Amidst so many systems and types of waterproofing available in the market, it is very common that engineers and architects get a little confused when it comes to choosing the best option. After all, this is a very specific subject - and it takes a lot of experience to master it.
Waterproofing is an essential part of the project, being regulated by several NBR. To help you, I made a complete post for you, showing the main systems and types of waterproofing agents. Check it out!
What are the 2 main types of waterproofing?
In general, there are two types of waterproofing on the market: rigid and flexible. The use will depend exclusively on the characteristics of the structures and the materials in which they will be applied. In other words, it is not a choice per se: if a certain surface requires flexible waterproofing, only it can be used.
For this reason, one of the most important steps in the elaboration of a project is to list the requirements of each part in relation to the type of waterproofing.
1. rigid waterproofing
It is suitable for structures that are not subjected to large movements. In addition, they cannot be exposed to mechanical stress, which can be caused by intense vibrations or constant impacts.
Generally, it is done with the application of chemical additives in mortar or in the form of rigid acrylic membranes. For this reason, to ensure complete waterproofing, it should be planned taking into consideration the aggregates and other sealing strategies of a structure.
This care is important to avoid waterproofing failures on surfaces that are subject to cracks and fissures. So, it is recommended for baldrames and wall footings.
2. Flexible Waterproofing
The flexible type is aimed at surfaces that are subject to dilatations and vibrations. The waterproofing products used here present more elastic properties. Therefore, they can conform to the structure during movement and thus cover cracks and fissures. In other words, it is the most used option in the external areas of buildings, especially in regions that are very exposed to the sun.
It is excellent for internal areas and can be applied on slabs and balconies. For commercial and industrial use, it is very suitable for suspended reservoirs and tanks. Besides the most common use which is in swimming pools.
There are two main types of flexible waterproofing:
- the membranes, which are shaped on site by means of processes under heat or cold (emulsions);
- the blankets, prefabricated.
In addition, it is important to remember that to increase the efficiency of the waterproofing, several overlapping layers of different materials can be applied.
In recent years, a new type of waterproofing was developed: semi-flexible. For this reason, it has not yet been included in Brazilian technical standards. Therefore, it is necessary to be very careful when using it, describing it properly during the basic and executive projects.
Basically, it consists of a bicomponent material (polymeric mortar), a powder added to a liquid. When mixed, they form a mortar that is easy to apply.
Despite presenting intermediate characteristics between rigid and flexible, they are not indicated for surfaces subject to thermal expansion.
In addition, they present low mechanical resistance, which does not allow their use on surfaces subject to traction and friction, with people and equipment traffic.