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M Kelekci
07-22-2007, 10:07 PM
Is the garage (attached) ceiling supposed to be insulated in the attic?

Thanks,

Bruce Breedlove
07-22-2007, 10:37 PM
Yes, if it is a heated garage. If the garage is not heated then it really doesn't matter if it is insulated or not.

M Kelekci
07-22-2007, 10:40 PM
Yes, if it is a heated garage. If the garage is not heated then it really doesn't matter if it is insulated or not.

Thanks for the post.
No, it is not a heated/air conditioned garage.

wayne soper
07-23-2007, 07:02 AM
So not requied. But the side wall against the living area must be , as well as fire rated.

Jerry Peck
07-23-2007, 07:16 AM
as well as fire rated.

Nope. Not "fire rated".

"Separated", which simply means ... 1/2" gypsum board on the garage side.

wayne soper
07-23-2007, 08:06 AM
Jerry, in my area there must be a 5/8 sheetrock wall, minimal, between the living area and the garage. That is fire rated,No?

M Kelekci
07-23-2007, 08:33 AM
Nope. Not "fire rated".

"Separated", which simply means ... 1/2" gypsum board on the garage side.

We still need the fire rated door between the house and garage though, don't we?

Jerry Peck
07-23-2007, 10:37 AM
Jerry, in my area there must be a 5/8 sheetrock wall, minimal, between the living area and the garage. That is fire rated,No?

No.

You would need 5/8" Type X on both sides, screws spacing as required, sealant around the edges, continuity taking priority over any other walls intersecting with it, etc., to be a fire rated 'fire wall' or 'fire partition'.

Simply installing 5/8" Type X on one side does not, to anything I've seen so far, make it a "fire rated wall".

Thus, to answer Matt's question below, no, a fire rated door is not required (of course, there may be a local code which requires a fire rated door, which would be a 20 minute rated door).

Wayne,

Does that apply to two story houses with living space above the attic, or to all dwelling units, including one story ones?

There are additional requirements I did not state above for when there is living space above the garage.

Jim Luttrall
07-23-2007, 11:11 AM
Thus, to answer Matt's question below, no, a fire rated door is not required (of course, there may be a local code which requires a fire rated door, which would be a 20 minute rated door).



As Jerry mentioned, your local code will prevail, but the IRC
requires a solid wood door min. 13/8" thick, solid or honeycomb steel doors of the same thickness, or a 20 minute fire-rated door.

Also requires 1/2" gypsum on the garage side and 5/8" type X with habitable rooms above.

Note the IRC does not require a fire separation wall as Jerry is referring to, just "separation" but the intent is clear.
This is all in IRC 2003 section R309

M Kelekci
07-23-2007, 03:27 PM
As Jerry mentioned, your local code will prevail, but the IRC
requires a solid wood door min.

Do you mean to say if I inspect a house in City of Houston which adapted IRC, 1 3/8" thick, solid or honeycomb steel doors of the same thickness, or a 20 minute fire-rated door is required. However if house is located in another jurisdiction that has not adapted IRC and doesn't have any requirement for the garage/dwelling seperation, the same door is not a repair item to write up.


Thanks for these great posts. You guys are so helpful.

Jim Robinson
07-23-2007, 03:38 PM
I write it up regardless of where I'm inspecting. It's a good idea to have a fire separation door between the garage and the house. Whether it is required or not doesn't change my opinion of why I write it. If they ask (which is almost never) I will tell them that it may not be required, but I still think it is a good idea. I've never had a problem with that explanation, which is the same for smoke alarms, GFCI's, and other safety things that change over time.

Jim Luttrall
07-23-2007, 04:30 PM
Code varies by jurisdiction, but stupid knows no limits.
I use the IRC as a starting place since it is the fall back code for the state on new construction warranties and is a pretty good bet on being accepted by most. Besides, I can't be an expert on all the codes and variations that are within 5 miles of my house, much less for the entire state.

As has been repeated here many times, code is the minimum. I will often recommend something that is not "code", but it is a good starting place.

As far as your specific question about a door, there may well be a more stringent requirement or no requirement at all, but I will write up a hollow core door or one with a window every time, code or not.

Jerry Peck
07-23-2007, 05:13 PM
What time zone is this forum on? Apparently I posted this at 11:08 pm! It's only 4:08 where I am.

I believe you can set the time zone in your preferences.

Jim Luttrall
07-23-2007, 06:46 PM
Has anybody noticed any more or less ceiling drywall cracks in insulated garage ceilings vs. uninsulated in unheated garages?
No, humidity is one real killer on dry wall joints and is where I usually see cracks.
Lots of builders don't paint garage interiors and that seems to have much more impact than insulation.