With the deployment of an ever increasing number
of radio based services, such as 5G, a complete understanding
of the radio propagation phenomena inside buildings is expected
to be of utterly importance in the future, both for appropriate
indoor radio planning and assessment of human exposure to electromagnetic
radiation. Surprisingly, no regulations are currently
in force which cover the RF transparency of buildings. It may
well be justifiable on health and safety grounds (i.e. use of mobile
phones or TETRA radio in emergency situations). For instance,
there is substantial use of metal within current buildings which
causes major problems for radio propagation. On the other hand,
Building Information Modelling (BIM) is seen as a key technology
and methodology to improve productivity and integration across
various disciplines throughout the Architecture, Engineering
and Construction (AEC) value chain. Although many valuable
information has been added to such databases in the last
years, detailed information about the radio wave propagation
characteristics of buildings and building materials have been
absent. This paper presents a multilayer Electromagnetic (EM)
simulation tool to assess the radiofrequency transparency of
building wall structures, which allows to explore different layer
arrangements and determine the overall frequency response. In
particular, the assessment of EM properties of different types of
building walls commonly used in building construction, combined
into one complete EM tool, is proposed. This is sought to be
a valuable feature to be considered towards the integration
with BIM-based simulation methods to provide unprecedented
visualisation of the radio coverage within the building, allowing
for the optimisation to meet specific facility radio requirements.