How to Distinguish Between Rising and Penetrating Damp

18 December 2019
 Categories: , Blog

Many older homes feature a basement that may have been used as a storage facility over the years. Due to some expansion plans, however, some people may decide to take advantage of the space and may plan to renovate it so that they can add a functional room for their growing family. Unfortunately, they may find a certain amount of deterioration and water damage that appears to be pervasive. In this case, they will want to know if they are suffering from rising damp or penetrative damp before they proceed.

Rising Damp

Rising damp is principally caused by moisture that is able to permeate through the masonry from ground level, where a damp-proof course may have deteriorated or may not have been installed in the first place. The moisture will rise up slowly and, as it goes, will deposit fluoride and nitrate which will be leached out of the soil. This will leave a tell-tale mark at the furthest extent of the damp penetration, and it'll certainly stain any paintwork or wallpaper, often permanently. With this type of damp penetration, you can also expect to find rotten wood, skirting boards, floor timbers and other components that may be in a considerable state of disrepair.

Penetrating Damp

Penetrating damp, on the other hand, will typically seep through into the wall from moisture that is pressing against the external walls. This is particularly common in basements where the outside wall is completely or partially covered by soil and where the moisture has been able to penetrate the fabric of the wall itself. This is known as lateral damage, while vertical penetrating damp is typically caused by defects in the guttering system.

Dealing with the Problem

To treat these issues effectively, contractors will need to address the source of the problem. They will need to put a damp-proof course in between the soil and the wall in question and get rid of any part of the structure that may have been damaged beyond repair. This will typically include all the rotten wood, rendering, plaster, paint or wallpaper, and the area must be allowed to dry completely before any renovation work can go ahead.

Expert Analysis

Before you determine what type of rising damp treatment you need, bring in the experts first. They will have seen this type of damage before and will be able to identify its characteristics so they can put in place an appropriate plan to move forward.