  The interior of Enceladus, a medium sized icy moon of Saturn hosts
hydrothermal activity and exhibits tidal heating and related geyser-like
activity. There are major disagreements in the existing literature on the
porosity of the interior, due to the different theoretical assumptions on which
porosity related calculations were based. We present an application of
experimental equations - derived for Earth - for icy planetary objects and
Enceladus in particular. We chose a set of boundary values for our initial
parameters from measured porosity values of chondrite samples as references,
and calculated the porosity related values of Enceladus using various
approaches. We present a comprehensive investigation of the effects of using
these different porosity calculation methods on icy moons. With our most
realistic approach we also calculated the same values for Earth and Mars for
comparison. Our result for Enceladus is a minimum porosity of about 5\% at the
centre of the body. For the total pore volume we estimated $1.51*10^7 km^3$ for
Enceladus, $2.11*10^8 km^3$ for Earth and $1.62*10^8 km^3$ for Mars. Using the
same method, we estimated the total pore surface area. From this we derived
that the pore surface under a given $1 km^2$ area of the surface on Enceladus
is about $1.37*10^9 km^2$, while for Earth this value is only $5.07*10^7 km^2$.
