The first step in foundation construction is precise surveying. To stake the foundation position for a rectangular house correctly, we have to construct a right angle.

Hammer in the first stake and mark a right angle obtained by means of an angle. Measure out a length of rope to find out the position of the centres of other foundations, or other important points, for example the building corners.

A right angle is obtained by building a simple angle of boards or stakes. A right angle occurs in a triangle where the sides are in a 5:4:3 proportion. A common multiple will help us reach practical dimensions of the tool. Some practical dimensions are indicated in the figure.

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The next step is adding the remaining points. For an orthogonal rectangular shape with side lengths (a) and (b), as in the figure, we can check using the diagonals and any imperfections in the surveying can be rectified. The diagonal lengths, (c), should be identical. In the case of a square shape, the diagonals should even be perpendicular to each other.

Another possible step is constructing so-called benches. These are used to mark distances with a line. The stakes can then be removed and we can start working on the foundations. If necessary, ropes can be tied to the nails in the benches again to check precision of your construction work.

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Before the concrete mix sets, the positions of the metal anchors to which the fundamental loadbearing flooring will be fastened, must be finalised. Again, the precise locations according to the plans can be detected from the positions already marked on the auxiliary structures – benches. The final surveying must be checked properly as the bench positions can sometimes be disturbed during construction work.