Plumbing the outer wall using a string line, level, and turnbuckles
Last time, Ben Bogie and crew stood walls, pulled the bottoms into line, and tightened up the tops. Just before bailing out for the day, they braced the walls to be roughly plumb. Today, they’re going to align the tops of the walls perfectly with the bottoms.
First, Ben walks through with a level to get a feel for where the walls are now. He marks which way the wall needs to move on the studs.
In general, you start with the corners, getting them plumb and braced tightly. Theoretically, if the floor is level and the walls are square, then you really only need to plumb one corner and tighten the top corners.
But the map is different than the terrain.
Plumb the corners first
Ben uses turnbuckle-style concrete wall braces to move the walls. (He learned this from Mike Guertin and Rick Arnold, as he is quick to point out.) The turnbuckle is screwed to a long 2x4 and hoisted into place.
The top is screwed into the top of the wall and the bottom is screwed into the bottom plate.
Now, Ben cranks the turnbuckle until the corner is plumb.
“You can only get the wall to move so much in this direction because it's sheathed, but… you can usually get some out of it.”
With that corner plumb in one direction, the other end of the wall is also plumb in that direction, so he can pull out the tacks and flush the outer edge of the other wall, double-checking with a level.
Now they focus on plumbing the corners in the other direction, fastening the wall brace and twisting into perfection.
With the corners exactly where they need to be, Ben and Liz go about straightening the top of the wall. They add a few braces to those parts of the wall with big humps and wumps, slowly bringing the wall into alignment with the string line.
Move midsections in or out into alignment
Ben screws down into the top plate before cranking on the brace.
“I put screws through the top plate because sometimes if you’re trying to push the wall, it wants to roll the top plate up and off.”
Eventually, after methodically working down the wall, the top submits to the will of the blueprints and are ready for roof trusses.
—This is the fourth part of a seven-part series on framing, flashing, and sealing a double-wall house.
