Characteristics of polyurethane waterproofing

Polyurethane is the material resulting from the chemical reaction of two elements, polyol and isocyanate, obtained by projection or injection. Versatile, resistant, durable, easy to install and with a very low environmental impact, it is widely used in construction and industry as thermo-acoustic insulation and also as a waterproofing agent.


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Effective waterproofing with polyurethane


Waterproofing of roofs, ceilings, floors, walls and ceilings is essential to prevent the weakening of the building structure. This not only prevents water leaks but also eliminates the risk of condensation. In this way, the appearance of fungus and mould is prevented, as well as damage to floors and even the interior of buildings, which can be affected by ineffective or damaged waterproofing. Therefore, waterproofing properly saves on expensive repairs, as well as extending the life of the buildings.


Among the waterproofing systems that exist, one very effective is liquid polyurethane applied in situ. It forms a homogeneous membrane, without joints, with great adhesion, impenetrable, resistant, easy to install and elastic, although very hard. It is indicated for passable roofs, terraces, balconies, sloping roofs and rooftops, allowing intense traffic and supporting demanding weather conditions. It adapts to all types of morphologies and even adheres to porous substrates such as concrete. It allows the protection of gutters and eaves, completely sealing the existing gaps and joints. It also gives excellent results in tunnels, reservoirs or metal installations.


Urespray P-500 for waterproofing


The Synthesia Technology Urespray range


In addition, the application of an elastomeric system based on pure polyurea, which is obtained from the reaction of polyetheramines and isocyanate, provides a total water tightness together with great resistance. This is the case of the Synthesia products in the Urespray range. They are waterproofing products made of hybrid and pure polyurea that are applied by projection, covering the surface homogeneously, adapting to even the most unusual shapes. They can also be applied vertically, in the case of Urespray F-100 (Hybrid Polyurea) and Urespray P-500 (Pure Polyurea), thanks to their rapid curing.

Before the installation, it is necessary to prepare the surface correctly, as well as to use the most suitable primer in each case, as described in the technical sheet. These products, besides having waterproofing properties, also have excellent mechanical properties such as resistance to abrasion, traction and tearing. They also present very good behaviour at low temperatures, as well as a great chemical resistance to a wide range of chemical agents.


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On the other hand, the P-500 Urespray system, pure polyurea, is classified as W3, system lifetime (EOTA) of 25 years, according to ETE (16/0153). It also has a good reaction to fire properties, being classified as Class E and Broof (t1) according to EN 13501-1 and EN 13501-5, respectively. On the other hand, the Urespray P-500 system is suitable for applications in contact with drinking water and food.

Due to its fast curing time, it can be walked on within a few hours of application, although the optimum is to wait 24 hours.

In summary, investing in polyurethane waterproofing is the best option to keep buildings healthy and safe.


Urespray P-500 for waterproofing





Fire response of polyurethane: false myths

Polyurethane systems surround our daily lives, however, we still hear some voices that call into question the response of polyurethane in case of fire. 

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Technical Data Sheet Poliuretan Spray S-35RGB/ECO