"Dadoing" Drywall

[Chris Padilla]

So I need to replace a chunk of ceiling drywall (hence 5/8") and I've discovered the framers did a lousy job with setting a header within the joists about 1/4" too low so it produces a decent bow to the drywall that I'd like to fix.

My idea is to "dado" or "gouge out" or "excavate" some drywall from the backside so that the drywall fits a bit more flush. Yes, I'm quite anal.

Some ideas I had:

(1) Use my good old PC690 (may need a subbase to extend its reach...the header is 3 2x6s) and a crappy bit and route away. Should make a nice cloud of "drywall smoke" so I would do this at the end of my driveway so the entire neighborhood can enjoy it with me.

(2) Slice 'n dice up the area with a razor blade to remove the paper packing, then gouge away with something. I have this hunky glue scraper with a carbide tip brazed to the end that I've used in the past on operations like this but they were over much smaller areas than 3 2x6s about 3' long. This sounds like a long process to me.

That is about it for easy ways to do this. Anyone else have any other brilliant ideas? Fixing the header is out of the question...not going there so drywall is it.

Cheers!

[Prashun Patel]

Can you add blocking to the sides of the ceiling beam and then run 5/8 dwall TO the beam, and then 1/4 dwall under the beam? Taping and feathering that section might be easier and more stable than dadoing through the paper?

[Travis Gauger]

Can you get away with 1/2" rock and then shim other areas? Problem with sheet rock is when you take that back paper off it gets real weak in that spot. I had a similar issue in a long hallway where I wanted to run my 10' sheets perpendicular to the joists. One joist was proud by about 1/4" than all the rest. I ran my first sheet a stock 5/8". the next piece was 1/2" and shimmed on the joists that were correct. On the joist that was proud, it was sheet rock to joist with no shim. Worked alright for me. Good luck.

[Steve Clardy]

Razor knife and an old chisel

[Chris Padilla]

Can you add blocking to the sides of the ceiling beam and then run 5/8 dwall TO the beam, and then 1/4 dwall under the beam? Taping and feathering that section might be easier and more stable than dadoing through the paper?

Interesting idea but I'm not sure I've seen 1/4" drywall at the borg...maybe I just need to look more closely.

[Chris Padilla]

Can you get away with 1/2" rock and then shim other areas? Problem with sheet rock is when you take that back paper off it gets real weak in that spot. I had a similar issue in a long hallway where I wanted to run my 10' sheets perpendicular to the joists. One joist was proud by about 1/4" than all the rest. I ran my first sheet a stock 5/8". the next piece was 1/2" and shimmed on the joists that were correct. On the joist that was proud, it was sheet rock to joist with no shim. Worked alright for me. Good luck.

Hmmm, you have me thinking now. I could just cut out the area where the header is and then put in some 1/4" drywall...assuming I can locate some. I suppose 1/4" wonderboard could work, too.

I wonder about the weakness I'll introduce with my initial idea...I would plan to screw it to the header so it should be supported.

My job is patchwork where I cut out a 4' wide section by whatever length to get all the damaged drywall out (water) and get a clean install of a new piece.

[Chris Padilla]

Razor knife and an old chisel

Can do on that one! I already started in that direction before thinking, "Crap, this will take FOREVER!"

Thanks, Bro...Ma would be proud!

[Lee Koepke]

Shawns idea was pretty good.

the only other way is to plane the proud header, or add some blocking for a few joists on either side to ease the transition

[Prashun Patel]

If u can't come by 1/4" dwall, can you use (don't laugh) 1/4" plywood? I believe drywall compound will stick well enough to it. After the whole thing's skimmed with compound, who'd be able to tell the diff?

Alternatively, have you thought about just leaving 5/8" on the beam and feathering out compound like 20" on both sides? I bet no passersby'd be able to detect the diff...

[Chris Padilla]

If u can't come by 1/4" dwall, can you use (don't laugh) 1/4" plywood? I believe drywall compound will stick well enough to it. After the whole thing's skimmed with compound, who'd be able to tell the diff?

Alternatively, have you thought about just leaving 5/8" on the beam and feathering out compound like 20" on both sides? I bet no passersby'd be able to detect the diff...

Well, in all honesty, I didn't know about the sag BEFORE the damage occured but NOW that I know about it, it will seriously drive me batty! I at least need to TRY and do something about it and then I'll feel better about the results.

[Prashun Patel]

I've had professional drywallers in to fix my hanging and mudding mistakes in the past. In all 3 instances, they reached for a bucket and long taping knives first. It's amazing what you can solve by properly feathering.

Yr gonna have to feather a new patch anyway. If it were me, I'd fight this battle with a sword instead of a bazooka. If it still sucks, you can always sand it away and patch as per orig plan.

[Heather Thompson]

Chris,

I feel your pain, my husband hates it when I discover something is not quite right and then tear it apart to fix the issue. Last year I replaced the sliding patio door and tore out the nasty old carpet, found that the cable guy caused a leak above the old door. I ended up tearing out the dry wall above the door to check the condition of the header, ended up being good, one thing lead to another and I removed all of the dry wall on the south wall. I then went to replace it and found that the studs were way out at one end of the room, found shims at the BORG (1 1/2"x1/16"x3') that worked great. when it comes to mudding, thats when I call Matt, he is a pro and well worth the money.

Heather

Well, in all honesty, I didn't know about the sag BEFORE the damage occured but NOW that I know about it, it will seriously drive me batty! I at least need to TRY and do something about it and then I'll feel better about the results.

[Chris Padilla]

Thanks, Heather. I needed to read that. My wife thinks I'm completely nuts going to "agonizing" length on such things....

She's right, of course!

I've got a guy mudding/taping my living room right now; I should have a chat with him about this spot....

[Lee Koepke]

and Chris remember, the tolerances for drywall are measured in 1/4" not .001

(framing is about 1/2" these days )

[Jim Becker]

Cut it out manually.

BTW, for specialty items like 1/4" and 3/8" rock...you need to go to a "real" sheetrock supplier. The 'borg isn't going to have anything like that in most cases.