Fire rated ceiling code

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morocco

New member
I have a customer that has a condo with fire rated ceiling double 5/8" drywall. They want to add ceiling lights in 3 bedrooms with 4 outlet boxes in the master & 2 in each of the other 2 bedrooms. I want to install steel octagon boxes mounted to the double 5/8" drywall & install a surface mount LED fixture to each 4" steel octagon box that is 2 1/8" deep. Am I able to do this? Also, some boxes will occupy the same joist space.

Thank you very much for your time

Don Defilippo
 

mgookin

Senior Member
Location
Fort Myers, FL
If you compromise the rated assembly, you need to add rated assembly to maintain the required rating.

If those steel boxes are flush mounted and not surface mounted, you can probably use some 3M putty pads.

You didn't say how many stories this building is. If just a few stories, you probably just need one hour.

If high rise, go to the building dept and do it right because that could be 2hr, 3hr, etc...

In addition to the double 5/8" gyp, what else is there? A concrete deck, wooden truss joists, etc.?
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
For starters the electrical outlet box cannot be supported solely by the drywall, it must be fastened to a framing member.
 

LIM

Member
Location
NC
Infinity is correct. Also, if you are installing a steel box that is less than 16sqin, you most likely do not need to do anything additional if the ceiling rating is 2hr or less.
 

mwm1752

Senior Member
Location
Aspen, Colo
Infinity is correct. Also, if you are installing a steel box that is less than 16sqin, you most likely do not need to do anything additional if the ceiling rating is 2hr or less.

I recall steel boxes have a 1.5 hr rating so in a 2 hr assembly additional protection is required to comply with rating--- 2009 IBC code for a general reference
713.3.2 Membrane penetrations. Membrane penetrations shall comply with Section 713.3.1. Where walls or partitions are required to have a fire-resistance rating, recessed fixtures shall be installed such that the required fire-resistance will not be reduced.
Exceptions:
1. Membrane penetrations of maximum 2-hour fire-resistance-rated walls and partitions by steel electrical boxes that do not exceed 16 square
inches (0.0103 m2) in area, provided the aggregate area of the openings through the membrane does not exceed 100 square inches (0.0645 m2) in any
100 square feet (9.29 m2) ofwall area. The annular space between the wall membrane and the box shall not exceed l/S inch (3.1 mm). Such boxes on
opposite sides ofthe wall or partition shall be separated by one of the following:
1.1. By a horizontal distance of not less than 24 inches (610 mm) where the wall or partition is constructed with individual noncommunicating stud cavities;
1.2. Bya horizontal distance of not less than the depth ofthe wall cavity where the wall cavity is filled with cellulose loose-fill, rockwool or slag mineral wool insulation;
1.3. By solid fireblocking in accordance with Section 717.2.1;
1.4. By protecting both outlet boxes with listed putty pads; or 1.5. By other listed materials and methods.
2. Membrane penetrations by listed electrical boxes of any material, provided such boxes have been tested for use in fire-resistance-rated assemblies
and are installed in accordance with the instructions included in the listing. The annular space between the wall membrane and the box shall not
exceed l/S inch (3.1 mm) unless listed otherwise. Such boxes on opposite sides of the wall or partition shall be separated by one of the following:
2.1. By the horizontal distance specified in the listing of the electrical boxes;
2.2. By solid fireblocking in accordance with Section 717.2.1;
2.3. By protecting both boxes with listed putty pads; or
2.4. By other listed materials and methods.
3. Membrane penetrations by electrical boxes of any size or type, which have been listed as part of a wall opening protective material system for use in fire-resistance-rated assemblies and are installed in accordance with the instructions included in the listing.
4. Membrane penetrations by boxes other than electrical boxes, provided such penetrating items and the annular space between the wall membrane and the box, are protected by an approved membrane penetration firestop system installed as tested in accordance with ASTM E 814 or UL 1479, with a minimum positive pressure differential of 0.01 inch (2.49 Pa) of water, and shall have an F and T rating of not less than the required fire-resistance rating of the wall penetrated and be installed in accordance with their listing.
5. The annular space created by the
 

roger

Moderator
Staff member
Location
Fl
Occupation
Retired Electrician
I recall steel boxes have a 1.5 hr rating so in a 2 hr assembly additional protection is required to comply with rating---
Actually metallic boxes are listed for use in up to 2 hr walls without additional protection (unless they are back to back or closer than 24" to each other) Non metallic boxes used in 2 hr walls are individually marked for use in 2 hr walls.

Click here for a quick reference.


Roger
 

LIM

Member
Location
NC
I recall steel boxes have a 1.5 hr rating so in a 2 hr assembly additional protection is required to comply with rating--- 2009 IBC code for a general reference
713.3.2 Membrane penetrations. Membrane penetrations shall comply with Section 713.3.1. Where walls or partitions are required to have a fire-resistance rating, recessed fixtures shall be installed such that the required fire-resistance will not be reduced.
Exceptions:
1. Membrane penetrations of maximum 2-hour fire-resistance-rated walls and partitions by steel electrical boxes that do not exceed 16 square
inches (0.0103 m2) in area, provided the aggregate area of the openings through the membrane does not exceed 100 square inches (0.0645 m2) in any
100 square feet (9.29 m2) ofwall area. The annular space between the wall membrane and the box shall not exceed l/S inch (3.1 mm). Such boxes on
opposite sides ofthe wall or partition shall be separated by one of the following:
1.1. By a horizontal distance of not less than 24 inches (610 mm) where the wall or partition is constructed with individual noncommunicating stud cavities;
1.2. Bya horizontal distance of not less than the depth ofthe wall cavity where the wall cavity is filled with cellulose loose-fill, rockwool or slag mineral wool insulation;
1.3. By solid fireblocking in accordance with Section 717.2.1;
1.4. By protecting both outlet boxes with listed putty pads; or 1.5. By other listed materials and methods.
2. Membrane penetrations by listed electrical boxes of any material, provided such boxes have been tested for use in fire-resistance-rated assemblies
and are installed in accordance with the instructions included in the listing. The annular space between the wall membrane and the box shall not
exceed l/S inch (3.1 mm) unless listed otherwise. Such boxes on opposite sides of the wall or partition shall be separated by one of the following:
2.1. By the horizontal distance specified in the listing of the electrical boxes;
2.2. By solid fireblocking in accordance with Section 717.2.1;
2.3. By protecting both boxes with listed putty pads; or
2.4. By other listed materials and methods.
3. Membrane penetrations by electrical boxes of any size or type, which have been listed as part of a wall opening protective material system for use in fire-resistance-rated assemblies and are installed in accordance with the instructions included in the listing.
4. Membrane penetrations by boxes other than electrical boxes, provided such penetrating items and the annular space between the wall membrane and the box, are protected by an approved membrane penetration firestop system installed as tested in accordance with ASTM E 814 or UL 1479, with a minimum positive pressure differential of 0.01 inch (2.49 Pa) of water, and shall have an F and T rating of not less than the required fire-resistance rating of the wall penetrated and be installed in accordance with their listing.
5. The annular space created by the

You are in the wrong Section of code....:happyno::slaphead:

713.4.1.2 Membrane penetrations. Penetrations of membranes that are part of a horizontal assembly shall comply with Section 713.4.1.1.1 or 713.4.1.1.2. Where floor/ceiling assemblies are required to have a fire-resistance rating, recessed fixtures shall be installed such that the required fire resistance will not be reduced.

Exceptions:

1. Membrane penetrations by steel, ferrous or copper conduits, pipes, tubes or vents, or concrete or masonry items where the annular space is protected either in accordance with Section 713.4.1.1 or to prevent the free passage of flame and the products of combustion. The aggregate area of the openings through the membrane shall not exceed 100 square inches (64 500 mm2) in any 100 square feet (9.3 m2) of ceiling area in assemblies tested without penetrations. 2. Ceiling membrane penetrations of maximum 2-hour horizontal assemblies by steel electrical boxes that do not exceed 16 square inches (10 323 mm2) in area, provided the aggregate area of such penetrations does not exceed 100 square inches (44 500 mm2) in any 100 square feet (9.29 m2) of ceiling area, and the annular space between the ceiling membrane and the box does not exceed 1/8 inch (3.2 mm).
3. Membrane penetrations by electrical boxes of any size or type, which have been listed as part of an opening protective material system for use in horizontal assemblies and are installed in accordance with the instructions included in the listing. 4. Membrane penetrations by listed electrical boxes of any material, provided such boxes have been tested for use in fire-resistance-rated assemblies and are installed in accordance with the instructions included in the listing. The annular space between the ceiling membrane and the box shall not exceed 1/8 inch (3.2 mm) unless listed otherwise. 5. The annular space created by the penetration of a fire sprinkler, provided it is covered by a metal escutcheon plate.
 

mwm1752

Senior Member
Location
Aspen, Colo
You are in the wrong Section of code....:happyno::slaphead:

713.4.1.2 Membrane penetrations. Penetrations of membranes that are part of a horizontal assembly shall comply with Section 713.4.1.1.1 or 713.4.1.1.2. Where floor/ceiling assemblies are required to have a fire-resistance rating, recessed fixtures shall be installed such that the required fire resistance will not be reduced.

Exceptions:

1. Membrane penetrations by steel, ferrous or copper conduits, pipes, tubes or vents, or concrete or masonry items where the annular space is protected either in accordance with Section 713.4.1.1 or to prevent the free passage of flame and the products of combustion. The aggregate area of the openings through the membrane shall not exceed 100 square inches (64 500 mm2) in any 100 square feet (9.3 m2) of ceiling area in assemblies tested without penetrations. 2. Ceiling membrane penetrations of maximum 2-hour horizontal assemblies by steel electrical boxes that do not exceed 16 square inches (10 323 mm2) in area, provided the aggregate area of such penetrations does not exceed 100 square inches (44 500 mm2) in any 100 square feet (9.29 m2) of ceiling area, and the annular space between the ceiling membrane and the box does not exceed 1/8 inch (3.2 mm).
3. Membrane penetrations by electrical boxes of any size or type, which have been listed as part of an opening protective material system for use in horizontal assemblies and are installed in accordance with the instructions included in the listing. 4. Membrane penetrations by listed electrical boxes of any material, provided such boxes have been tested for use in fire-resistance-rated assemblies and are installed in accordance with the instructions included in the listing. The annular space between the ceiling membrane and the box shall not exceed 1/8 inch (3.2 mm) unless listed otherwise. 5. The annular space created by the penetration of a fire sprinkler, provided it is covered by a metal escutcheon plate.

Did I not comment " General reference " the requirement is the same
 

mwm1752

Senior Member
Location
Aspen, Colo
Actually metallic boxes are listed for use in up to 2 hr walls without additional protection (unless they are back to back or closer than 24" to each other) Non metallic boxes used in 2 hr walls are individually marked for use in 2 hr walls.

Click here for a quick reference.


Roger

Thanks, Ul approves so do I --
 

LIM

Member
Location
NC
Did I not comment " General reference " the requirement is the same

My point was to reply to your thought that you needed additional protection in a 2hr ceiling when you do not. The code you posted was for walls not ceilings.
 

north star

Senior Member
Location
inside Area 51
= ( ~ ) =


morroco,

If the existing fire rated ceiling will be altered, you should
contact the AHJ for their guidance.......Be sure to have a
complete Scope of Work to provide to them.

They may require something very detailed, and they may
not.........Coverest Thy Arse and seek their input ! :happyyes:



= ( ~ ) =
 

cowboyjwc

Moderator
Staff member
Location
Simi Valley, CA
a plastic box is actually rated for two hours, and a metal box needs no other protection as stated before.

What you do have to watch is the listing of the box when using a plastic box. Inside the box it will be marked with any combination of F, W, C. F=Floor W=Wall C=Ceiling.

Can lights of course are not rated and would require a rated cover. There are several types of these, but most are going to require extensive drywall repair, but then again so would the can lights as you can not use old work cans. Boxes must be secured to the structure.
 
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