Basement: Rough Carpentry

Rough Carpentry & Framing

With the plans complete and permit in hand, it was time to start rough framing! Now, here is an area of construction that sparks intense debate: the best way to frame the perimeter and partition walls in a basement. The walls do not have to support any structural loads but done incorrectly your finish surfaces will not be smooth and continuous.

1. Mark on the bottoms of the floor joists (i.e. the ceiling) with a chalk line where the inside edge of the top plate would run.
2. Nail a top plate to the floor joists along this line. For areas where the top plate runs parallel to the floor joists, nail 2x4 blocking between the floor joists every 3 feet or so, to give something for the top plate to nail to.
3. Fill in any space between the top plate and the first floor sill with ripped 2x material to make a fire stop.
4. Drop a plumb bob from the top plate to the concrete floor and create a chalk line along the floor for the bottom plate.
5. Lay a pressure treated 2x4 along this line, then place another 2x4 (a second top plate) on the pressure treated 2x4, then measure the distance between them and the top plate on the floor joists above - this is the lengths to cut your 2x4 wall studs.
6. Frame up the wall and tip it into place. The two top plates are structurally unnecessary, but doing it this way makes tipping the wall up and aligning it plumb very easy. Plus, end nailing all of the wall studs is much easier and stronger than toe nailing everything.
7. Fasten the pressure treated bottom plate to the floor with Tapcons every other stud bay. You can use some Liquid Nails for additional strength if you want (I did for the knee wall for the bar).

At this point, you may have noticed that I also applied insulation at this time between the framing and the foundation. The material I used is 1" thick extruded polystyrene (XPS) and is part of the recommended practices from the Building Science Corporation. See the section on insulation for more details of why I built the walls this way. Applying it is easy - just a few dabs of Liquid Nails every 2 feet or so will tack it in place (the wall framing holds it in place permanently). Note how I taped each seam with the recommended tape - this is important to minimize air movement and potential condensation.

The stairs required some modification - I replaced most of the treads and risers with ones that were about 6" longer. This was to accommodate additional width for the railing and baluster system (see finish carpentry later), and to permit framing the side wall neatly. Fortunately, since the existing stairs already had good rise/run geometery, I did not have to alter the stringers.

Framing soffits around the beam and drain pipe was easy - just make ladders from 2x2's then nail the ladders to the floor joists. The ladder height should come out about 1/4" below the lowest object in the soffit (in my case it was the I-beam), so that the drywall will just clear the object. For soffits narrower than 24" or so, you really don't need to connect the ladders to each other - the drywall will work just fine by itself.

One last comment on rough framing - USE A POWER NAILER! I borrowed a friends Paslode cordless and man, it made all the difference in the world! Framing was so much faster and better. I think I used about 1,500 nails on the rough framing and it was so much faster, especially when nailing overhead.