Does my property have a damp proof course?
How do I know if I have a damp proof course?
Rising damp is the movement from the ground of moisture through walls and floors by capillary action. Depending upon site conditions, it can rise to 1m or more in walls. There is usually a ‘tide mark’ and sometimes the appearance of white salts. To avoid this buildings are constructed with a damp proof course.
The UK Public Health Act of 1875 made it compulsory to provide the walls of a building with a damp proof course. Although it is reported that this new requirement was slow to catch on. During the early years designers experimented with various types of materials to provide a damp proof course such as slate, engineering brick, lead or bitumen mixed with mortar. These earlier damp proof courses tend to be more unreliable. Bitumen felt damp proof courses are the most common type found in older properties and was used mainly between the 1920’s and 1980’s. As technology advanced polythene strip damp proof courses were used from the 1970’s and are now the most common type of damp proof course in new construction.
Slate damp proof course
When carrying out surveys we often see the edge of the slate damp proof course, particularly in Victorian properties, with asphalt being seen in more modern properties of the 1930’s. Moving on to buildings from the 1970’s to present day where the familiar plastic strip is visible.
In Conclusion. Most houses from the 1920’s on have some form of a damp proof course. The particular type of damp proof course is sometimes visible especially in brick houses. However many buildings have new additions and are often plastered which makes it harder to see. If you spend a little time inspecting the lower walls of any building you have a good chance of identifying if there is a damp proof course. This is really useful if you are experiencing damp related issues as it allows you to see if there are instances of bridging etc.
Polyethylene damp proof course
Asphalt damp proof course
The post How do I know if I have a damp proof course? appeared first on Mould Removal, Woodworm Treatment, Rising Damp tips from across the web!!.
