Steel Retaining Walls
We have been busy over the last several weeks welding some steel retaining walls in central/West Austin, for the Bodle residence. The design was already completed by another company and the clients merely wanted us to install per specifications. Since this was a steel project, we were excited to fabricate the walls even though it wasn’t our design. There were some interesting moves. However, there were some issues that came up along the way that had not been solved for during the design process. This has reinforced why we love working from soup to nuts on any project, because not only are we connected to the build steps while behind the computer, but also that we are still designers while installing and fabricating.
It was a three-week stint, and OES came in on time and on budget again for this project. The site was steeply sloped and had a degraded concrete walkway up the center. The first few days were spent removing a tremendous amount of soil that was cut for the retaining walls. During the first week the walkway was removed, steel posts were set in concrete, and the welding began. We welded up until the last day, so it was about two weeks straight of welding. We subcontracted a concrete installer for the pavers and oversaw that the quality of installation was up to our strict standards. The final tasks involved final grading, sod cutting on one side, replacing the sod on the other side, and cleanup. Also, the client really liked the look and color of the steel before it started weathering. We cleaned off the surface with acetone and sealed it with polyurethane. We sod cut and left exposed soil per a request from the client so they could install plants in a clean slate. The grass never liked to grow there, so it’s best not to fight it.
Overall the project went smoothly and was really fun to install. OES is really adaptable to any site and we consider ourselves problem-solvers. The site’s drainage all accumulated in the bottom right corner of the site. The water pooled and had not been solved for in the design. We drilled weep holes in the curb and added some river stone to help the water permeate. This worked out nicely.
Speaking of custom solutions, I think it’s important to bring up a request we’ve gotten a lot of lately. Many potential clients want to have us weld up and drop off a steel patio in a square or “L” shape and let them do the installation. We are extremely hesitant to do this. Why? No ground plane is perfectly flat (unless it’s been pre-graded, I should say). Many a Sketchup drawing has a plane of steel going along at one continuous height, yet when we are on site we have to decide to get a taller or shorter piece to adjust for change in grade. It’s inevitable. If we came over with a pre-fabricated shape, we would have to weld on “band-aids” or make cuts to allow the patio to sit level. Here’s the take-home message: there is a decent amount of labor to install the patio, and every project is custom in some way. Since each project is custom, there will be reactions on site to the ground plane, type of soil, drainage, you name it. If we were to design a landscape or piece of furniture and hand it off to a separate company (or even the client who has not had prior experience with solving for this kind of thing), we would be relying on them to make the decisions for change orders or adjustments. Since we are a design/build company, we have the eye to create a good-looking product with the knowledge of how to make it come to life.
Sometimes when solving for new design challenges, out of necessity we develop new techniques that inform our methods of installation. For example, we don’t normally use posts when installing steel walls shorter than 8″, but given the height and that it was meant to retain, we upgraded to posts over rebar for strength. While it added a small amount of installation time, the quality and straightness of the line was absolutely noticeable. EDIT: Since this project, posts set in concrete is our preferred method of installation for any steel retaining wall over 3"; we use angle with rebar for edging for 3" and shorter.