When hanging drywall... horizontal or vertical on walls?

[5mall5nail5]

Hey guys - this might be preference, but when hanging drywall, say a wall that's 16' long 10' high, do you guys go with 48" x 10' panels and go vertical? Or, do you go 48" x 8' (or 10') and go horizontal? I have a bunch of outlets to account for, so either way I need a lot of detail cuts, but I am just curious what the rationale is and if there's a method.

Thanks,
Jon

Edit: Also, this weekend will be my first attempt at drywall work. I have a ton of tools but nothing specific to drywall. What materials and tools should I expect to pick up? Any recommendations?

 

[nolimits76]

Normal practice is to run vertical with the studs. However, I have seen some guys run horizontal seams in order to minimize waste, etc.

 

[Stevie-Ray]

I'll be drywalling my garage this winter as well. I've come to the conclusion that I will be hanging my 4X8 panels vertically. Reason is, it will be a long, drawn out process with the panels hung without mud for maybe a year. When not finishing the job in one fell swoop, vertically strung panels look better, IMO. If I was going straight to finish, I probably would hang them horizontally. If that is also a factor in your project, you might consider it.

 

[graffix000]

Go vertical with the 10' lightweight sheets and it is not bad to do. Just did my garage a month or so ago.

 

[j p smith]

Curious about the answers because when they did my shop all were done with long sheets horizontal. This may have been for less waste. Also they did the bottom sheet first, then the top, cut for the middle last. (10' walls) And I think all ends were staggered.

 

[ratdoggy]

I did my basement horizontal. Next time it's vertical, you have wall seems with factory (tapered) edge. Your taping will be easier and better looking.

 

[NUTTSGT]

10' walls, I'd probably go with ten foot sheets hung vertically.

There will probably be some good drywall guys chime in about going horizontal though. I heard it's done like that so the seam is at the 4' mark. It makes the seam harder to see as it's not at eye level.

 

[nmcqueen469]

We just finished doing two walls in the shop and my dad, who used to do drywall in a previous life, wanted to go horizontal. It makes the mudding/taping easier to deal with and finish, plus it's easier to maneuver with two people.

This was all on 8' walls though, so YMMV on a 10' wall.

 

[wbrian63]

I've only seen vertical installation by professionals a few times. Most hang the rock perpendicular to the studs, both on the ceiling and on the walls. Definitely on the ceiling - the edges help to keep the sheetrock from sagging if they're perpendicular to the studs.

If you're considering vertical installation, think about these issues:

If your stud spacing isn't 48" increments dead-on, you're either gonna fall short of a stud at some point, or you're going to have to trim something off the edge of a too-wide sheet. Trimming the edge of a sheet is a PITA. With horizontal, if you fall short, you can just cut back to the previous stud. If it's too long, trimming the edge is no big deal - score the front AND the back, then use a sureform tool (rasp for working with sheetrock) to remove the gypsum that remains.

You need to be really good at taping and floating. It's very rare to get a perfectly flat seam between sheets - usually there is a small hump spread over 12" or so. Your eye will be drawn to those 12" wide vertical humps in the wall that run from floor to ceiling. You won't notice a 12" horizontal hump 48" off the floor...

Going up and down a ladder to tape and float the vertical seams is not too fun. Hung horizontally, you've got one seam easily worked from ground level, and one seam at the ceiling (for an 8' foot installation) The ceiling-to-wall joint typically only requires 2 coats of mud - one to bed the tape, and another to cover the tape - the seam at 48" will take 3 coats to completely hide (4 or 5 if you tape and float like I do...)

You can't do 10'ers horizontally if you have 16" stud spacing (that takes 12' sheets, not typically available at home centers and not something you can do solo) - you can with 24" spacing. Larger sheets = fewer seams to tape and float - this is a good thing. The new lightweight stuff is only slightly heavier for 10' than the old stuff was for 8', and you cover 25% more wall with each sheet.

I'm not a professional, but I have probably hung, taped and floated 300+ sheets of sheetrock in my time. (And I still **** at it - it looks good - usually real good when I'm done, but it takes FOR EVER...)

One tip I picked up years ago that might do you some good. Use a 4" knife when bedding the tape. When you come back for the 2nd coat of mud, use an 8" knife that's been modified.

The mod is to bend the edge of the knife so it's not completely flat (across the width) - all you need is about 1/32" of curve. This creates one face that will create a crown of mud on the wall, and the other face that creates a dish. Mark the face of the handle so you can tell which is which.

When I put the mud on the tape (the 2nd coat after bedding the tape in), I use the crown side up first. This creates a nice layer of mud over the tape. Then I come back at each edge of the mud bed with the knife reversed to feather the edge of the mud where it meets the rock. The reverse curve keeps the edge of the knife from leaving a score line down the middle of the mud bed.

I've also recently switched to using a hawk (a 12" flat aluminum plate with a handle in the middle of the back - typically a tool of plasterers and stucco men) instead of the trays. Way easier to clean and work with the mud. For final work, I also use a metal finishing trowel - I think mine is 12 or 14" long, instead of a 12" taping knife.

Buy the lightweight pre-mixed mud. It works the same as the "standard" but it weighs less which you'll appreciate over time. I thin the mud with about 4-6oz of water per box. Then I mix it well - slowly to not add air. Even if you don't add water - get a paddle mixer and mix the mud. It loosens the consistency and makes it WAY easier to apply.

There are oodles of videos on YouTube - they give good examples of all aspects of sheetrock work.

Good luck.

 

[SlappyWhite]

If you do vertical the entire length of every seam will be (well should be) supported from behind (assuming the screws are not very far apart). if you do horizontal the seam will only be supported every 16 inches. May or may not be an issue...

 

[5mall5nail5]

Awesome tips in this thread! Thanks guys - still not sure what to do vertical or horizontal. It's not an even 10'er, it's like 10' with beam and then the front of the garage has an angle/grade to it, maybe a 25 degree pitch down for about 4' it'll be fun.. ugh

For what its worth I am only adding drywall. The garage had already been drywalled but removed for an addition and potentially a mouse problem.

That raises a second question - I have attic access to this garage room - is there anything I can put atop each stud cavity above the ceiling panels to keep future mice from going down the walls? I am going to try and seal everything up real nice and I might even throw some poison boxes up there, but I don't want to have an issue in the future and I can see during demo that a couple holes were bored through the old insulation (that I am removing/redoing). Oh, the drywall that is still up in the garage is done vertical. Perhaps I should continue that. The seems did end on the center of a stud so thats nice... though I wonder if it continues to line up as they moved along.

Thanks all!

 

[BFBOB]

The pros run it horizontally. I don't. Pros say horizontal seams are less noticeable. I say horizontal seams are harder to sand. Pros say unsupported seams between studs are strong enough. I say why compromise on strength, especially in a garage.
On your 10x16 wall with 4x8 sheets, 46' of seam vertical, 42' of seam horizontal. If you use 4x10 sheets, 30' of seam vertical, 42' of seam horizontal. I've heard of 5' drywall- probably only available at a specialty pro drywall supplier. If you use that, in either a 5x8 or 5x10, laid horizontally you'd have only 26' of seam.

Accuracy of framing has been mentioned. True, but in my case I'm nearly always doing a house with baseboard and crown molding. That covers a multitude of (small) sins.

Mice can chew through about anything except sheet metal. (steel, that is. They can get through aluminum). Hardware cloth used to be good too, but lately it seems to be made of smaller and smaller wire. Mice have itty bitty teeth, but lots and lots of time and patience.

 

[Higgins]

For what it's worth, it's easier to mud the horizontal seam than climb up and down a ladder!

If installing vertically, you better hope the studs are exactly on 16" centers so you have some material to back the vertical DW sheet with, along with something to screw into!

AL

 

[Spudland_Dave]

We just finished doing two walls in the shop and my dad, who used to do drywall in a previous life, wanted to go horizontal. It makes the mudding/taping easier to deal with and finish, plus it's easier to maneuver with two people.

This was all on 8' walls though, so YMMV on a 10' wall.

I did my 10' walls vertically...all lightweight/high strength 10' sheets. Easy to install solo, finishing only tapered seams is easy peasy.

Checked with my uncle who did drywall for longer then I've been alive and he said it doesn't really matter how they are hung. BUT he prefers horizontal cause its easier to finish. hung vertical = lots of up & down on a ladder when taping your seams, vs horizontal hung he slaps on his stilts, tapes the top sheets all around, gets off stilts and does all the bottom...or 2 guys one does the tops on stilts the other does the lower.

Other then that do as you please....biggest reason I did mine this way was installation ease and no **** joints.

 

[Hop2it]

Jon,
I am finishing up a 24x32 pole barn that is in the lowest part of the yard.I hung the drywall horizontally and had abou a 16" piece at the bottom that I used mold and moisture resistant drywall and polystyrene insulation in that area in case we get the 1000yr flood
Good luck with your project Doug Ps I will soon be posting my barn build.

 

[IHI]

Either way wont matter, just depends on how much effort your willing to put forth if/when you tape/mud the joints.

My basement only has 8' ceilings so I hung them vertically since I could easily mud the entire length of the seam standing on the ground, plus they weren't really a true 8' due to ceiling tiles in case access was needed in the future for anything.

When we built additions, garages, and such for customers, weather we hung it or my drywall subs hung it, it was always horizontal just because finishing it that way is much easier, on a typical wall height the joint is right at waist level so everything is done on the ground. Pro drywall guys use bazooka's, mud boxes, etc...on poles so they can do all they're taping/mudding on the floor anyhow, but it's unlikely a DIY'er is going to drop $5K on specialized tools just so they don't have to use a ladder LOL.

What's been mentioned above is a good point and varies per person, drywall specialty shops sell 54" x ??' rock, we always speced that when building for a 9' ceiling since it reduced seams on the wall obviously. You could spec out 54" rock and then hang them vertically against the ceiling then **** the next piece under that, and use some sort of trim board along the bottom to finish it, that way you still only have the main seam running at chest height.

FWIW, hanging horizontally allows you to use a drywall lift to lift/support the top row and hold it tight to ceiling, so other than the muscle required to flip the sheet onto the lift, nothing more is required since the lift is doing all the work at lifting/holding in place. I've never seen a hanging crew ever use a lift, but in the DIY world they are a godsent LOL.

FWIW, when it comes to sanding, since DIYer's are notorious for adding 5 gallons of mud and sanding off 4, call your rental center and see if they carry/rent out the Porter Cable drywall sander. It's a light weight orbital sander with a HEPA vac, I contemplated buying one when they first hit the market but didn't, then yrs later rented one when we rocked my 16x20 shed...kick myself in the **** for not buying one yrs ago when I had my business- NO DUST anywhere, and did the ceiling/walls in under an hour at a level 5 finish (smooth- since I didn't want any texture to hold dust)...it made the job easy since it blended out so nice.

 

[PugetDude]

Pros hang sheetrock horizontally- as others have mentioned it's much easier to tape the seams, just work your way around the room instead of ******* a full mud pan up and down a ladder that you have to move every 4'. Also, hanging the long axis horizontal tends to minimize inconsistencies in the vertical framing, i.e. bowed/twisted/out of line studs, which vertical seams would accentuate- it's much easier to "fix" framing issues with a 4' seam than an 8'+ seam.

I'm not a pro, but I've hung and taped a lot of drywall.. Horizontal is the way to go, IMO

My 2Cents worth, for free.

 

[readhead]

Pros hang horizontal for a reason. Much faster to hang. If you have a proud stud it won't show. On a ten foot wall put a two foot rip in the middle and it will be a lot easier to tape. The end result will be the same but the pros can't be all wrong.

 

[benjamintmiller]

I just hung and finished 45 4x12 sheets, and agree with everyone else -- horizontal is the only way to hang drywall.

**** joints aren't as hard to finish as everyone makes them out to be. The trick is to create a flat spot in the center, then feather them way out. I feathered mine out about 30" with a smooth finish, and you can't tell there's a joint.

I'm not sure if it's been mentioned, but make sure you use paper tape if you use all purpose compound. Mesh tape isn't strong enough and will crack unless you use setting type compound ("hot mud").

 

[Kevin54]

When you hang the sheets horizontally, you have **** seams that are your vertical seams. Those seams need to be mudded and fanned out in a much larger area to hid the fact that the mud is completely on top.

When you hang your drywall vertically, you have a factory edge at each seam that gets filled in and only spread out a small amount to the sides. Going vertical leaves a much flatter looking wall.

As far as less seams, actually going horizontal, you have more footage of seam to do. I posted up a pic quite a while back showing the footage of horizontal vs. vertical.

A lot of how it is put up depends on your drywall contractor. It actually can be hung both ways, and the work is up to the guy that muds it. Myself, personally, I prefer to hang it vertically and use the factory beveled edges to keep a flat wall. But my drywall hanging days are over anyways and I have an excellent drywall guy. As long as the price is good, he can hang it either way.

 

[rancherbill]

Pros hang it horizontally. It is easier to tape for two reasons. First, a horizontal joint is easier to finish/hide than a vertical joint and it is easier to work comfortably on a horizontal joint. Hang your drywall from the top with a 4, then 4, and a 2 on the bottom. The second reason is that studs warp during construction and afterward. A vertical wall will look as crooked as a dogs hind leg if you look along it.

Finally, buy long drywall, eg 16x4, it eliminates joint and you get a very good job. You have to buy at a professional drywall place. They will deliver it to your room - well worth the price. Nail and screw the drywall only in the bevels, for the middle of the sheet use drywall adhesive. You will never get nail pops and you never have to fill them.

Finally, ALL drywall mud has to be thinned!!! It should be the consistency of pancake dough.

 

[jasong70]

The bonus to hanging horisontally is the seam at the ceiling is noticably straighter.

On 10' walls, you hand 2 sheets and the 3rd is cut tight to the ceiling. The longer the sheet, the fewer seams. If you hang it vertically, you'll notice allot of peaks and valleys, even with the indentations at the factory edge.

I had a long discussion about it with a pro when he was doing my house.

I can tell you he knew what he was doing because you can't see any seams at all.

 

[1/2 Cup]

All horizontal in this neck of the woods. I have never seen sheets run vertically out here at all!

 

[atfulldraw]

vertical is for those who don't know better.....

I hang by myself and use a lift - much easier to carry and place horizontal sheets on a lift as well.

 

[hotrodhog]

I ran 4x 8 sheets horizontal on 16 foot side walls (I was working by myself so 8 foot was all I could handle on a ladder!) I also put treated 2x4s long the floor and started the sheetrock on top of the 2x4s so it wasn't right down to the floor (in case the floor gets wet for a number of reasons....

 

[benjamintmiller]

You say you have lots of outlets to cut out, and want to know what tools you need.

Here's what you need, at a minimum:

• 4" knife for tape bedding
• 6" knife for first coat of tapered seams
• 10" knife for first and second **** joint coat, second and third tapered joint coat, and second and third corner coat
• 12" knife for final coat of **** joints
• Mixing paddle, because joint compound needs water added
• Paper tape
• Corner bead for outside and inside corners -- I like no-coat or strait-flex
• Empty 5 gallon bucket for water
• Utility knife
• Drywall T-Square
• Surform plane for smoothing cut edges
• Chalk Line
• Drywall screwgun and screws
• All purpose joint compound -- the stuff with a green lid has more glue for bedding tape, and the stuff with a blue lid has less glue for easier sanding of top coats
• Pole sander with sanding mesh
• Sanding sponges for feathering edges and corners

I additionally recommend these tools, if you have the money:

• Drywall lift for ceilings. These can be rented
• Senco collated screw gun and screws
• Rotozip for cutting out outlets
• Rock Ripper square for fast rip cuts

Be prepared to spend hours and hours on this. If this is the only room you plan to finish, I HIGHLY recommend getting a quote from a professional. I know for sure that the labor I put into my 45 sheet project was way more than the $900 I had quoted from several people for finishing. Expect $.30-$.45 / sq ft for finishing, depending on finish.

 

[gm54210]

Hang your drywall from the top with a 4, then 4, and a 2 on the bottom.

One other note on going horizontal. Unless you hang with a cut edge at the floor as recommended by Rancherbill, the factory taper will need to be shimmed out for any base trim applied.

 

[Cobra6]

I've only seen vertical installation by professionals a few times. Most hang the rock perpendicular to the studs, both on the ceiling and on the walls. Definitely on the ceiling - the edges help to keep the sheetrock from sagging if they're perpendicular to the studs.

+1 - I have never seen vertical unless there were some weird angle spaces or chopped up rooms.

 

[rslaback]

Every time I've ever done it (professionally) it was done with the sheets horizontal.

If it was supposed to be installed vertically why would they make 12' and 16' sheets?

 

[Kevin C]

I went vertical... No **** seams using 9' sheets (1' stem wall). It worked out to about 20% less taping than horizontal and having to put up three rows.

Seemed like a no brainer even though its not how a pro would do it. First time with sheet rock and it came out great.


Part of this might be that a pro is better at taping seams... For me, it was all about minimizing seam length, so I was OK with a little extra work hanging the material.

 

[planecrazy]

As an ex drywall pro, horizontal. Much easier. Start hanging the walls from the ceiling and work down the wall. Not sure where your outlets will be, 16" or 48" off the floor but try to get them out of a seam, if possible. You can get 54" wide drywall to help adjust the location of your seams. Get a toe kick to lift the bottom drywall sheet up against the previous sheet. Make sure and keep a gap at the floor, 1/2" or so.

Keep the joints as tight as possible but don't spend too mush time on that. Mud covers a multitude of sins.

A roto-zip is the best way to cut out around electrical boxes, after the drywall is loosely fastened to the wall.

Use glue on the studs and less screws. Don't use glue on the studs where the **** ends fall. Why, because the glue oozes out and drys hard. It takes more time to clean that mess off to get a smooth finish. If you have a vapor barrier or kraft paper over the studs, don't bother with the glue.

 

[trainer]

Finally, ALL drywall mud has to be thinned!!! It should be the consistency of pancake dough.

I disagree with this.
if you thin the compound out, it shrinks more when it dries and is harder to scoop up and hold on your knife, especially on ceilings.

Fresh, good quality compound straight from the bucket works for me. Two coats, the first to cover the tape and the second to finish filling the taper and feather out the edges.

I got a bucket of store brand compound recently that was quite thin and the second coat shrank so much that I had to add a third coat to finish it properly.

 

[IHI]

I disagree with this.
if you thin the compound out, it shrinks more when it dries and is harder to scoop up and hold on your knife, especially on ceilings.

Fresh, good quality compound straight from the bucket works for me. Two coats, the first to cover the tape and the second to finish filling the taper and feather out the edges.

I got a bucket of store brand compound recently that was quite thin and the second coat shrank so much that I had to add a third coat to finish it properly.

Point being about thinning it down is because it helps PREVENT diy'ers from installing it too thick which WILL cause cracking. Mud is like painting a car, thin coats will get you further, faster, with overall less work than trying to blob it all on with thick coats.

There was a drywall thread the other day with all the things listed to do the job efficiently, and straight bucket mud/box mud is THE biggest DIY mistake made everyday. Even the pro's that use bucket/box mud to load their tools thin it down. When I kept drywall in house I preferred to bed the tape using hot mud first two coats and skim it all the edges with bucket/box mud thinned down to mayoonase consistancey, it's much easier to manipulate the knife and get a "close to paint ready surface" with a thinned down final coat and minimized sanding to sanding the room one time, and that's just to knock down/feather in the edges. If you find yourself sanding a room more than once, you need to refine your technique.

Believe me, it's easy to say at this point in time working with my subs and being taught tricks over the yrs, so it's hard to describe it to somebody..it's one of those things you need to see along side an experienced mudder and then the light bulb comes on and you slap your head in a DUH moment. Point being, ya never use premix straight, it's simply too thick and will always end up with spots that crack from shrinkage due to that fact.

 

[rancherbill]

I disagree with this.
if you thin the compound out, it shrinks more when it dries and is harder to scoop up and hold on your knife, especially on ceilings.

You watch the youtube vids and watch the pros do it and they all thin the compound. Using it unthinned will tend to put more compound on the wall. If you watch a pro they do very little - I MEAN VERY LITTLE - sanding after first and second coat. If you do not put on excess you do not have to sand it off.

 

[5mall5nail5]

As an ex drywall pro, horizontal. Much easier. Start hanging the walls from the ceiling and work down the wall. Not sure where your outlets will be, 16" or 48" off the floor but try to get them out of a seam, if possible. You can get 54" wide drywall to help adjust the location of your seams. Get a toe kick to lift the bottom drywall sheet up against the previous sheet. Make sure and keep a gap at the floor, 1/2" or so.

Keep the joints as tight as possible but don't spend too mush time on that. Mud covers a multitude of sins.

A roto-zip is the best way to cut out around electrical boxes, after the drywall is loosely fastened to the wall.

Use glue on the studs and less screws. Don't use glue on the studs where the **** ends fall. Why, because the glue oozes out and drys hard. It takes more time to clean that mess off to get a smooth finish. If you have a vapor barrier or kraft paper over the studs, don't bother with the glue.

Awesome info - thanks! When you say "toe kick" do you mean justa piece of wood? Also, for electrical boxes mine are 49" at the bottom of the box to the floor because I wanted room to lean 48" wood or sheet metal without blocking an outlet. so, I guess I will have them at a seam. Oh well. As for cutting around outlets, do I hang the drywall over the outlets and then... how do I find the outlet boxes reliably?

 

[5mall5nail5]

You say you have lots of outlets to cut out, and want to know what tools you need.

Here's what you need, at a minimum:

• 4" knife for tape bedding
• 6" knife for first coat of tapered seams
• 10" knife for first and second **** joint coat, second and third tapered joint coat, and second and third corner coat
• 12" knife for final coat of **** joints
• Mixing paddle, because joint compound needs water added
• Paper tape
• Corner bead for outside and inside corners -- I like no-coat or strait-flex
• Empty 5 gallon bucket for water
• Utility knife
• Drywall T-Square
• Surform plane for smoothing cut edges
• Chalk Line
• Drywall screwgun and screws
• All purpose joint compound -- the stuff with a green lid has more glue for bedding tape, and the stuff with a blue lid has less glue for easier sanding of top coats
• Pole sander with sanding mesh
• Sanding sponges for feathering edges and corners

I additionally recommend these tools, if you have the money:

• Drywall lift for ceilings. These can be rented
• Senco collated screw gun and screws
• Rotozip for cutting out outlets
• Rock Ripper square for fast rip cuts

Be prepared to spend hours and hours on this. If this is the only room you plan to finish, I HIGHLY recommend getting a quote from a professional. I know for sure that the labor I put into my 45 sheet project was way more than the $900 I had quoted from several people for finishing. Expect $.30-$.45 / sq ft for finishing, depending on finish.

Thanks for the list of stuff! I have everything except a dedicated drywall screw gun. I have a normal impact driver and drill which should work. I am not drywalling the whole room - its only maybe 16' long and to the ceiling. No ceilings need to be done.


Does anyone know how much it costs to rent a drywall hoist from Home Depot? I won't be able to lift the drywall horizontally to the ceiling myself.

 

[Davefr]

Go 4X12 and hang horizontal.

 

[malibu101]

On a commercial job is was on a few years ago I saw drywall sheets that were 4.5' x 8' (and 10' and 12' long) Until then I never saw drywall other than 4'. I have not seen 4.5' sheets since either.

Reason was the walls were 9' high so (2) 4.5' sheets hung horizontally made 9'. Just one horizontal tapered seam right in the middle. Of course walls longer than 12' had **** joints vertically.

Moral of the story- I guess there must be alot of people hanging it horizontally for a drywall manufacturer to bother to make a "special" size.

Link to 4.5' sheets- http://www.lowes.com/pd_212102-272-GB06091200_0__?productId=3446738

 

[wbrian63]

Drywall lifts won't help you on the walls - at least the one's that HD rents won't.

Here's what I do when working alone. Assuming you've got 16" stud spacing, screw a drywall screw into the 2nd and 5th studs of those to be covered by the sheet (a 4x8 sheet covers 7 studs (the first and last are only covered by half, assuming an open span installation - no corners).

The screw should stick out about 3/4" and be placed 48-1/2 or so down from the ceiling.

Have your drill and screws at a place where you can reach them easily after this next step.

Lift the sheet from the edge and walk it over to the wall. Let the top edge tip onto the studs and lift it up and set it on top of the screws you put in the wall.

Get the sheet positioned left and right, then start a single screw in the edge of the sheet about 1" in on the stud that's in the center of the sheet.

Lift the sheet up to the ceiling and set the screw with your gun. You may need to lean against the sheet a bit to keep it from tipping out as you lift.

That will hold the sheet long enough to get the other screws installed.

Don't put any screws in the ends of the sheet until you get the next sheet butted against it. The ends will "blow out" making installation of the next sheet a problem. Once the edges are touching, the drywall is far more stable.

Also - do not be tempted to put a screw into the stud immediately adjacent to an outlet box, or between two boxes straddling a stud. The opening in the wall makes for a mess when trying put mud. Just move up or down from the box about 6".

If you're going to use a rotozip to cut out the boxes, make sure you've not installed the drywall where there's too much tension from behind. As you're cutting out the blank, the drywall will break and tear when the tension is too great for the drywall to bear.

I'd use metal boxes for a first timer with a rotozip. When I did my first install with a rotozip and plastic boxes, I moved too slowly with the 'zip and melted through the edge of the boxes in serveral places, making for a real mess.

If you're not going to use a rotozip, you can get some cheap lipstick at the drugstore. Mark the corners of the outlet box and set the sheet in place - pressing it against the box. That will give you an outline of the corners for the box cutout. Of course, you have to make sure the sheet is perfectly aligned for this tip to work.

Good luck.

 

[5mall5nail5]

Also - because this is a garage is there any reason to use moisture resistant drywall or fire dry wall? I am doing 5/8" because that's what is currently up in the sections that have not been removed.