Comparison of high-performance and conventional internal insulation materials based on hygrothermal analysis using in situ measurements and simulation

Following the European directive to reduce CO2 emissions of
existing buildings by improving energy efficiency, internal
insulation
systems play a central role in the renovation of historically
valuable buildings which cannot be insulated from the
outside for reasons of monumental protection, or in cases
where no additional exterior space is available. However, besides
the thermal property of insulation systems, there are
other relevant properties to be considered before choosing an
internal insulation system, such as the hygrothermal behavior
which plays a particularly important role in diffusion-open interior
insulation systems. As the internal insulation layer reduces
the temperature of the existing wall during the heating season,
its drying potential after rain events is considerably reduced.
In addition to the effects of moisture from the outside (mainly
wind driven rain), the entry of humidity from the inside through
diffusion plays an important role. In the presented study, high
performance insulation materials with nanostructure based on
silicon dioxide and polyurethane are compared to conventional
material based on wood fiber from a hygrothermal point of view
by analyzing in situ measurements and simulations.