Drawing a Site Plan Autocad Helping Forum

Drawing a Site Plan

The site plan you will use has been simplified so that you can draw it with a minimum of steps and get on with the external referencing. The following are essential elements:

  • Property line

  • Access road to the site

  • North arrow

  • Indication of where the building is located on the site

The first step is to draw in the property lines.

Using Surveyor Units

You draw property lines using Surveyor units for angles and decimal feet for Linear units. In laying out the property lines, you will use relative polar coordinates, so you will enter coordinates in the format @distance<angle, in which the distance is in feet and hundredths of a foot, and the angle is in Surveyor units to the nearest minute.

Surveyor Units

Surveyor units, called in civil engineering, describe the direction of a line from its beginning point. The direction (bearing), described as a deviation from the north or south toward the east or west, is given as an angular measurement in degrees, minutes, and seconds. The angles used in a bearing can never be greater than 90°, so bearing lines must be headed in one of the four directional quadrants: northeasterly, northwesterly, southeasterly, or southwesterly. If north is set to be at the top of a plot plan, south is down, east is to the right, and west is to the left. Thus, when a line from its beginning goes up and to the right, it is headed in a northeasterly direction. And when a line from its beginning goes down and to the left, it is headed in a southwesterly direction, and so on. A line that is headed in a northeasterly direction with a deviation from true north of 30 degrees and 30 minutes is shown as N30d30' E in AutoCAD notation.

With the Surveyor unit system, a sloping line that has an up-and-to-the-left direction would have a down-and-to-the-right direction if you started from the opposite end. So in laying out property lines, it is important to move in the same direction (clockwise or counterclockwise) as you progress from one segment to the next.

Laying Out the Property Lines

You will set up a new drawing and then start at the upper-right corner of the property lines and work your way around counterclockwise.

  1. Open Cabin11a from your training folder. Choose File Ø Save As, and save the drawing as Cabin12a.

  2. Click the QNew button on the Standard toolbar to open the Create New Drawing dialog box. Click Start From Scratch, and then click OK. (If the Select Template dialog box opens instead of the Create New Drawing dialog box, open the Open drop-down list and select Open With No Template - Imperial.)

  3. From the menu bar, choose Format Ø Units to open the Drawing Units dialog box, and change the precision in the Length area to two decimal places (0.00).

  4. In the Angle area, open the Type drop-down list and select Surveyor’s Units. Then change the precision to the nearest minute (N0d00' E). Click OK. You will need an area of about 250' ´ 150' for the site plan.

  5. Open the Format menu again and choose Drawing Limits. Press ¿ to accept the default 0.00,0.00 for the lower-left corner. Type 250,150¿. Don’t use the foot sign.

    We are using Decimal linear units in such a way that 1 decimal unit represents 1 foot. The foot symbol (') is used only with Architectural and Engineering units.

  6. Right-click the Snap button on the status bar, and then choose Settings. Change Snap Spacing to 10.00, and change Grid to 0.00. Then click the Grid check box to turn on the grid, but leave Snap off. Click OK.

  7. In the drawing, type z¿ a¿. Then zoom to .85x to see a blank space around the grid (see

  8. Create a new layer called Prop_line. Assign it a color and make it current.

  9. Start the Line command. For the first point, type 220,130¿. This will start a line near the upper-right corner of the grid.

  10. Be sure Snap is turned off. Then type: @140<n90dw¿

    @90<s42d30'w¿

    @140<s67d30'e¿

    @80<n52d49'e¿

    c¿

The property lines are completed (


Figure 12.3: The property lines on the site drawing

Drawing the Driveway

The driveway is 8' wide and set 5' from the horizontal property line. The access road is 8' from the parallel property line. The intersection of the access road line and the driveway lines forms corners, each with a 3' radius. The driveway extends 70' in from the upper-right corner of the property.

Let’s lay this out now.

  1. Choose Format Ø Units from the menu bar. Change the units to Architectural and the angular units to Decimal degrees. Then set the length precision to 1/16" and the angular precision to 0.00. Click OK. Because of the way AutoCAD translates decimal units to inches, your drawing is now only 112th the size it needs to be. (Use the Distance command to check it.) You will have to scale it up.

  2. Click the Scale button on the Modify toolbar.

    You can also start the Scale command by choosing Modify Ø Scale from the menu bar or by typing sc¿.

  3. Type all¿¿. For the base point, type 0,0¿.

  4. At the Specify scale factor or [Reference]: prompt, type 12¿. Then click Grid on the status bar to turn off the grid.

  5. Zoom to Extents, and then zoom out a little. The drawing looks the same, but now it’s the correct size. Check it with the Distance command, which you encountered in

  6. Offset the upper, horizontal property line 5' down. Offset this new line 8' down.

  7. Offset the rightmost property line 8' to the right

  8. Create a new layer called Road. Assign it the color White, and make the Road layer current.

  9. Click the new lines, open the Layer Control drop-down list, and click the Road layer to move the selected lines to the Road layer. Press Esc to remove the grips.

  10. Extend the driveway lines to the access road line. Trim the access road line between the driveway lines.

  11. Fillet the two corners where the driveway meets the road, using a 3' radius


    Figure 12.4: Offset property lines (a), and the completed intersection of the driveway and access road (b)

Finishing the Driveway

A key element of any site plan is information that shows how the building is positioned on the site relative to the property lines. Property lines are staked out by surveyors. The building contractor then takes measurements off the stakes to locate one or two corners of the building. In this site, you need only one corner because we are assuming the cabin is facing due west. A close look at , shown earlier in this chapter, shows that the end of the driveway lines up with the outer edge of the back step of the cabin. Below the driveway is a square patio, and its bottom edge lines up with the bottom edge of the back step. So the bottom corner of the back step coincides with the lower-left corner of the patio. This locates the cabin on the site (


Figure 12.5: The driveway and patio lined up with the cabin

Imagine the site being on a bluff of a hill overlooking land that falls away to the south and west, providing a spectacular view in that direction. To accommodate this view, we will want to change the orientation of the cabin when we Xref it into the site drawing.

  1. On the status bar, turn on Polar. Then draw a line from the upper-right corner of the property lines straight up to a point near the top of the screen.

  2. Offset this line 70' to the left. This will mark the end of the driveway.

  3. Draw a line from the lower endpoint of this offset line down a distance of 40'-4". Then, using Polar Tracking, continue this line 11'-4" to the right.

  4. Offset the 40'-4" line 11'-4" to the right. Offset the newly created line 11'-4" to the right as well.

  5. Offset the upper driveway line 24' down. These are all the lines you need to finish the site plan


    Figure 12.6: The offset lines (a), and the finished driveway and patio (b)

  6. Finish the driveway and patio by using the Trim, Fillet, and Erase commands as you have in previous chapters. The radius of the corner to fillet is 6' (

  7. Make the 0 layer current, draw a north arrow, and place it in the lower-left corner.

  8. Open the Layer Properties Manager dialog box, and change the linetype for the Prop_line layer to Phantom. (You will have to load it; see

  9. Type ltscale¿, and then type 100¿. You will see the phantom linetype for the property lines.

  10. Save this drawing in your training folder as Site12a.