  Aims: To derive observational properties and physical parameters of the
progenitor stars of type IIP supernovae SN 2005ay and SN 2005cs from their
U,B,V,R,I CCD photometry, and to define their velocity behaviour. Methods:
Light curves are analysed, and the velocities and spectral characteristics of
SN 2005cs are obtained using synthetic spectra modeling. Results: Both
supernovae are found to be fainter than the average
  SN IIP, with SN 2005cs being more subluminous and showing slight brightening
in the second half of plateau stage in the
  V,R,I bands and a low expansion velocity.
  The effects of two different plausible distance moduli on the derived
physical parameters of SN 2005ay are considered.
  Two approaches are used to recover the amounts of the ejected 56Ni,
indicating masses of the order of
  0.02 Msun, although late luminosities might indicate a higher amount for SN
2005ay, especially for the large distance case.
  Constraints on the progenitor properties are also presented, based on
empirical analytical models. Two approaches are used to estimate the expansion
velocities at the middle of the plateau phase. SN 2005cs represents an example
of where all 3 physical parameters, velocity, energy and 56Ni mass are lower
than average, a correlation not always observed in SNe IIP. SN 2005ay may
belong to the same class if the shorter distance possibility is adopted.
Furthermore, the estimated mass range for SN 2005cs is in agreement with limits
established by using pre-supernova imaging.
