Exposed Wall

John_Elm · November 14, 2013, 7:34am

Quick question. Home is 2003 over 3000 square feet. My question is I know the garage is required to be sealed mud/taped with 1 hour fire rated drywall. There is one wall inside the garage that is a outside wall and is not associated with the living space. Now the ceiling attached to this wall has living space above. All areas in the garage is covered with fire rated drywall. Shouldn’t this area be as well?

mlarson · November 14, 2013, 1:35pm

Your local AHJ is the one to ask.

Note: this is a corrected post to remove wrong information.

See post below for my area.

wmisegades · November 16, 2013, 3:50pm

Mike, you’d have the ceiling drywalled but not the wall supporting the ceiling?

jjonas · November 16, 2013, 5:19pm

Bill, I don’t like it either, but it is the way it is. I always recommend it be covered with type X, but it is not required (as least in any area I serve). Many areas do not require the tape/mud as long as the edges fall on a stud.

mlarson · November 16, 2013, 5:54pm

I am wrong. thanks for your comment.

jjonas · November 16, 2013, 8:01pm

That is for WI, Mike. How do you handle MN?

mlarson · November 16, 2013, 9:48pm

I don’t site code. EVER

wmisegades · November 16, 2013, 10:03pm

Further more

IRC 2006:
R309.2 Separation Required
The garage shall be separated from the residence and its attic area by not less than ½-inch (12.7 mm) gypsum board applied to the garage side. Garages beneath habitable rooms shall be separated from all habitable rooms above by not less than 5/8-inch (15.9 mm) Type X gypsum board or equivalent. Where the separation is a floor-ceiling assembly, the structure supporting the separation shall also be protected by not less than ½-inch (12.7 mm) gypsum board or equivalent. Garages located less than 3 feet (914 mm) from a dwelling unit on the same lot shall be protected with not less than 1/2–inch (12.7 mm) gypsum board applied to the interior side of exterior walls that are within this area. Openings in these walls shall be regulated by Section 309.1. This provision does not apply to garage walls that are perpendicular to the adjacent dwelling unit wall.

and

IRC 2009 and 2012:
…]R302.6 Dwelling/garage fire separation. The garage shall
be separated as required by Table R302.6. Openings in
garage walls shall comply with Section R302.5. This provision
does not apply to garage walls that are perpendicular to
the adjacent dwelling unit wall.
Commentary: Numerous potential hazards exist within garages
because occupants of dwelling units tend to store a
variety of hazardous materials there. Along with this
and the potential for CO build-up within the garage,
the code requires that the garage be separated from
the dwelling unit and attic as indicated in Table
R302.6. Garage walls and ceilings that do not form a
separation from the dwelling unit are not required to
be rated unless they are an extension of a rated
assembly.
TABLE R302.6. See page 3-53.
Commentary: This table specifies when and how the garage must
be separated from the dwelling unit and any attic
space. Walls between the residence and the attached
garage, or ceilings between the garage and an attic
space, must have at least 1/2-inch (12.7 mm) gypsum
board on the garage side. If a habitable room is
above the garage, the ceiling must be at least 5/8-inch
(15.9 mm) Type X gypsum board on the garage side.
Additionally, the exterior walls of the garage are
required to have 1/2-inch (12.7 mm) gypsum board on
the interior face where they support floors separating
all or part of a dwelling unit above the garage.