Garden Survey – Measuring the Footprint of Your House
- Start by measuring the footprint of your house. Using one of your ground-pegs to anchor it, peg the end of your tape measure down securely and run it along the facade of the building. Take running measurements at each feature – windows, doors etc – and write them on your survey drawing
- Do this on all sides of your house that are relevant to your garden design
- Where a house has an angle other than 90°, take an offset to the corners from established points. The angle can be checked by assuming a triangle between it and a house corner on either side, and by measuring all three sides.
- Measure from the sides of the house to the boundary.
Garden Survey -Triangulating Boundary Points
Even if the site looks square or regular, use the triangulation technique to position the boundary corners as a check:
- Measure from one corner of the house to the point you want to fix, and then measure to it from another corner.
- Clearly note the measurements.
- Make a wide triangle: if too narrow, it will not be accurate when you transfer the measurement from the survey sketch to the scale plan.
- Then measure around the boundary, noting where fence becomes wall, wall becomes hedge, where the gates occur and so on.
The triangulation technique also enables you to position trees and other elements accurately:
Garden Survey – Triangulating Trees.
Measure from the trunk of each tree to two corners of the house, for clarity noting the measurements on a separate sheet if necessary.
- It is important to measure the spread of each tree, too, remembering that it may not have grown evenly.
- All tree canopies should be drawn to scale on your plan to avoid mistakes with planting schemes.
Garden Survey – Taking Offsets
Some rectangular sites, and some areas of gardens of any shape, can be measured up simply by taking offsets at 90° to the house:
- Peg the end of the tape down securely at a known point (mark the position of the peg on your survey sketch), then run the tape up the garden at right angles to the house or other known feature.
- Wherever a feature intercepts the tape, write down the measurement.
- With a second tape, take offsets at 90° to the first tape, measuring across to trees or other features in the garden.
Garden Survey – Measuring Curves
- Establish a line for the tape that is parallel or at right angles to a known feature.
- Measure to the curve at regular intervals – say every 500 mm.
- Use this technique in reverse for pegging out on site a new feature that you have designed.
Garden Survey – Measuring Levels
- Use two wooden stakes and a lath of wood with a measure – say 1 metre marked off on it:
- At the top of slope lay the plank down, and use the mark on it to position a peg 1 metre below.
- Hammer in the peg until the plank is level when its end is placed on the peg (check this with a spirit level)
- Measure the amount of peg above the ground – this gives you the total fall over 1 metre.
- Continue down the slope using both pegs to rest the plank on and checking for level each time; the fall is the height of the lower peg minus that of the higher one.
- Add together the falls to get the total fall in the ground over however many metres you have measured.
Alternative Method for Gentle Garden Slopes
This method is is not strictly accurate, but it can be useful if all you need is a general indication of a change of level:
- Ask someone to stand at the top of the grade and hold a length of string out until it is horizontal, using a spirit level held along the string to check.
- With your tape measure from your end of the string to the ground to find the total change of level. You may need a couple of helpers to do this.
Locating Other Features to Use in Your Design
Sketch individual areas on separate sheets so you have room for the figures that you need to record on your survey, using the techniques on this page. Measure paving stones, threshold details, and so on. Take vertical measurements too; the height of the existing hedge, for instance.