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Frequently Asked Questions
Can I purchase your products online?
No, our residential electrical boxes and specialty products are not available for purchase online.
Where can I buy your products?
Our products are available through a large network of distributors across the United States. Find your nearest stocking distributor here.
Is your catalog available online?
How do I download Spec Sheets for each product?
Spec sheets for each of our products can be downloaded in PDF form.
- Navigate for your desired part number
- Click the blue “View PDF” button located next to the part number on the product detail page
- Save or print the PDF for future reference
Who is my local Representative?
You can find your local representative by entering your zip code here.
Reduced in Horizontal Box Separation in Fire Resistive Wall & Ceiling Assemblies
In what type of construction would this rating apply?
This rating applies where nonmetallic sheathed cable is used and walls are constructed of wood and non-load-bearing steel studs and gypsum.
Can all boxes marked with a 2-hour wall rating be installed in the same manner?
No. A box that is marked with 2-hour wall rating means that you can install the box in a 2-hour fire resistive wall or walls with less than 2-hour rating. To find out details of the installation, you must read the instructions found in the UL® Fire Resistive Directory or from the UL® card provided by the manufacturer. The Directory/UL® card describes the following:
- Those boxes suitable for use in the wall by basic model number
- The maximum size opening in square inches
- The maximum openings in total square inches per 100 square feet
- The maximum clearance around the box
- The type construction of the wall assembly – “wood studs and gypsum”
- The wall designs such as “U-300 Series” meaning all wall designs found in the UL Fire Resistive Directory from U-301 through U-370, including those staggered stud designs and separated wall designs
- Horizontal separation when mounted on opposite sides of the wall h. Cover plate material (when limited)
What is the maximum size box that can go into the same stud cavity?
Paragraph #2 of the card states for those fire resistive wall designs with or without insulation, the maximum size box is a 3 gang 3300, 3303, 9313 (22.0 sq. in.). These boxes can be mounted in all U-300 Series walls with a horizontal separation of three inches when boxes are mounted on opposite sides of the wall. Note: This does include staggered stud construction.
Does this rating apply to staggered stud configuration?
Yes. U-300 Series walls have both staggered stud designs in addition to separated type walls.
Will I still need to use mineral wool or fiberglass insulation?
The wall assembly design dictates the need for insulation. The wall design does not change when penetrated by Allied Moulded outlet boxes.
What if I am actually putting double drywall in the middle to help with sound?
If the wall is constructed of wood studs and gypsum board and is a 2-hour or less fire resistive rated, the penetration with an Allied Moulded outlet box will not cause the wall to be derated as long as it is installed according to instructions.
Can I put the boxes back to back?
The Fire Resistive card says the boxes must be separated by three inches horizontal separation but not back to back.
Do you still have to caulk the knockouts that are penetrated by the wire?
Boxes were tested with nonmetallic sheathed cable installed. No caulk is necessary where knockouts are penetrated by the nonmetallic sheathed cable.
If I accidentally open a knockout I do not need, do I need to caulk it?
The National Electrical Code requires all unused open knockouts to be closed. Allied Moulded’s Speed “K” Klamp™ is an accepted means of closing the knockout (documentation available upon request). Open, unused knockouts in boxes without Speed “K” Klamps would need to be closed.
Is there a rating that relates to vertical separation?
No, not at this time.
Does this apply to ceiling configurations also?
The instructions for ceiling penetrations are found on the same documentation as the wall boxes; however, the instructions are different.
Does this apply to low voltage devices?
The fire resistive rating is for Allied Moulded boxes penetrating fire resistive walls classified at 2 hours or less. What is placed inside the box is covered by the National Electrical Code and does not affect the fire resistive rating of the box.
Which inspector will be enforcing this code? Electrical or Building or Fire?
Minimum horizontal box separation is a requirement of the applicable building code. Generally, the electrical inspector will view the installation first, but final compliance falls on the building inspector.
Are all of your electrical box products fire rated?
Most of our electrical box products are fire rated. Consult the specific product detail page or contact one of our Customer Service Specialists for more information.
Is there literature available online for your products?
Yes! Literature is available for each of our products and can be found here.
