A staggered joint is important for wall strength and for optimum finishing. In drywall "joint" refers to the short end of the board. Professionals attempt to eliminate joints whenever possible. They are harder to finish, use more materials and take more time.
This is the reason commercial drywall contractors use the longest board possible. If the majority of the rooms in a house measure between 11' and 12' a contractor will use 4' x 12' board thus eliminating joints completely.
Staggering a joint simply means ending parallel sheets on a different ceiling joist or wall stud. Masonry walls use the same principle. If all the joints ended at the same place the wall would crack. In masonry work the wall would collapse.
When you can't eliminate joints hang the first sheet on the ceiling or wall using the longest length possible. This helps to ensure you start out square. On the next parallel sheet your best option is to start from the other end of the room once again using the longest sheet possible.
A perfectly square house with perfectly square rooms is a rarity indeed. Following the contour of the walls will lead you astray and make the rest of the job all that much harder. You may need to leave a bit of a gap along the wall to keep your first board as straight as possible. Remember you have a full half inch of drywall that will take up the slack.
Use the last joist or stud the board lands on as your guide. The chances are good it is fairly straight. At least, the odds are better the joist is straight, rather than the odds of the corner being perfectly square. The end of the board needs to be as close as possible to dead center on the joist so you have room to nail, plus have an equal distance to start the next sheet.
Make sure you use the factory end where the next sheet will join. The end you have to cut should be nearest the wall. Always keep factory edges together when possible.
If any of your electrical outlet boxes are circular you will obviously need to cut out circles in your drywall. A drywall circle cutter is a relatively inexpensive tool. It is easily adjustable to the size you need. You only need two measurements; X marks the spot you sink the point in to. The cutter wheel scores the board and you then use a keyhole saw to complete the cut.
Another option is a drywall router. This approximately $100 tool won't likely be a sound investment unless you intend on doing a significant amount of drywall. Once again, two measurements are needed. Only in this case you don't precut the board.
This is the professional choice for speed and accuracy. An out-of-square corner won't throw your measurement off and it is an extremely fast way to make cut outs. Once you're good at it, it's faster, anyway. One of the most common rookie mistakes is getting wild with the router. Slow and steady is the rule until you're comfortable with it.
Mark the spot of the rough center of the box. After the board is in place (without being pressed firmly against the studs!), turn on the router, plunge the router bit in at the spot and run it until you hit the inner box edge. Back off just enough to slip the bit out of the inside and move to the outside. Use the box itself as the template for the cut.
CAUTION - before you get to this point make sure the electric wires are pushed deep into the box!
Additional tips- An old fashioned protractor can be used to draw a circle on the board. If you're only making one or two circle cuts this may be the best choice.
Remember this - if you cut the hole small you can always trim a little more to get an accurate fit. Heard the old joke; "Darn! I cut it twice and it's still too small!"? Taking care on the hanging will make life so very much easier when it comes to the finishing.
I'll save angles for the next post. We have a lot to cover.
Dear readers, please feel free to post questions at any time.