Building Our Foundation 3: Supporting and Leveling Stringer Beams
This is the third post in our "Building a Foundation" series, detailing how we supported and leveled our stringer beams.
Laying our Foundation was a HUGE undertaking, so I've broken the process into several posts. This is the third post in the series, if you haven't read the first two posts check them out here:
DISCLAIMER: We are not professionals, do not use what you read here as design advise. Always do your own research and consult professionals.
With our concrete pads poured we were ready to get started with the rest of the foundation. Our foundation plan is as follows:
Cement Pads Placed in Grid- COMPLETE
Stacking Materials (Cinder blocks, Lumber)- Stacked on each pad to reach the same vertical height
Stringer (Beam)- Spanning across the stacked materials
Floor Joists- Spanning across the stringers
The cement pad placement ensures the foundation will be in the correct position on the ground. The Stacking Materials ensure the foundation is in the correct vertical position (level).
The stringer beam will span the supports, and create a strong and level base for our floor. Lets look at the materials and tools we used, followed by the process to install level stringer beams for our foundation.
Materials & Tools
For stacking materials we used a combination of recycled materials including:
Cinder Blocks (8"x 8"x 16")
Pressure Treated Lumber (4"x 4"x L)
Scrap wood (1x5, 2x4, 1/2" plywood scraps)
Recycled telephone pole pieces (10" D x 12" H)
To construct our 26' long stringer beams (7 total) we:
Purchased 2"x 10" lumber (12'-14' lengths)
Cut the 2 x 10 lumber and placed on the ground to make two 26' long sections
Stacked the wood on top of each other to create a beam 4" x 10"x 26'
Drove a LOT of 4" nails to join the lumber together
Keep in mind you will need at least 3-4 people to lift your beam when its finished.
Laser Leveling Tool
You can get away with making your own water level but we wanted to make this as accurate and easy as possible. We used a self-leveling rotational laser level. Laser level for short.
In simple terms- because I don't know a better way to explain it: You set the laser level up, it spins and shoots a laser. Like laser tag! You use a receiver/stick (it comes with the level) to determine if everything is at the same height.
Laser levels are pretty expensive to purchase and you will only be needing it once so I would recommend finding one you can rent or borrow. We were lucky enough to be able to borrow one for the day. Equipment rental stores often have them.
Installing and Leveling Stringer Beams
Our foundation required a total of seven 26' stringer beams, which run from the front of the cabin (towards the ocean) to the back of the cabin (towards the rock). Here are the steps we took to install and level the stringer beams.
1. Setup the laser level at a location outside of the foundation.
Set it up at a location and height so that the laser will be able to "shoot" directly to each stringer beam. Follow the laser level instructions to make sure it is setup correctly and level. We actually did this wrong the first time, and had to re-level when we were already half complete.... Read your particular instructions and watch a YouTube video.
2. Find the cement pad with the highest elevation.
Our highest cement pad was located on the rear corner of the cabin. We need to bring all the other stringer supports up to that same vertical height. This will ensure we have level stringer beams and don't need to do any digging or re-pouring of cement.
We placed the laser level receiver (LLR) on the highest cement pad. Then, using the laser level, shoot that height as your datum (datum is your reference point).
You will be using the laser level to bring all the stringer supports to that height.
3. Start with the Stringer Beam Furthest from the Laser Level
To avoid confusion and potentially blocking sight-lines for the laser level, we started with the beam furthest away and worked towards the level.
4. Stack Materials on the Cement Pads
Before you start, gather small pieces of plywood and lumber in various thicknesses. We had some 4x4 blocks, 2x4 and 1x5 lumber, and 1/2" and 1/4" plywood.
Start placing your stacking materials on the cement pads with the goal of reaching the datum height (the top of your highest cement pad).
Start with your largest materials on bottom, in our case cinder-blocks. If you are using wood, use pressure-treated lumber in places that may come in contact with water/snow.
Place the materials in a criss-cross pattern on the center of the pad. Aim for a Jenga tower configuration. Stack your materials until they look level to the eye.
5. Use Laser Level to Adjust Height
Next, place your laser level receiver (LLR) on top of the stacked materials. Ours will beep to indicated proximity to the datum- height. There is also a small screen with arrows that indicate whether to move up or down.
If you are below the datum-height add materials to the stack. If you are above datum take away materials. Keep adjusting until you reach the correct height!
6. Ensure All Supports are Level for the Beam
Once your stacking materials have reached the datum height, move onto the next support location for the same beam. In our case we have 4 supports for each beam.
7. Position Stringer Beam
Once all 4 supports are at the datum height you are ready to install your first stringer beam. Make sure you have 3 or 4 people to lift the beam, and wear steel toe boots..
Lift the beam so it spans the 4 supports, and ensure it is centered over the middle of each support.
Next use a 4' level across the top of the beam to ensure it is level. Although we used a laser level to ensure the supports were at the same height, we still had to do some slight adjustments by adding pieces of 1/2" or 1/4" plywood.
8. Continue Installing Stringer Beams
Once your beam is level and in place, move along to the next set of supports and beam. We installed 7 stringer beams in total.
9. Temporarily Secure Stringer Beams
Once you have two or more stringer beams in place, temporarily secure them by screwing a piece of lumber to span the beams (shown in the picture above).
10. Beer Time
This step goes without saying, but we celebrated with a few cold ones once we had all of our beams in place!
Up until now the cabin had been just a dream, but with the beams in place we could finally see it starting to coming together!