Mechanical / Physical Damp Proofing Solutions

This is the oldest method. The mechanical or physical damp proofing solutions attempt to insert a new damp proof course into the masonry. The wall is drilled or cut-through horizontally and a new solid damp proof course is inserted into the gap.

Several such technologies have been developed, the most important ones are the following:

- Wall substitution: several layers of bricks in the base area are replaced by new material, and a new damp proof course is also inserted.

- Metal plates insertion:  the wall is cut through horizontally in its length with a diamond chainsaw and special chromium-nickel-molybdenum steel plates are shot into the brickwork.

metal plates

Metal plates insertion


- Drill core procedure
: 8-10 cm diameter holes are drilled alternatively into the wall base, then the holes are filled with waterproof concrete.

drill core

Drill core procedure

These mechanical procedures are not widely used in the UK.


Advantages

- If done right, physical damp proof courses can last a long time and give full protection.

Disadvantages

- Very noisy, labor intensive and costly.

- Severely interferes with the structure of the building, high level of shocks and vibrations.

- High risk of settlement cracks especially at the window or door frames as the masonry might skid on the metal plates.

- Metal plates insertion is not suitable for certain types of houses, such as stone masonry (the plates must be horizontal), houses on the hillside or for walls with lateral stress.

- Corrosion: ground salts can corrode some metal plates and changing the sheets thereafter can be a major problem.

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