On the left exterior wall, water penetrates the wall from underneath and laterally, damp rises to a higher point than in the middle wall where water penetrates only from underneath. On the right exterior wall, vertical sealing was applied (here, bitumen layer with protective foil) and a drainage pipe was installed. Therefore, damp cannot penetrate laterally, but the wall remains damp due to the penetration of rising damp from underneath.

The right wall acts as a detached wall due to vertical sealing: the drying effect by the GUARDIAN damp removal is complete, the same as with the middle wall. In the case of the left exterior wall, the effect would be reduced due to the lateral water penetration. In most cases, the interior side of the walls would be dry, but the concentration of dampness would be increasing towards the exterior side of the walls. It depends on the soil conditions.

Due to the heavy lateral pressure of water, exterior walls are completely waterlogged and it is absolutely necessary to perform the vertical sealing in order to achieve the full drying effect by the use of the GUARDIAN damp removal. The water pressure should be removed from the house; therefore, in addition, drainage can be performed at the lower edge of the object.

In this example, this has been done on the right exterior wall; therefore, it is less wet than the left unprotected wall. In this way, the right wall is exposed to rising damp only from beneath. Since the lateral water pressure is no longer affecting the right exterior wall, the GUARDIAN damp removal can remove the damp completely. On the other hand, the left unprotected wall will be dry only to the level of the slope whereas the part of the wall in the ground will remain damp. The vertical sealing should always be performed by a specialised company in order to be certain that the damp does not penetrate the wall few years later, due to the vertical sealing losing its effect.