Ventilated facades are a constructive solution widely used both in new construction and in the renovation of existing buildings. In order to comply with all the requirements expected by the final users and demanded by all building technical regulations, ventilated facades must be waterproof and have an optimal insulation.
The current ventilated facades have their origin in the second quarter of the 20th century in England, with the appearance of the "Cavity Wall", which is a two-sheet wall joined by means of staples and with a ventilated gap between them. The initial advantage of this type of facades was that it prevented the infiltration of rainwater.
A ventilated facade is a type of enclosure composed of external cladding, ventilated gap, insulation on the main sheet and interior finish. They must meet several requirements contained in different documents of the Technical Building Code:
- Energy saving (Compliance with DB-HE1).
- Protection against noise (Compliance with DB-HR).
- Fire safety (Compliance with DB-SI2).
- Absence of condensation (Compliance with DB-HE1).
- Protection against water (Compliance with DB-HS1).
Ventilated facades with projected polyurethane systems
In the specific case of ventilated facades where projected polyurethane is used as insulation, the composition of the whole system would be as follows:
Some of the advantages of ventilated facades using projected polyurethane as insulating material are:
- There are no thermal bridges.
- Optimization of space. By using projected polyurethane, we achieve maximum insulation with the minimum thickness of insulating material.
- Acoustic insulation. It improves the acoustic behavior of the building complex.
- It avoids condensation. It allows the building to transpire naturally, thus avoiding condensation.
- Long useful life. Projected polyurethane is a material that maintains its properties during the useful life of the building, guaranteeing its durability.
- And finally, the advantage we are analyzing in these lines: the impermeability of the facade against rainwater.
The importance of watertightness in ventilated facades
The closed cell projected polyurethane is a continuous intermediate coating that guarantees compliance with the water protection requirement on the Technical Code. It can be applied to any façade, with any degree of watertightness, and without any previous rendering. It meets a degree of watertightness of 5, the maximum. In addition, its continuity guarantees the non-existence of unwanted joints or cracks through which water can get into the building.
In ventilated facades, where thermal insulation is always exposed to the action of rainwater, it is essential that the insulation acts as a waterproof barrier. In this way, it will protect the main sheet of the facade from water and it will not affect the thermal performance of the insulation system.
Do not hesitate to contact us if you need further information on Synthesia Internacional's polyurethane systems.