RUF Duct
Double wall, foam-filled duct for outdoor use that’s fully watertight, weighs less than insulated duct, and combines ducting and insulation in one step
Learn about the RUF duct specs
Dive into the RUF duct’s typical physical properties, guages for both Rectangular and Spiral RUF duct builds, a step-by-step walkthrough of the field connection, and testing information.
Construction Highlights
- A double wall duct intended for outdoor use.
- Watertight, weighs less than insulated duct, combines ducting and insulation in one step.
- The only product made that is shop foamed in place leaving no air gaps.
- Outerwall is more rigid due to adhered foam and less subject to material handling issues.
- Foam is stable from -40° Fahrenheit to 200° Fahrenheit.
- Made in several shapes such as round, rectangular, and flat oval.
- Wall thicknesses abailable in 1″, 2″, and 3″ options.
- Material options include Galvanized, Stainless Steel, Aluminum, and Powder Coated.
- All pieces are numbered for ease of installation.
- Assembly is very easy with very few parts to deal with.
RUF Duct construction meets and has been tested to comply with UL Fire & Smoke Standards (UL-723 & ASTM E-84). Rectangular duct tested to 7″ negative static — no deflection.
Foam system Description
23-008M HFO is a two component, Opteon 1100 blown, all PMDI based low density pour-in-place rigid urethane foam system. 23-008M HFO has a high R-Value, premium cure and demold properties.
Meets ASTM E-84: FS<25, SD<450 at 4″ thickness; FS<25, SD>200 at 1″ thickness
R-Values Per Inch: 1″=6.45; 2″=12.9; 3″= 19.35
TYPICAL PHYSICAL PROPERTIES
| PROPERTY | TEST METHOD | VALUE |
|---|---|---|
| Core Density |
ASTM D-1622 |
2.5 pcf |
| Tensile Strength |
ASTM D-1623 |
58 psi |
| Moisture Vapor Transimssion |
ASTM E-96 |
2-3 perm-In |
| k-Factor (aged in metal panel) |
ASTM C-518 |
0.155 Btu-in/ (hr-ft² F) |
Gauges
RECTANGULAR RUF DUCT
Both inner and outer walls are constructed out of materials desired:
Galvanized, Stainless Steel, Aluminum, and Powder Coated.
| LARGEST DIMENSION | INNER WALL | OUTER WALL |
|---|---|---|
| 0-20" | 24 Ga. | 24 Ga. |
| 21-30" | 22 Ga. | 22 Ga. |
| 31-42" | 20 Ga. | 22 Ga. |
| 43-60" | 20 Ga. | 22 Ga. |
| 61-80" | 18 Ga. | 20 Ga. |
Spiral RUF DUCT
Both inner and outer walls are constructed out of materials desired:
Galvanized, Stainless Steel, Aluminum, and Powder Coated.
| DIAMETER | INNER WALL | OUTER WALL |
|---|---|---|
| 0-20" | 24 Ga. | .032" |
| 21-30" | 22 Ga. | .040" |
| 31-42" | 20 Ga. | .040" |
| 43-60" | 20 Ga. | .040" |
| 61-80" | 18 Ga. | .050" |
| 81-96" | 18 Ga. | .050" |
ROOF CONNECTION
Field Connection
STEP 1: Start gasket from outer seam as shown.
Completed Step 1
STEP2: Prepare second piece by caulking any lapped metal as shown.
Completed Step 2
STEP 3: After putting pieces together, clamp evenly around perimeter to prepare for fasteners.
STEP 4: Evenly space fasteners at a minimum of 4″ centers. If TDF joints are used, boltcorners and apply clips as a minimum of 6″ spacing.
Testimonials
RUF duct install has been an efficient process from site delivery to install. When roof supports are laid out and installed accurately, the RUF duct system can easily be pre-assembled in part on the ground and set in place via crane or Lull.
We think it’s a great product. It’s quality made, very easy to install, and extremely durable. We try to sell it to design teams whenever the opportunity presents itself. We’ve ordered both aluminum and galvanized construction and have had great success with each.