Landscaping For Dummies. Lance Walheim

Laying Out Straight Lines and Shapes

      A layout is a system of stakes and stringlines that establishes the precise location of footings and borders for a building project. This could be the perimeter of your dream deck or patio, or just a fenceline.

      You normally do layout after grading the site (see the previous section), but you may need to set a few stakes, using basic layout techniques, to guide the grading. Yes, doing so sounds old-school, but the methods are tried-and-true, and you can do it.

If an obstacle, such as a tree trunk, makes it impossible to string a line between two stakes, move both stakes an equal distance, in the same direction, from their original position. Then, stretch a stringline between them. To establish points, such as post locations, where the original stringline would have run, measure an equal distance from the string to the distance that you moved the stakes. This technique is called offsetting.

       Make sure that you establish precisely what the stringline represents, for example, the inside edge of posts, the outside edge of the finished structure, the center of footings — whatever. It doesn’t matter what you choose; just be consistent. Usually, however, stringlines represent the outside edges.

       Any sturdy string will do for these tasks, but we recommend mason’s twine because it is more durable and stretches less.

      These sections help you execute these tasks in your yard. We prefer to use basic and practical techniques that many construction surveyors use on a regular basis.

      Stringing lines — The hub and tack method

      The simplest example of a layout is a string stretched between two stakes to establish a straight line. Instead of tying the line to the stakes, we recommend the more accurate method of securing the string to nails in the top of each stake. In construction surveying’s lingo, this is called the hub and tack method; that is, the stake is a hub and the nail is a tack.

Here’s how to do get started for a fence or a square or rectangular patio or deck or even a pathway (refer to Figure 4-2):

      1 With a sledgehammer, pound 18-inch (45.7 cm) stakes 6 to 12 inches (15.2 to 30.5 cm) into the ground at each end of the proposed line.

      2 Pound in a small nail at the top, in the center, of each stake — only partway.

      3 Tie a string from one nail to the other.

      Stringing out the rest of a shape

After you establish the first line, finish stringing the perimeter of the rest, whether it’s your new patio, deck, or another item. Just follow these steps:

      © John Wiley & Sons, Inc.

      FIGURE 4-2: Lay out a line.

      1 To establish a right angle and thus continue laying out the shape, go down your existing line 3 feet (.9 m) and set a stake.Using a carpenter’s square, go 4 feet (1.2 m) down in the perpendicular direction and set another stake. Put nails on top of each, as you did when you laid out the initial line.

      2 Measure the diagonal between the two new stakes.If it’s 5 feet (1.5 m), you’re good, you made a right angle (you have a good carpenter’s square). If it isn’t, adjust the stake on the line that lacks a string yet (the one 4 feet, 1.2 m away) until it all checks out, that is, the numbers form a triangle with a right angle. For checking larger distances, use multiples of 3, 4, and 5 feet, such as 9, 12, and 15, or 12, 16, and 20 feet (in metric, that would be .9, 1.2, and 1.5 m, such as 2.7, 3.6, and 4.8 m, or 3.6, 4.9, and 6.1 m).

      3 Continue down your new line the designed/desired distance, and put in another stake at the end, again topping it with a partially pounded-in nail.Run mason’s twine the full length.

      4 Double-check your diagonals.This step requires math. Get out a calculator. We deploy the Pythagorean Theorem. (Yes, this is your tenth grade trigonometry class, back to haunt you!):a2 + b2 should = c2a is the length of one side, b is the length of the other side, and c is the diagonal distance between the corners.Adjust the stakes until it all checks out. In some situations, such as attaching a deck or patio to the house, your layout may look cockeyed because the house walls, driveway, or other existing features aren’t square. If so, fudge the layout slightly to bring the side of the layout in line with the existing feature.

      5 When you’re satisfied, mark the layout on the ground.If the stringlines are for guiding excavation — for fence posts or a patio base, for example — you need to mark the ground for digging. Where such marks must be perfectly accurate, hold a plumb bob close to the ground, with its string brushing against the stringline, and mark the ground directly under the bob with spray paint, flour, chalk, or colored cloth held down with a nail. Make several marks, as needed.

Working with Slopes

      Installing one or more retaining walls on a slope does two good things for a landscape:

       It prevents erosion.

       It creates flat plantable areas where there wasn’t before.

      You can build a low (3 feet, .9 m, or less) retaining wall yourself out of timbers, stacked stone, or stacked block using the techniques in these sections.

       A wall higher than 3 or 4 feet (.9 or 1.2 m) is more of an engineering feat than a low one (it has to be able to withstand the considerable pressure from the earth behind it). It generally requires permits. Have a professional — a landscape architect or a stonemason, depending the material — design and build it.

      Understanding challenges unique to installing retaining walls

      Be prepared to contend with these major issues when you’re installing retaining walls (they’re certainly not deal-breakers when your wall is 3 feet (.9 m) or less):

       It’s hard work. Even for a wall of low height, you have to dig a lot. Depending on the materials you choose, you’ll also be doing heavy lifting and maneuvering — all the more so if you plan several successive ones, that is, if you’re terracing a slope (see the nearby sidebar about terracing).TERRACING DEMYSTIFIEDTerracing is a great solution for turning an otherwise unusable or difficult-to-landscape slope or hillside into garden space. Just fill the completed terraces with soil and plant away. Or, customize the soil in each one — we’ve seen some great rock gardens on this plan. (For rock-garden information, turn to Chapter 20.) Because you’d still be scrambling up and down a hillside to care for whatever plants you install, we recommend low-maintenance choices. Check the color insert for a photograph of how one homeowner worked terracing into their landscape.Remember: One 3-foot (.9 m) retaining wall is a retaining wall; installing a succession of two or more is basically terracing. It’s the same project as the ones we describe in the section, “Working with Slopes,” in this chapter, just bigger. You’ll do more measuring, more excavating, devote more time, and spend more money on materials.Before you start the project, you need to establish a plan