Moisture in the screed can severely affect the quality of your floor and even lead to structural damage. In this blog, we will delve deeper into the causes of moisture problems, offer effective solutions, and provide useful tips to prevent and address these issues.
What are possible causes of a damp screed?
A damp screed can be caused by various factors, often leading to structural problems and health risks such as mold formation. A common cause is rising damp, where groundwater rises through the foundation and walls, eventually reaching the screed. Leaky pipes, such as poorly installed water pipes or underfloor heating systems, can also cause moisture problems. Additionally, condensation moisture can occur in poorly ventilated areas, where humid air condenses on cold surfaces and penetrates the screed. Finally, penetrating damp, where water seeps through walls due to rain or poor external sealing, can spread to the screed and make it damp. Identifying the specific cause is crucial for an effective solution.
What to do in case of rising damp?
Of course, the solution depends on the specific situation and the diagnosis made. Installing a moisture barrier between the foundation and the walls can prevent moisture from rising from the ground, also known as rising damp. Apply a moisture barrier before you actually lay the floor.
What is a moisture barrier?
A moisture barrier is a waterproof barrier applied under the floor to prevent moisture from the subfloor from penetrating the floor.
What types of moisture barriers are there?
There are various types of moisture barriers that effectively protect against moisture problems in the floor. Here are some important types:
PE film
Polyethylene (PE) film is the most commonly used form of moisture barrier. These plastic rolls provide an excellent vapor-proof layer, ideal for use with underfloor heating. For example, take a look at this moisture barrier film.
Other films
In addition to PE film, there are other films such as Alufoam, Isogold, and Blue Line Heat+, which are both moisture-resistant and sound-reducing. These must be properly taped to maintain their effectiveness.
Primers
Epoxy-based primers, such as UZIN PE 460 and UZIN PE 400, also serve as a moisture barrier. They are applied directly to the subfloor and provide a strong barrier against moisture. You often see these being applied before leveling for glue-down PVC floors.
