This week’s climbing barn update will focus on the concrete foundation and footer. Josh is building an expansion on the existing barn that will become a bouldering, yoga, and general training space, and the first steps of the expansion included digging, framing, and pouring the foundation and footer. In case you’ve missed the previous posts about the climbing barn, you can visit them here: Plans for the Barn and Climbing Barn: Ledger Boards and Framework.
To begin, Josh measured out the dimensions from the engineer’s drawings and marked the future footer on the ground with surveyors flags. Let the digging begin! He dug out the footer to a minimum of 18″ below grade as per Nelson County code so the footer is below the frost line. Once the footer trough was prepped, he and friends (thanks, Jake and Stephen!), built the internal framework out of #4 rebar and the concrete mold out of 2×4 lumber and 3/4″ plywood.
Here’s a detailed step-by-step (with lots of pictures) for building the rebar and wooden mold:
Take proper measurements for the rebar lengths and for the wooden mold dimensions.
Then mark the rebar using a wax crayon and bend the rebar using a rebar bender to create the necessary shape for the footer.
Rebar “chairs” sit on the ground and ensure that the rebar remains suspended in the concrete, offering support to the footer and protecting them from rust and corrosion that can be caused by water in the ground.
Connect pieces of the rebar using bar ties and a twister tool. The twister tool makes tying the rebar together a snap!
Below is an image of the shaped and connected rebar, suspended in place by plastic chairs.
Next step is building the wooden mold for the footer. Using the measurements for the foundation footer, cut the lumber and assemble the frame with screws.
Connect the corners of the wood frame in place to make sure that everything fits properly in the dug footer. Use straps of wood to prevent the mold from pulling apart once the heavy concrete is in it. After the rebar and wood frame are installed, fill the dirt back in, surrounding the mold on the outside (don’t fill in the interior of the mold).
Next is a pretty exciting part – concrete! Josh hired a “ready-mix” concrete company to deliver concrete, and while the concrete was poured, he guided the concrete to make sure it was evenly dispersed. He also vibrated the concrete in layers to remove air and level the footer.
I helped out by evening out the surface of the concrete with a trowel to make the texture smooth and level. It’s helpful to mark the level line on the mold or use a string level at this stage.
Almost done. After the concrete cures (this depends a lot on the temperature and the mix but it is usually hard enough to break it out in a day or so), clear away the surrounding dirt from the outsides of the frame so that the wooden mold can be removed. Once the wood is removed, the dirt can be replaced. Beautiful! After all those steps, we now have a sturdy concrete foundation and footer for the climbing barn expansion.
To prepare for the next steps of the climbing barn expansion, which will include framing out the expansion, Josh demolished the existing wall (saving all the wonderful “reclaimed” hardwood for future projects).
Stay tuned for more updates on this project in the next few months! We are so excited just thinking about climbing and bouldering in the barn.