Case Study: An Elevated Structural Stone Patio in Fairfax
An elevated patio looks like stonework, but underneath it is a structural concrete build. This one, at a home in Fairfax, Virginia, in Fairfax County, is built completely structural: footings the whole way around, block built up from them, rebar tied 24 inches on center across the whole slab, and piers anchoring the section built into the hill, with a step system down to grade. On top of that structure goes the stone: Tundra Gray marble on the patio, with a thick 2-inch bullnose edge around the whole perimeter, on every seating wall and on every step, and Coyote ledge-cut natural stone on the wall faces. A low-voltage landscape lighting design and a couple of outdoor outlets finish it for use after dark.
The build on video: we are filming this patio stage by stage, and the footage will be posted here as the job comes together:
- The rebar prepped.
- Block and gravel ready for the slab pour, with a close look at the rebar.
- Midway: the concrete and block before the stone goes on.
- Completion: the finished stone and lighting.
In the meantime, see our work on the Tuck GC YouTube channel.
| Project at a Glance | Details |
|---|---|
| Location | Fairfax, VA (Fairfax County) |
| Structure | Footings the whole way around, block buildup, gravel base, rebar tied 24 in. on center across the slab, corner piers 3 ft below the footer in the hillside section, step system |
| Stone | Tundra Gray marble patio with a thick 2-inch bullnose on the full perimeter, all seating walls and all steps; Coyote ledge-cut natural stone on the wall faces |
| Lighting | Low-voltage landscape lighting design; a couple of outdoor outlets |
The Structure: Footings, Piers and an Elevated Slab
The stone is only as good as what is under it. An elevated patio puts a heavy slab, heavy stone and people several feet off the ground, and that load has to reach soil that can carry it. Here is how the structure goes together:
- Footings the Whole Way Around Footings run the full perimeter of the patio. We excavate below the local frost line, to the depth and size the approved plans and soil conditions call for, and pour the concrete footings on load-bearing soil.
- Block Built Up From the Footings Concrete block walls are built up from the footings to the height of the patio, and the inside is prepped with gravel ahead of the slab pour.
- Rebar Tied 24 Inches On Center Rebar is tied off 24 inches on center across the whole slab before the pour, so the slab goes in as one reinforced structure on the block and footings.
- Piers Where the Patio Meets the Hill Part of the patio is not elevated; it is built into a big hill. There, the bottom of the footer sits 30 inches below the top of the slab, and at each corner a pier goes down another 3 feet below the footer.
- The Step System The steps down to the yard are built as part of the same structure, not added on afterward.
Why build it this way? Because we see what happens when it is not. We recently rebuilt a failed elevated garage slab in Annandale: the builder never properly backfilled, the slab sat on loose fill with nothing structural under its middle, and the center failed. On this patio, every part sits on footings, block and a rebar-tied slab.
The Stone: Tundra Gray Marble and Coyote Ledge-Cut
Once the structure is in, the stonework starts. The Tundra Gray marble is wet-set in a full mortar bed on the structural slab. A full bed matters because hollow spots are where wet-set stone cracks under point loads. A thick 2-inch Tundra Gray bullnose, a rounded finished edge, runs around the entire perimeter of the patio and along every seating wall and step, so every exposed edge reads as solid stone. The wall faces get Coyote ledge-cut natural stone. On concrete or masonry surfaces we install the veneer over metal lath, which gives the mortar a mechanical key so the stone is anchored to the wall, not just glued to the surface; a Type-S mortar scratch coat goes over the lath, and each stone is hand-set into a fresh mortar bed.
See more of this work on our marble and travertine patios, stone seating walls, stone veneer and stone steps pages.
Lighting and Power
The project includes a low-voltage landscape lighting design for the patio, the seating walls and the steps. Lighting the steps makes them safer to use at night, and lighting the walls and stone faces lets the patio be enjoyed after dark. The plan also includes a couple of outdoor outlets.
Permits and Engineering
An elevated patio with footings, piers and a structural slab is structural work, and Fairfax County and the surrounding jurisdictions generally require a building permit and inspections for it. Tuck GC is a Class A (RBC) Virginia contractor. Where the design needs a stamp, we coordinate a licensed Professional Engineer and build to the stamped plan; we do not do the engineering in-house.
Elevated Patio FAQ
Footings, block and steel. On this Fairfax patio, footings run the whole way around, block walls are built up from them, and rebar is tied 24 inches on center across the whole slab; where the patio is built into the hill, piers go down another 3 feet below the footer at each corner. Compare that with a slab poured on loose fill with nothing structural under its middle, which is how the Annandale garage slab we rebuilt failed.
Yes. The structural slab is the base, and the stone is wet-set on it in a full mortar bed. On this Fairfax patio the surface, perimeter bullnose, seating walls and steps are Tundra Gray marble, with Coyote ledge-cut natural stone on the wall faces.
An elevated patio with footings, piers and a structural slab is structural work, and Fairfax County and the surrounding jurisdictions generally require a building permit and inspections for it. Where the design needs a stamp, we coordinate a licensed Professional Engineer and build to the stamped plan.
Yes. This project includes a low-voltage landscape lighting design for the patio, steps and seating walls, plus a couple of outdoor outlets.
Plan Your Elevated Patio
If your yard drops away from the house, an elevated patio can give you a level outdoor room off the back door. Call 703-540-1000 or reach us through the contact page, and we will walk the site and talk through the structure before the stone.