Recently, two researchers from School of Building Engineering
at UPM have developed a ventilated façade with a double chamber and flow
control device that significantly saves energy in buildings. This sustainable
and efficient solution can be applied in both rehabilitation works and new
buildings due to its simplicity of implementation.
The facade is the main
constructive element of a building that allows us to meet the requirements of
energy efficiency and interior comfort established in the national and
international rules and directives of the construction sector. The type of system,
the design and the right execution of the façade itself are critical aspects
that determine the final energy consumption of the building.
Today, the air flow
expenses are of 40% -- 65% of the total expenses of a building. Buildings in a
Mediterranean-continental climate like in Spain suffer in winter energy losses
through their north and east facades due to low temperatures. Likewise, these
buildings in summer obtain energy gains through their south and west facades
due to solar radiation. In both cases, the air flow is needed in the building
in order to maintain suitable inner conditions for their inhabitants,
counteracting the energy gains-losses trough the building envelope.
In order to improve the
energy efficiency of facades, two researchers from the group of Tecnología
Edificatoria y Medio Ambiente (TEMA) at UPM have developed a new system of
ventilated façade. Today, the conventional ventilated facades are composed of
an inner sheet, thermal insulation, ventilation chamber and exterior finish.
The new facade designed
adds a second air chamber between the existing one and the facade insulation,
both chambers are interconnected by the bottom of the façade. Another feature
is a new element at the top to regulate the air flow in the chambers, depending
on the gradient of the existing temperature between inside and outside the
building.
Ventilated façade with a
double chamber presents two improvements over the conventional system. Firstly,
energy gains-losses are reduced through the facades reducing, consequently, the
energy consumption due to air flow. Secondly, the design of the system helps to
reduce the vertical temperature gradient along the envelope, homogenizing the
air temperature in the chambers throughout the year.
By minimizing the vertical
thermal gradients, global consumption due to energy gains-losses through the
façade depends less on the height of the building, preventing the upper houses
to present higher or lower indoor comfort and degree of energy efficiency than
the lower houses. Besides, this system is a sustainable and efficient solution
that can be applied in both rehabilitation works and new buildings due to its
simplicity of implementation.
The initial over cost can
be short-term amortized if we consider the remarkable energy savings of this
design.
The authors of this work
say, "this research work highlights the potential energy efficiency of
buildings through the redesign of conventional construction systems."
This work has been
recently published in the Energy
and Buildingsjournal and also been patented.
Source: ScienceDaily-10th November,2017
