How House Construction Works

Floor

The framing crew is the next group of people on the site. They start by building the floor (unless the house uses a slab foundation, in which case the slab is the floor). The floor framing looks like this:

The floor starts with a sill-plate made of pressure-treated lumber in direct contact with the bricks of the crawl space wall. One interesting thing to note is that this house literally "sits" on the foundation -- it is not held on or bolted on in any way. Then the floor is constructed on the sill with 2x10 lumber:

How House Construction Works
How House Construction Works

You may have noticed the brick posts when you saw the picture of the foundation. They hold a beam that runs down the center of the house. The beam is also built from 2x10 lumber (three pieces thick):

How House Construction Works

All of the "joists" (as the 2x10s in the floor are called) meet on this center beam:

How House Construction Works
How House Construction Works

(In many houses the meeting of the joists is somewhat better organized!)

This funny little cantilevered section of the frame will eventually hold the fireplace:

How House Construction Works

Once the floor framing is complete, it is covered with 1/2-inch or 5/8-inch plywood or OSB (oriented strand board).

How House Construction Works

And the floor is finished.