Golden Leaves Falling

Golden leaves falling on freshly finished concrete patio

Pouring a slab isn’t as easy as pouring a slab. For best results, a concrete slab should be planned, designed, and engineered. “It can be heartbreaking when people spend all that money on the color and surface treatment of a concrete floor or patio and then get bad sags or cracks because it wasn’t reinforced properly,” says Jon Giltner, structural engineer.

Patio A – Sometime after completing the remodel of a house, Lawrence and Gomez Architects designed hardscaping and Patio A (on the left) for this property in Boulder, Colorado. Patio B is the existing square patio on the right.

Proper design always begins with soil investigation. Scott of Reardon Custom Homes, general contractor, and Gary Rosson, soils engineer, discuss the ground’s conditions and get ready to dig exploratory holes. Gary then makes recommendations for soil compaction and anchoring for the new Patio A.

A wood form is placed around the compacted soil. A worker lays a grid of steel bar and welded wire. It is ready to receive the colored concrete.

Following the concrete pour, when the material is setting but still workable, the expert hands of Boulder Flatwork cast the control joints and stamp the stone pattern with molds and a dyed release powder. This process must be done quickly and by experienced craftsmen since the material leaves little room for corrections. In the two weeks to follow, Boulder Flatwork washes and seals the slab to achieve its final appearance.

The new Patio A looks so good that Patio B (an existing gray slab nearby) looks, well, gray and old. It has withstood the decades well, so we determine it is worth saving. But to freshen its looks and prolong its longevity, we call Carl Borrego of Lone Bull. He brings us samples of applied stains, dyes, and colors on concrete squares. Carl determines that a dye with matte finish is the best choice for this application, since there will be a hot tub on this patio. He polishes the concrete with a 600 grit diamond blade, a slow, patient process. Once ground, Carl determines the mix of dye colors that will achieve an overall look compatible with Patio A.

New stamped and colored Patio A on the left; Patio B on the right, polished and dyed.

Whether working on a small project such as a patio or tackling a larger foundation challenge, careful attention to the ground conditions and the inner structure of the material yields lasting results.

Photo by Beto Santillan

“Machu Picchu’s technical planning is surely the key to the site’s longevity and functionality,” writes Ken Wright. It has survived looking good for centuries because its builders spent 70% of their efforts on things you can’t see, underground and inside.