Basement Framing
It is a good idea to build the soffits first and cover all
the beams, pipes and ducts before proceeding with
the basement framing. So, first lay out the likely
edges of the soffits with tape on the floor. This is
when you can check the location of your basement
doors The basement is often the least square and
plumb; older basements are notoriously out of
plumb and least squares and may not have
basement egress windows. You may need to shim,
scab, and/or plane board to get everything straight
and level. That way you can double-check the
symmetry before actually nailing any lumber in
place. You do this after furring down the joists
above with 2x2s to create a new ceiling height just
below the bottom of any beam or ducting that is
hanging down below the joists. After you have
made your final adjustments to the soffit layout,
plumb up from the tape marks to the ceiling, mark
the layout on the joists and secure 2x2 plates to the
bottoms of the joists creating the frame of the top of
the soffits.

If polystyrene forms were used to create and
insulate the basement wall, most of these systems
come equipped with metal strips on the vertical
surfaces, which you can use to secure drywall
simplifying your basement framing. You will not
have to "fur out" with 2x2's or 2x4's like you do on
most concrete or block foundations to provide
insulation spaces and nailing surfaces. In an an
existing home that you add a sleeping room in an
unfinished basement, most areas codes require that
you install an egress window in the sleeping room
or rooms. Or, if you create habitable space in your
basement other than a bedroom and you do not
already have an egress window, most codes would
require that you install one as part of the installation
of the habitable room. Check your with the local
authorities.

Bring the plumber in before framing so he can
install drains without undoing your work. Now as
you lay the basement framing out on the floor
remembering the basement egress windows. You
can use the vent pipe as a reference point and
notch them both out to fit around the pipe. All you
do now is line up the notches with the pipe and
slide the framing into place. Go forward by raising
the simple stud walls to frame the rest of your
basement framing taking care with the placement of
your basement doors. Use pressure-treated lumber
on the bottoms of all the walls you build to prevent
moisture thus rot, and glue down the bottom plates
with construction adhesive to avoid nailing or
screwing down into the concrete slab.