Beam Project: Measurements

The first step is to get all of the precise measurements and check how far off of level we are. I bought a laser distance measure and a self-leveling cross line laser level. These were each about $100 each and in addition to being incredibly helpful for this project will be useful for many of the projects going forward.

Checking beam level

I started by checking the beam for level. I drew a mark under each floor joist along the laser line and then measured from the joist down. I then marked which joists were lower or higher than average. The variance was about a half inch in either direction. Then I turned the level the other direction to check the floor joists. I found that the floor joists sagged by about an inch from the outside wall to the beam. Determining level without the laser would have been painstaking and not as accurate. I have a six foot level, but using it to find the level of the whole basement would have sucked. Since you can’t trust the beam, the joists, or the floor to be level, all you can do is find variance. This will be especially important when I dig the footings so I know how deep to make them.

Checking joist level

I also measured the length of the beam. It is pocketed into the brick wall at either end, so I slid a piece of metal in to determine how deep the pocket is and added that to the total, which is roughly 44′. There will be two columns, so we’ll split the beam into three sections. The challenge in positioning the columns is that the floor above will also have open spans, so those columns need to be directly above the columns in the basement. The spans should be as short as possible, because their load bearing capacity drops exponentially with length. I referred to the floor plans, but a couple of the dimensions were off, so I had to adjust to get the exact locations of the columns. I determined the longest span will be 16′. Conveniently you can multiply 16′ x 24 lbs and get the weight: 384 lbs. This job will require some help.

Marking the footings

Finally I marked out the location of the footings on the floor. Unfortunately, there are studs and a 4×4 in the way, so I need to build the temporary wall so I can remove it. That means it’s time to get some jack posts and crank up the house.