Retaining Walls, Sharps Chapel, TN
Sherry and Greg contacted us in late spring of 2015. They had recently purchased a home on beautiful Norris Lake and were looking to replace a failing landscape. The modern brick house sits atop a steep point that extends into the lake below. The meager structural retention built by the previous owner consisted of a hodge-podge of 3”x3” timbers and rebar terraced precariously below the south face of the home. (See picture below). The whole affair was failing, unattractive and dangerous. The site was steep and largely inaccessible. The soils were shaley and nutrient poor. In addition, all retaining wall designs needed to accommodate a four-wheeler route to the dock below. To complicate matters further there were trees on the slope, and utility and drainage lines buried beneath.
After two head-scratching site visits, a great deal of discussion and a couple of scheduling delays we arrived in August with an initial 24 tons of TN field stone, followed by eighteen 48″x18”x7” Crab Orchard steppers. We were finally underway.
Excavating for a Firm Footing
There was really no way to determine our footing depth without destabilizing the existing timber scape so it was decided that the demolition of the timbers would happen in phases as the wall moved up the slope. Because of the steepness of the site the footing the retaining walls required “stair-stepping” to distribute the weight and gravitational forces of the wall. Initially this presented no serious dilemmas.
The first two wall sections and stairs went in fairly smoothly from a masonry perspective. However, we managed to hit buried well lines, located in an area they were not supposed to be. To make matters worse Sherry had broken her foot the weekend after we arrived and was in no position to be without water. It was a tough couple of days.
The third section of wall provided a further setback. The fill material from the original house construction was deeper as we moved up the grade. Thus, we were forced to dig deeper footings to locate solid “native” soil underneath. Consequently, the height and width of wall needed to increase from 40 inches to six feet – no small amount when constructing a dry-laid field stone wall. To complicate matters there were buried drain lines that needed to be relocated below the wall footing. A deeper footing meant considerably more excavation to re-install them. Even with the lines neatly buried 7 feet below grade we were forced to bridge the 4” PVC lines with wide scarcements behind the wall.
For ten days we labored in the 90-degree heat beneath the steep cut, meticulously breaking, chiseling and setting stone. Finally, by the end of August, the completion of the enormous lower wall was in sight. Thankfully, we found solid footing material at shallower depths as we proceeded up the slope. We also moved into the shade a bit – our seven gallons a day water habit dropped to five.
Completing Lower Wall, Starting Upper Wall
With a second load of rock arriving the first week of September we were able to complete the 90’ lower wall and move on to the curved upper wall. With better access to our materials and stable footing we began to speed up the pace. We laid nearly 120 square feet in the first two days of construction on the upper wall! – surely a company record. Within five days it was clear we would need a third small load of stone. In late September the final four 2-ton baskets of rock arrived and it was time to put the finishing touches on. The process went smoothly and the upper wall was extended to accommodate a small stairway and return.
A wall section was added below to support a questionable slope and deck footing. A short wall and pocket garden was added to “lift the grade” in front of the upper wall and improve the entrance to the deck. Finally, fifteen tons of topsoil and mulch were backfilled behind the upper wall for plantings. Twenty-seven finger boulders were carefully placed to substantiate various points of interest, road bond was spread for Greg’s four-wheeler path and re-vegetation was complete….and did I mention the unsightly Virginia pines removed by V&V tree personnel to improve the gorgeous lake view?
All told the project required a whopping 270 plus thousand pounds of material – nearly all of which was placed by hand.
The Retaining Wall Increased the Appeal, Equity and Stability of the House
We would like to extend our gratitude to the Sherry and Greg who so generously accommodated us in every way. Even when things were down they supplied ample amounts of gratitude, support and delicious food. (Anyone who takes both my mother and mother-in-law for a pontoon ride deserves special recognition). Thanks also to fellow staff members: senior mason Jon LaGrant and junior masons Ethan Blackwelder and Aaryn Williams. You guys would indeed make an excellent prison crew.