In general it can be concluded that vegetation can really contribute
to the sound insulation of the building, in the design of
VGS all the factors that influence their acoustic behaviour must
be considered. Concerning this, studies regarding to the types of
plants, the thickness of the vegetation layer, the thickness and
composition of the substrate layer, the type of support structure
and materials to be used, as well as to take measures to prevent
transmission of sound on the early design phase (structural impenetrability
and insulation) should be made.
In addition, future experiments should be made following international
standards of measurement in order to compare experiments
and results relating to the different VGS.