What size duct board do I need for my ductwork?
Start with a full-sized sheet of duct board. Standard duct board comes in sheets that are typically 48 inches (120 cm) wide by 96 inches (240 cm) long. On one side of the sheet is a thick layer of fiberglass insulation. On the other is a thin foil backing which serves as the outside of the duct.
What is a duct board made of?
Duct board is an easy-to-work alternative to sheet metal for heating and cooling systems. It's made of fiberglass covered in a thin layer of aluminum and offers excellent thermal and acoustical benefits. The fiberglass keeps the air inside the duct work at a steady temperature, impervious to the temperature outside the duct work.
What tools do I need to measure for a duct board?
Tools required: Yardstick or tape measure, straightedge, orange(shiplap)or red (v-groove) tool, grey(femaleshiplap)tool, duct board knife, marking pen. 1. Determine board length as described above.
How to cut and join duct board?
How to Cut & Join Duct Board 1 Lay the duct board foil side down on a flat surface, either a table or a clean floor with plenty of room to work. 2 Mark the fiberglass side with lines for the panels, starting at the left edge and working to the right. 3 Create a rabbet joint on the left edge with a rabbet shiplap tool. ... More items...
How do you connect duct board?
1:367:00Intro to Fiber Glass Duct Board Fabrication (1/22) - YouTubeYouTubeStart of suggested clipEnd of suggested clipIt into a duct sort of like forming sheet metal in a break the longitudinal joint when stapled andMoreIt into a duct sort of like forming sheet metal in a break the longitudinal joint when stapled and taped in place is like a Pittsburgh joint in sheet metal.
What is duct board for?
Duct board is a semi-rigid fiberglass insulation material often used for residential or light commercial heating and cooling applications in lieu of metal duct.
How do you size a duct board?
Finished duct effective length is approximately 46” to 47” depending on board thickness, due to male and female shiplap ends. First, determine length of board required to make a duct of the desired size. This is twice inside duct height plus twice inside duct width plus stretch-out.
How do you bend a duct board?
2:519:48Fiber Glass Duct: Fabricating a 30° Offset (15/22) - YouTubeYouTubeStart of suggested clipEnd of suggested clipSo I can put that Bend right there and I can feel it go in and just shove it across keep the toolMoreSo I can put that Bend right there and I can feel it go in and just shove it across keep the tool down on the Ducks. So it'll cut always through the inch and a half board.
What is the R value of 1 inch duct board?
The 1-inch fibrous glass duct board has an R-value at 75°F of 4.3 h•ft2•°F/Btu. The 1½-inch board has an R-value of 6.5. The 2-inch board has an R-value of 8.7.
Can you use duct board outside?
Basically, the fiberglass absorbs moisture and provides a breeding ground for mold spores. Therefore, duct board should only be used where it will not be exposed to damp conditions.
What happens when you reduce duct size?
The key takeaway here is that air moves from a larger to a smaller duct, the velocity increases. When it moves from a smaller to a larger duct, the velocity decreases. In both cases, the flow rate — the amount of air moving through the duct, in cubic feet per minute — stays the same.
How do you use a duct board tool?
0:323:48Shiplap Tool shown for air duct insulation - YouTubeYouTubeStart of suggested clipEnd of suggested clipIt just gonna run your toe very gently across the length you duct. Work. Then you get to the end youMoreIt just gonna run your toe very gently across the length you duct. Work. Then you get to the end you just gonna turn it out and come straight up then take your duct work out.
What size duct should I use?
The size of the HVAC unit you'll need for the whole house can be found using the unit's average output and the square footage of your home. As a rule of thumb, you'll need 400 CFM of airflow per ton of air conditioning; it takes about 1 CFM of air to heat or cool 1 to 1.25 square feet of floor area.
How do you make a 90 degree angle with duct board?
1:4823:13How to make 90* elbow with Duct Board - YouTubeYouTubeStart of suggested clipEnd of suggested clipAnd you pivot until you get to 22 and a half degrees and you want it to be flush with the line outMoreAnd you pivot until you get to 22 and a half degrees and you want it to be flush with the line out here okay so that's pretty much 22 and a half degrees all right so you can easily mark.
How do you cut duct fiberboard?
0:1911:19Fiber Glass Duct - Hand Fab with Amcraft Tools (3/22) - YouTubeYouTubeStart of suggested clipEnd of suggested clipTool for the second third and fourth cut and the blue tool to make the fifth cut and form theMoreTool for the second third and fourth cut and the blue tool to make the fifth cut and form the stapling flap. We're going to groove a 12-8 duct with hand tools be using modified shiplap grooving.
What is the owl method?
If the offset distance is the O, the width of the duct W and its length L, the angle of the cut the installer needs to make to clear the obstacle can be determined by the following formula: O times W divided by L (O x W ÷ L). This calculation is usually referred to by the acronym OWL.
What is the static pressure of a duct system?
For heating and cooling air duct systems operating at velocities up to 5000 fpm, 250°F, 2" w.g. static pressure
How to bond tape to plastic?
If tape has been stored at temperatures below 50oF, recondition before use by placing in a warm environment (about 70oF) for at least 12 hours. Using suitable heating iron with plate otemperature set at 400°F (+25 F), pass iron once over bond area to achieve initial working tack. Quickly position tape on pre-heated area and press in place. Pass iron two or three times over taped area using rapid ironing motion. Complete bond by rubbing tape firmly with plastic squeegee.
Where are 2" cold rolled steel channels located?
2" cold rolled steel channels 22suspended from joists with #12 SWG galvanized steel hanger wire. Channels are located directly below the sheet metal duct liner, one on each side of the drop, spaced between drops 72" on centers for ducts up to 36" wide and 48" on centers for ducts between 36" and 60" wide. Refer to Underwriters Laboratories Fire Resistance Directory for complete assembly descriptions.
How many inches of duct board for a duct?
You’ll need to add a few extra inches to the width of each panel in order for them to align properly. 1 inch (2.5 cm) duct board will require an additional 1.75 inches ( 4.4 cm), 1.5 inches (3.8 cm) duct board will need 2.75 inches ( 7.0 cm), and 2 inches (5.1 cm) duct board calls for 3.75 inches (9.5 cm).
How thick is duct board?
Duct board is manufactured in three different thicknesses: 1 inch (2.5 cm), 1.5 inches (3.8 cm), and 2 inches (5.1 cm). The thickness of the board you use will be determined by the type of installation you’re performing.
How to cut shiplap with orange handle?
If you’re using an orange-handled duct knife to cut shiplap edges, you’ll need to turn the blade around the other way when making the second cut to allow the corner folds to fit into place properly. Remember to start each cut on the righthand side of the guide square to keep them consistent. ...
How to score fiberglass insulation?
Cut a 1.5 inches (3.8 cm) wide staple flap into the righthand edge of the board. Measure the board from the end with your guide square or a straight edge, then use a utility knife to score and remove the fiberglass insulation and create a loose flap. This section can later be fastened to the top of the folded duct to secure it.
How to cut duct board for HVAC?
To cut duct board for your next heating and air installation, you’ll use an L-shaped guide square and a sliding duct knife to score the sheet in multiple points along its length. This will allow it to be folded to specific dimensions to outfit your HVAC system with ducts that move air more efficiently, reduce noise, and prevent leaks and temperature loss.
Why do you need a guide square on a duct knife?
It will help guide the movement of the knife to ensure that every cut is straight and precise. It can help to use a guide square with some grip on the backside. That way, you won’t have to press down as hard to hold it in place or worry about it slipping as you move the duct knife along.
What is a red duct knife?
A red-handled duct knife slices a V-shaped groove into the insulation so that the individual sections can be folded neatly over on themselves with no wasted space at the corners. An orange-handled knife creates an interlocking “shiplap” edge.
What is duct board made of?
How to Cut & Join Duct Board. Duct board is an easy-to-work alternative to sheet metal for heating and cooling systems. It's made of fiberglass covered in a thin layer of aluminum and offers excellent thermal and acoustical benefits. The fiberglass keeps the air inside the duct work at a steady temperature, impervious to the temperature outside ...
How far from the edge of duct work do you staple?
Staple the flap to the left edge while holding the duct work 30 degrees beyond square. Staple every 2 inches, about 1/2 inch from the edge.
How to cut a rabbet joint?
To cut the joint, drag the rabbet shiplap tool along the edge of the board.
What is fiberglass ductwork?
The fiberglass keeps the air inside the duct work at a steady temperature, impervious to the temperature outside the duct work. The foil serves as a vapor barrier, as fiberglass can be damaged by moisture.
How to mark fiberglass panels?
Mark the fiberglass side with lines for the panels, starting at the left edge and working to the right. When you reach the right edge, mark a line for a stapling flap and the cut line for the right edge.
How to seal stapled joint?
Seal the edge you just stapled with pressure-sensitive aluminum foil tape. Or, reinforce the stapled joint with 3-inch-wide fiberglass mesh tape and cover it with mastic. Smooth the mastic with a putty knife and wear rubber gloves to protect your fingers.
