Between a rock and custom design
The primary locus of this column over the past few months has been on adding special features such as swim-up bars, caves and all-tile surfaces to your pools and spas.
But not all custom features are as complex as these. To illustrate how quickly and easily you can distinguish your design work, let's focus here on three different ways to bring rock work into a backyard poolscape.
Rock waterline and coping
Using rockwork as your "tile" line and coping is not a difficult process, and yet it can add a custom touch to your work that customers will truly appreciate.
If your clients do decide they want to include rockwork along their pool's edge, the first thing you'll need to determine is how much rock waterline, the rock face is normally ½ to ¾ of a square foot.
Though it scrves as a "tile" line, rock of this size obviously cannot be adhered to the pool structure in the same way tile is. To prepare a secure seat for the rock, you must cut a notch along the pool's edge right after guniting. The base of this notch usually extends 3 to 4 inches below water level, but the depth will vary depending on the size of the rocks selected by your clients.
A caution: Special attention should be taken during the forming and steel stages of construction to ensure that the notch you cut in the gunite shell will not compromise the integrity of the bond beam. Before placing the rock in its waterline perch, the entire notch area also must be waterproofed.
For the best effect, you should try to match the pool coping whit the type of rock used at the waterline. If you choose to use rock coping, however, it can be difficult to butt decking against it.The solution here is simple: Take this opportunity to design planting areas next to the pool - and further distinguish your design from the run-of-the-mill.
Including a large rock in a poolscape can be purely acsthetic or funcional. But if the rock is to serve as a diving platform , for acsthetic reasons it should be placed partially in the water, rather than on top a rile line.
Not surprisingly, placing a large rock inside the normal pool perimeter requires slighty more effort than using rock as a waterline feature, although the principle of the rock notch is the same.
Let's use an extreme case as an exemple: Your clients would like a 6-foot-long rock in their pool, and you must provide a ledge (or notch) for this rock to sit on safely, If the rock over hangs the water excessively, however, you will create an unsafe condition. So the idea here is for the rock to appear to overhang but to actually have structutal support that prohibits bathers from swimming under it.
If you visualize the notch required as a shallow loveseat - whit, say 3 to 4 inches of water in it - you can see how this look can be accomplished. And such a ledge can be constructed to any size necessary.
As pool, contractors who regularly use large rocks in their installations are aware, these projects can generate some additional cost. Many require material-handling equipment to place the rock, for example, so don't forget to allow for this cost in your bid.
"Rack back" waterline
If your customers want their pool to appear as thought it sits next to a hillside outcropping, consider adding a "rack back" detail to your pool design. This king of detail provides a much more natural look than can be accomplished by setting rock vertically along the pool waterline.
In this design, rock is shingled back from the pool's edge, with rocks placed on top of other so that each higher rock sits farther back from the water. You and your client can select any size boulders for this detail, but remember that the larger the material, the greater the expense.
The pre-guinte work necessary for this feature is more extensive than the standard waterline-rock detail. You start by calculating the finished height of the beam for the finished height of the beam for the rock area. If it's 12 inches above the normal pool beam, for example, you would need o move the form back at least one additional foot. You can move the form back even farther to get a more material you will need to do the masonry work.
To hold the rocks in place properly, the notch you carve in the gunite notch should be at an angle, stretching from the top of the raised area to where it intersects with the vertical pool wall (Again, the notch should hit the pool wall 3 to 4 inches below the waterline.)
For all this extra work and expense, there is one key advantage to working with a "rack back" design that you can offer clients: It opens up the possibility of including waterfalls or weeping rock faces at minimal additional cost.
Unfortunately many pool builders avoid the use of natural materials in this or any other detail because of the increased difficulty- and expense- they bring to the construction process.
If you ask the builders who do work with rock why they bother, however, they'll worth all the trouble.