Framing Over a Complex Foundation, Part II

I begin by cutting in the plates for each individual wall section and determining the stud height. To get a stud height we use a laser to shoot a line across the rear of the house and check measurements every 8 feet.

It's important to pull stud locations from the same corners as those we will use to pull joist and rafter locations. That allows us to easily stack studs, joists, and rafters, providing for direct load bearing from roof to foundation. This also creates the clearest possible stud bays, which makes life a bit easier for the mechanical trades that will follow behind us.

Using our laser and the telehandler, we level the beam.

Then we make sure it's parallel to the front wall. Once it's level and braced to the exterior wall with a 2x6, we measure from the concrete to the bottom of the beam. With this number we can make a triple 2x6 column to carry one end of the beam.

As we're installing the steel, the other crew members stand up the shorter of the drop walls and nail them off to the sills.

Working together, the entire crew picks up the long wall across the back of the house and places it on the top of the foundation wall. We nail the long wall to the plates as well as to the smaller walls, which will temporarily hold it in place.

To give us one set height for the entire first-floor deck, we align the first (lower) top plate on the drop wall with the PT sill on the full-height foundation walls. Then we run a second KD sill plate around the perimeter of the foundation that laps onto the drop walls as the second top plate.

With such a long drop wall, it's important to make sure it is parallel with the foundation wall, which we confirm by measuring the distance between the rear and front walls at several places. We use 2x6s to brace the drop wall back to the steel, which we had tied to the front foundation wall earlier, providing us with a solid connection point.

With the layout complete, we're ready for joists. The first step is to install the rim board along one side of the building—in this case, along all the front walls of the house. We then load the telehandler with all of the I-joists and begin spreading them out, starting from the gable end and working outward. This has the advantage of giving us a safer surface to walk along as we go.

As we spread out the joists on the plates, we put them tight to the rim board on the front sections and make sure that both ends are on their layouts. Because we have no anchor bolts in the foundation, the joists can sit flat and straight, which allows us to snap a clean line along the back of the house and cut all of the joists while they're laying flat.

Once all of the joists are cut, we frame in the stair openings with LVL.

Three crew members begin rolling up the I-joists and nailing them off at our three attachment points.

For the rim running perpendicular to the joists, we typically install an engineered rim board material that's compatible with the I-joists, and on the load-bearing sides running parallel to the joists we install an equivalent size LVL.

On the walkout side of this house, we didn't have enough head clearance for a regular header, so we installed a flush LVL header above the door in the basement wall.

While the rim was being installed, we also installed all of the necessary blocking. Blocking at 16-inch centers is required to support the exterior walls on the LVL sections of the rim. Blocking and web stiffeners are also required for any intermediate load-bearing walls, which we had above our midspan girder.

To install the anchors, one crew member drills the 5/8-inch–diameter holes through the sills and into the concrete.

A second cleans out the hole using an air hose.

A third crew member then drives the bolts with an electric impact wrench.

In the morning, we returned to install the subfloor across the deck. To save time, we deck right across the stair openings.

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