Oakum
Oakum can be used to seal cast iron pipe drains. After setting the pipes together, workers pack oakum into the joints, then pour molten lead into the joint to create a permanent seal. The oakum swells and seals the joint, the "tar" in the oakum prevents rot, and the lead keeps the joint physically tight.
Today, modern methods, such as rubber seals (for example, gaskets or o-rings) are more common.
Tie (cavity wall)
Due to its materiality of the tie, its corrosion is related to the extent of the exposure at acidic substances. The major factors of the corrosion is these:The cement-based mortar, giving an alkaline environment for cavity wall ties, has been used after World War II. Alkaline environment is beneficial for ties protecting from acid and procrastinating the corrosion process. Before cement-based mortar, lime-based one was used, which does not present an alkaline environment. Therefore, the majority buildings with wall tie corrosion are built before World War II. An alkaline degree gets weaker while exposed at acidic rain over the time.