19

I will be installing drywall in a 10x10 room this weekend, walls only. I'm planning to use the longer sheets so there is only a single horizontal seam on each wall and install the top sheet first, flush against the existing ceiling.

My question is, what is the best/easiest (not usually the same thing) way to cut holes for the receptacles as I'm hanging the bottom panels of drywall? I'm considering a few options, but what is the best for someone new to this for a good result? One option is to just hang the drywall and use old-work boxes for the receptacles. I don't like to use old work for new work as it doesn't seem as secure. Personal preference. In the past, I've nailed up the boxes and then tried to cut the holes by measuring from the sides several times and then cutting out the holes before putting up the board over the boxes. That never seems to come out in the exact right spot that I don't have a gap around the box. Lastly, I've installed the boxes and then used a saw or rotary tool to cut it out with the drywall loosely fastened into place. This always seems to damage the wiring and still leaves a gap around the box where I cut.

So, which of these methods are mostly likely to work with practice or is there a super slick method that I haven't even thought to try?

|improve this question|||||
  • 1
    if you measure well, up and down from top piece and side to side from an edge, you will be fine. Cut 1/8 inch larger and hang it. mud does the rest. Simple, Amen. Don't over think it, just do it! – shirlock homes Jan 28 '14 at 22:43
13

My experience says to use the rotary tool, but I have always used metal boxes with plaster rings. I have no experience cutting drywall over plastic boxes. I do have three pointers for cutting with a rotary tool:

  • Put as little pressure on the box from the drywall as possible. The more pressure against the drywall, the more likely that you'll get tearout near the edge of the box.
  • Leave any NM cable sheathed and set the depth of the cut to the minimum possible to reach the box plus a half an inch (keeping in mind that the drywall will be at an angle to the box).
  • Always take a few seconds to visualize your cut. Have a good idea of where your corners are so you can anticipate direction changes. Do a sanity check and make right sure you know which way counterclockwise is. Start out going clockwise, and you'll spend a lot of time repairing drywall.

If you still don't want to use the rotary tool, there is another option. There are tools that attach to plastic electric boxes. You put them on and then position the drywall where it will be installed. Press the drywall against the tool, and it will place small perforations at the outside corners of the box. Connect the dots and cut. The image below is of one of mine, but I haven't had the chance to use it yet.

Thing that attaches to plastic boxes

|improve this answer|||||
  • While I haven't used those pin-plates, I think they are likely the best option. I used a rotary tool on a remodel and holy #&@^#$ does that make an ungodly mess. Never again. :) – DA01 Jan 22 '14 at 18:01
  • 2
    There's a trick for the mess. Hold the router in your right hand, and a vacuum hose in your left. If you put the hose end in the right place, it sucks up ALL the dust. I do have some "wear" marks on the ends of my hose, though. – Edwin Jan 22 '14 at 19:38
  • 3
    I had never seen those plastic marking tools before so I did some searching. I found 2 different styles that work a little differently. The ones from Handymark are like pictured above where it pokes holes and you remove the panel to make the cuts. Then, I found these magnetic hole guides from Blindmark that don't require you do move the panel once you hang it. The outer guide 'finds' the guide that you put inside the box and you can make the cut right away. Both clever and I'm going to check for these at the improvement store. – dslake Jan 22 '14 at 20:15
7

I prefer to hang the drywall loosely and use a rotary tool. But make sure you use a bit designed for this purpose -- the proper bit will have cutting flutes that don't extend all the way along the length of the bit, leaving a smooth round tip. This tip will follow the contours of the box without cutting into it, even if it's a plastic box.

Note that if you apply too much pressure on the box or linger too long in one place the smooth tip will still heat up and melt plastic, so use light pressure when following the outline and keep moving!

|improve this answer|||||
  • This is a good way to do it, bust still need a reference measurement to start from. – shirlock homes Jan 28 '14 at 22:38
6

Gaps around boxes are normal when hanging drywall. The standard tool for a beginner is a keyhole saw and careful measuring. Realize when measuring that drywall will likely have up to a 1/4" gap with whatever it's adjacent to, so pad your measurements appropriately. That padding also needs to account for the box itself. So with the wonders of ascii art, you get:

wall                 box 
 |        X"        |--|
 | <--------------> |  |
 |                  |--|

If the box is B" wide, and the measurement from the wall to the near side of the box is X", then the left side of the cut will be a roughly X" - 3/8" (gap for wall and box are added to each other), and the cut for the right side of the box will be at X" + B" (the gaps cancel each other out). Double check all measurements to be sure you haven't reversed anything (right/left, top/bottom).

Next, factor in where you can hide gaps. With the ceiling, the sides will be hidden by the drywall on the wall, so you can allow for gaps as large as 1/4-1/2" without being noticed. And with walls, depending on which way you are overlapping, you may be able to have the same allowance. Around doors, windows, and the floor, things will be covered by trim that will easily hide a 1" gap, so there's no need to be perfect around these.

The reason small gaps around the boxes themselves are no big deal is that you seal these up with drywall mud while you're doing the seams. If you walk through a home being built after the mudders have gone through, most of the outlet boxes will have a large blob of mud that has settled to the bottom and need to be cut out. Then, any imperfection in the mud is sanded and finally covered by a switch plate.

|improve this answer|||||
6

Chalk. Rub chalk over the boxes and tap the drywall against it. The chalk outline will appear on the back of the drywall and you can cut a pretty tight hole.

|improve this answer|||||
1

The key is to hang the dry wall perfectly level. Then any measurements you make for cutting holes or trimming edges will be right. If you are hanging it horizontally just snap a level chalk line 4'1/4" above the floor on the wall and hang it to that line. The gap at the floor will be covered with base molding.

As far as cutting holes for receptacles buy a drywall knife for five dollars. It is shaped like a knife with teeth and pointy end.just push the knife through the drywall and saw out the hole.

Remember to hang it LEVEL, measure twice and cut once. Hope this helps

|improve this answer|||||
1

I haven't hung new drywall in a long time; but when I used to, I used to put something glooey on the receptacles, like gasket sealant or prussian blue, on the outlets and press the wallboard up against it; then cut it before hanging the wallboard.

These days, when I put new outlets into my house, I just use the clamping type outlet boxes in existing wallboard. I use a stud finder, if I want to secure to a stud, then cut the hole and insert and clamp the box. If I want extra support, I side screw it into the stud. I have done the same with ceiling light boxes, for exact positioning, by installing pieces of strapping in the ceiling through the box hole, and screwing them into the ceiling joists; then screwing the clampoing box into them.

|improve this answer|||||

Not the answer you're looking for? Browse other questions tagged or ask your own question.