garage firewall question
 

i want to re do my firewall because the drywall near the floor is rotted out or missing sections and mice can get in. also they had a huge fan the has a huge opening into the attic to pull the hot air out. so none the less the wall is not completly sealed off for fire reasons but mice and gases getting into the house as well. what do i all need to do it proper and to code? 1/2 or 5/8" dryall?? also do i need plastic for a weather barrier? thanks

mice?

5/8 type x is what's most commonly used. Vapor barrier on the garage side is probably the wrong side but it depends on where you live.don't forget to address the issue that caused it to rot out in the first place

agree 5/8ths

Is that a mice or gasses trap? I'm confused.

If the drywall was installed tight to the floor there's the reason it failed.
It needed to be about 1/2" up off the concrete.
Mice will just eat right through and new drywall.
Need to address this mice problum.

agree, 5/8" type X fire rated gypsum board. If you cannot cover the holes that the mice are getting in try packing them with steel wool (and throw a few moth balls in the holes, mice hate them).

im trying to find my camera to show you what i have going on, i mean itl be real easy to re do. i just want to make sure i re do it right and to code.

the 1st pic you can see that huge fan. so i have the huge hole in the wall for the fan that is useless. the 2nd pic is along the floor behind the stairs. that is pretty much how it is the whole way along the floor.

ok i am getting ready to tear down that wall and take that fan out as well. i know i need 5/8'' fire rated drywall and fire resistant drywall tape. if insolation is good i will leave it unless mice got to it. few questions though..

1. should i leave the drywall 1/2" off the concrete floor? i want it to fire and gas tight as well as no mice getting back in.

2. should i just drywall to the studed wall or should i put some vapor barrier if the interior wall doesnt have any?

either way the new wall will be alot better than what i have now. alot gaps, all exposed seams and the huge hole in the wall for that fan

1. You don't want the drywall to touch the floor. 1/2" is good....

2. The vapor barrier needs to be on the inside. You do NOT want to add a vapor barrier on the garage side.

ok thanks. do i really need a vapor barrier if there is not one. i have no idea if they have one or not, im guessing now as i see how alot of thing were done around here.

also what is the difference with a vapor barrier on the inside vs garage side?

i want to add a outlet and the one i have is not grounded so i want to run a whole new line from the breaker box. do i need any special fire rated boxes and or wires? im guessing they should be at least in a conduit

From the 2009 IRC.

Andy.

thanks, there is no vapor barrier on interior wall. just drywall on each side of the studded wall with insolation. the garage side has that backer board stuff then the drywall though. i will be tearing that out, was that just for extra protection from fire because the drywall currently is only 1/2"?

The backer board stuff was probably for shear resistance. If you tear that out, you need to replace it. 3/8 or 1/2 plywood or 1/2 OSB depending on the age of the home.