for stack ducts? To explain the components of a forced air system: a fan draws air from the house into the system through return air vents (Image 1).

Use non-insulated, flexible ducting to connect the two returns (Image 4).

Align the bottom of the lower header with the low line you transferred to the studs in Step 8.

By creating an account you agree to the Hunker. All other ducts in unconditioned spaces or outside the building envelope are insulated to at least R-6. Cut the straps to length with sheet metal cutters. Transfer the height of the ductwork to the stud that you marked in Step 4. Dampers are critical for the efficiency of a forced air system. Set up a reciprocating saw with the appropriate blade for the wood paneling or drywall finish. On an older existing home that is being retrofitted for central air-conditioning, they are a must. The takeoff rotates to make it easier to fit the duct into place. For example, measure 7 inches from both sides of the centerline for a 12-inch wide duct. Yes, if your house is either hot or cold, I'll bet you have inferior or lacking return air ducts. Seal the connection with duct tape. You need to use a round duct cutter because the cutter actually removes a thin strip of metal along the cut line (Image 2), which makes the cut a lot smoother. Improve your home’s heating efficiency and save money by installing a new programmable thermostat. Do you have a laundry chute that you don't use that often? Insert the square end of the rigid duct into the opening from above.

You may have a single giant return air grill on the floor or at the bottom of a staircase. Here's an example of a giant return air grill near the floor. JavaScript is disabled. You achieve the highest comfort when the air conditioner removes as much humidity as possible from your interior air.

Center it between the joist and screw into place with self-tapping screws. Don't hesitate to contact me if I can help. This may be at the ceiling or on the face of another wall. Measure up from the mark you placed on the stud in Step 6 and place another pencil mark at the height of the duct. Once you know how many BTUs your house is gaining, you can purchase the correct sized air conditioner. Components – Coils, Heaters, Motors, etc. A good hardwood installer can make the repair and no one will be the wiser. An HVAC return air can be in the floor, but they work much better on walls up about 7 feet. If you put in a unit that is too powerful (produces too much cooling), it will short cycle. The duct with the least resistance is a round duct. From each mark place another mark 2 3/4 of an inch up from the top mark and down from the bottom mark.

Seal and secure the connection to the existing duct with duct tape. Gain access to our free AOP (Ask a Professional) Section to get real answers for your questions. Rease , based in Texas, has been a professional construction and outdoor writer since 2003. I'm adding duct work in my house, and I've been told that I can just run the ducts up the walls and into the bedrooms on the second floor. Getting heating and cooling to work from the same ducts is hard. Learn how to replace rotting ductwork and install a new return vent. Hunker may earn compensation through affiliate links in this story. Install a new section of flex duct, if necessary, to complete the run to the rigid duct. 2009 IRC. What is the top-selling stack ducts product?

These ducts terminate at grills on the ceiling or walls in a room. Drywall that is nailed to 2x4s is really a duct - a box with 4 sides. Thanks so much! So you really want your house cold.

I wish you luck in your effort to stay cool. It is a question you must ask the installer. Compare the marks on the floor with the wall studs. If it is not, the outdoor unit will struggle to keep your house cool. Get video instructions about kitchens, bathrooms, remodeling, flooring, painting and more. It's much better to put a return-air duct in each room. They come in various, different sizes. Do you just cut out an entire section of the 2x4? When posting in forums, letting us know your location will help others give better feedback/advice/solutions to your questions. Snap the duct together.

First, building codes in many areas require that the cold air return line gets external insulation, and therefore you will need to leave a gap for the insulation around the duct … Think about it. Put a brace plate on it afterward. Run the ductwork through the opening you created in-between the studs. The hot air goes up into the plenum and from there flows to the supply trunk line (Image 3) where it is distributed through vents throughout the rest of the home. The veins and arteries supplying blood to the different parts of your body, even out to your fingers and toes, are the same size as the veins and arteries returning that blood back to your heart. Lose a little living space and make a chase for the duct. In other words, you must determine how fast heat is getting into your house and what things inside the house are contributing to heat gain. For you to achieve the published efficiency and performance that is sold to you by the salesperson, the interior coil housed in the furnace must be compatible and matched for size!

Note: Use a power nut driver to drive self-tapping sheet metal screws. You do what we do in new homes. Running a metal cold air return duct between studs requires knowledge of both HVAC systems and the components involved in framing. These step-by-step instructions show how to install a radiant-heat system and tile floor. These ducts terminate at grills on the ceiling or walls in a room.

Helping You to Do It Yourself! Have to get the air back to the furnace. We have used these with tremendous success. The reason for return air is simple. Don't miss your favorite shows in real time online. You will be cool and clammy.

Running duct work and all other heating and air conditioning-related jobs are regulated by the local building codes and the HVAC industry. These can be drywalled easily. Add a couple of support brackets to help support the weight of the duct. Install dampers at the registers to adjust airflow. In some cases, when knocking down a wall, the ducts can be temporarily abandoned during the work. Align the lower portion of the cut stud with the pencil mark on the bottom header and drive two 8-penny nails through the header and into the stud to secure the cut stud to the header. Remove the section of wall finish with a nail bar and a hammer. What are you going to do? Well I suppose that if you've never done it you just dobn't know but a standard size stack ducting comes in 3 1/2 inch and 2 1/2 inch sizes.It comes in 10",,12",,and 14" withs.On internal walls you always use the 3 1/2" stack and external walls you use 2 1/2 " stack so you can get at least 1" of insulation in. Removing the grill is all that’s necessay prior to demolishing the lower section of the wall.