Trimming a Piece of Drywall

[Prashun Patel]

+n on the utility knife.

Also, if you have any ragged edges, you can always use a (gasp alert) beater 4-1 rasp/file to smooth out the edges of the paper and rock.

[Robert Engel]

I'm sure its code. Why else would anyone want to wrestle 5/8 on a ceiling?

I think 5/8 is fire code I've seen it used between garage and house.
Never seen is used on ceilings in my area.
I've also seen it used for soundproofing.

[George Bokros]

I believe 5/8 is used on ceilings when the trusses are on 24" centers to prevent sag. My trusses are on 24" centers.

[Malcolm McLeod]

Other areas may be different, but here at least UBC (code) calls for 5/8" gypsum between any living areas and attached garage (due to higher fire risk in the garage). If there was no living area above the garage, you could previously use 1/2" on ceiling or non-adjoining walls. The adjoining wall(s) was(were) often covered with double layer of 1/2" (to save ordering 2 different types of drywall).

Now it is uniform 5/8" on all garage surfaces (plus fire rated door to a living area). Joist spacing makes no difference.

George, this may be a non-issue, but consider how any potential (non-code?) replacement will be viewed by home inspector if you have re-sale plans. A piece of drywall might not be a deal-breaker, but it would be a PITA.

[Rick Potter]

My entire house is 5/8" It is a tract house, with no code or construction reason to have it. One of these days I am going to ask neighbors who have worked on their house if theirs is the same. I would not be surprised if 5/8 was
sent to the site by mistake, and they used it.

I suppose it could have been a selling feature.......quiet rooms, more strength, etc. It has been a pain replacing doors inside. We ordered pre-hung doors for 5/8 drywall, but they all came with jambs that had to be made wider anyway, and we had to set them to one side flush and add to the jambs on the other. We have continued using it in the remodel and additions, including the shop.

[Malcolm McLeod]

My entire house is 5/8" ...

But you're in CA. Land of rock n' roll. And I mean 'land', not music. Could it be earthquake zone code?? 5/8" will give slightly better racking resistance to walls.

Me? I like my TX dirt to stay where I put it.

[Chris Padilla]

I dunno...1/2" on my walls and 5/8" on my ceilings here in rockin' Bay Area.

[Malcolm McLeod]

All this for trimming a piece of drywall? ...screws could result in explosion? Mud & tape could actually melt the internet.

[Matt Day]

1/2" drywall is not rated for fire, each sheet of 5/8" gives a 30 minute rating, assuming the assembly is installed properly.

[Prashun Patel]

I just gotta say:

"Trimming a Piece of Drywall" got 30 responses (well, 31 now) and 500 views.

What
is
the
world
coming
to??!?!?!?!

[Bill McNiel]

5/8" GWB is used for 24" C/C spans and 1 hour fire separations. 1/2" for 16" C/C spans.

Use a Surfoam plane for cleaning up GWB edges. There is a one handed version about the size of a block plane. Handy, cheap tool to have around.